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Transcript
UC Berkeley Electrical Safety Program
UC Berkeley - Electrical Safety Program
Go to the Table of Contents
Click here to learn how this program applies to you.
Lead: Jim Gilson, PE., Campus Safety Engineer
Phone: (510) 643-9575
E-mail: [email protected]
Team: Health & Safety
Associate Director: Brandon DeFrancisci
Description:
More than 3,600 disabling electrical contact injuries occur in the workplace
and more than 2,000 workers are sent to burn centers with electric burns every year in the U.S.
Every day one person dies from electrical incidents.
This program provides information about electrical hazards, guides University safe-work policy,
electrical safety procedures, equipment design, development and installation for all electrical
work, equipment and systems at UC Berkeley (UCB). All faculty, staff, students, visitors and
contractors must comply with the requirements of this program as it ensures their safety by:
•
Defining safe work practices and use requirements for all people who work with
electrically energized equipment as part of their normal job / research duties.
•
Establishing training requirements for “qualifying” and “authorizing” persons who
work on or near energized electrical circuits and components, and establishing
“qualification” requirements for UCB-hired electrical contractors.
•
Establishing a process for evaluating the hazards of every potentially energized
electrical work task and for determining appropriate hazard controls.
•
Establishing a formal process for controlling energized electrical work through an
assessment and documented “energized work” or “Hot Work Permit” approval
process.
•
Chartering a “Campus Electrical Safety Committee” to oversee and guide
electrically safe equipment procurement, work practices and procedures at UCB.
The UC Berkeley Electrical Safety Program must be applied to every individual piece of
equipment, research / experimental apparatus or facility that has electrical energy as a source
of power and/or utility distribution in compliance with Cal/OSHA code, California Electrical Code,
California Building / Construction Code and NFPA Life Safety Code.
For basic information about Electricity and Electrical Safety, please review the “Frequently
Asked Questions / Fact Sheet” to become familiar with electrical hazards and controls.
Page 1 of 96
UC Berkeley Electrical Safety Program
How does this program apply to you and/or your
Department?
If you conduct, supervise or contract-hire:
Office Work
If you or your department conducts office work, then only the “Extension Cord Use” portion of
this program applies to the office work done by you or your department. In addition, you must
know the basic requirements of all Faculty, Staff and Students for compliance with this program.
Research / Experimental Design and Development
If you or your department conducts experimental design, equipment development, or connection
to facility electrical distribution systems or other equipment that generates or in some way uses
or stores electricity, whether AC or DC, then some portions of this program impact your work
including the University safe-work policy, safe work rules, safe design practices, space
requirements, requirements for hiring electrical contractors and experimental procedures to be
followed when working with or nearby electricity. Click on the following links to learn your
responsibilities, safe-work procedures, training available/requirements and recordkeeping
requirements. Also, go to Attachments K through V for specific guidance on equipment design,
installation and the electrical contractor procurement process.
Electrical Workers
If you work with electricity, or on equipment that uses electricity as a source of energy for
operation, or equipment that generates electrical current, then portions of this program dictate
how you must be “Qualified” and “Authorized" to conduct electrical work according to the
University safe-work policy, safe work rules, training requirements / frequency, and use of tools
and personal protective equipment, etc. that are to be followed during the course of your work at
UCB.
Electrical Equipment / Services Procurement
If you or your department procures electrical equipment or contractor services, then this
program dictates the process to be followed to assure only electrically safe equipment and
qualified contractors are brought onto UCB property, and that the installation of equipment, or a
contractor’s work, does not adversely impact the UCB electrical system or safety of the UCB
community.
Page 2 of 96
UC Berkeley Electrical Safety Program
Electrical Contractors
If you or your department hire contractors to do electrical work either on facilities and/or
equipment owned / controlled by you or your department, then sections of this program dictate
the necessary qualifications of the contractor(s), and process to be followed for procuring their
services, as well as safe work practices to be followed for working and interfacing with the UCB
electrical system, etc…
Electrical Safety Committee
If you are an Electrical Worker or a researcher who develops / works with electricity, you are
encouraged to participate in the campus Electrical Safety Committee as chartered by this
program.
Energized / Hot Work
This program requires that all electrical energy be isolated, locked and tagged out according to
the UCB Energy Isolation LOTO Program prior to working on any equipment with potentially
energized electrical conductors. If you or your department conducts work on energized
electrical circuits or components, then you and your department must first meet certain criteria
that demonstrate documented specific need to “work hot”, assure there are “qualified” and
“authorized” personnel / contractors who may conduct the “hot work”, and then you and your
department must follow the “Hot Work Permit” requirements of this program as outlined in
Appendix 1.
Facility Design / Construction
If you or your department oversee the design / development / construction of new or refurbished
facilities, then sections of this program impact the design/work practices and the arc-flash study
specification to be included as part of your RFP / Bid process.
Page 3 of 96
UC Berkeley Electrical Safety Program
For guidance about your roles / responsibilities and needed
training, click on the links below:
All Faculty, Staff and Students
“Qualified and Authorized Person"
Supervisors (Includes PIs, Researchers, Staff and/or Project Managers)
Anyone who procures Electrical Contractor Services
Associate Vice Chancellor of Facility Services:
PPCS Electrical Engineer
Electrical Safety Committee (ElSC)
Director Environment, Health and Safety (EH&S)
EH&S Safety Engineer
Page 4 of 96
UC Berkeley Electrical Safety Program
UCB Electrical Safety Program - Table of Contents
[Control-Click on any Heading or Subheading in the
Table of Contents to go to that section of the program. All are hyperlinks.]
UC Berkeley - Electrical Safety Program ..................................................................... 1
Description: .................................................................................................................... 1
How does this program apply to you and/or your Department? ............................... 2
Office Work .................................................................................................................... 2
Research / Experimental Design and Development ........................................................ 2
Electrical Workers .......................................................................................................... 2
Electrical Equipment / Services Procurement ................................................................. 2
Electrical Contractors ..................................................................................................... 3
Electrical Safety Committee............................................................................................ 3
Energized / Hot Work ..................................................................................................... 3
Facility Design / Construction ......................................................................................... 3
For guidance about your roles / responsibilities and needed training: ................... 4
All Faculty, Staff and Students ............................................................................ 4
“Qualified and Authorized Person" ...................................................................... 4
Supervisors (Includes PIs, Researchers, Staff and/or Project Managers) ........... 4
Anyone who procures Electrical Contractor Services .......................................... 4
Associate Vice Chancellor of Facility Services: ................................................... 4
PPCS Electrical Engineer ................................................................................... 4
Electrical Safety Committee (ElSC) ..................................................................... 4
Director Environment, Health and Safety (EH&S) ............................................... 4
UCB Electrical Safety Program - Table of Contents ................................................... 5
1. Purpose & Introduction .......................................................................................... 13
2. Applicability & Scope .............................................................................................. 13
3. Roles & Responsibilities ....................................................................................... 14
All Faculty, Staff and Students must:..................................................................14
Page 5 of 96
UC Berkeley Electrical Safety Program
Supervisors (Includes PIs, Researchers, Staff and / or Project Managers)…. ....14
Researchers, PIs, and Staff who work in research designing, developing and
installing electrical equipment must: ...................................................................15
Researchers, PIs, and Staff that procure Electrical Contractor Services must: ...15
Associate Vice Chancellor of Facility Services ...................................................16
PPCS / Campus Electrical Engineer ..................................................................16
Electrical Safety Committee ...............................................................................16
Director - Environment, Health and Safety (EH&S) ............................................17
EH&S Safety Engineer .......................................................................................17
4. Definitions ............................................................................................................... 19
Accessible (equipment) ......................................................................................19
Accessible (readily) …………………………………………………………………..19
Acronyms………………………………………………………………………………19
Approved……………………………………………………………………………….19
Arc Blast………………………………………………………………………………..19
Authority Having Jurisdiction (AHJ) ....................................................................20
Authorized Person…………………………………………………………………….20
Conductive……………………………………………………………………………..20
Contractor………………………………………………………………………………20
De-energized…………………………………………………………………………...20
Electrical Hazard……………………………………………………………………….20
Electrical Safety………………………………………………………………………..20
Electrically Safe Work Condition (see also “verified de-energized”) ...................20
Enclosed (equipment / conductors) ....................................................................20
Energized (see also “Live Parts” or “Hot Work”) .................................................20
Exposed (as applied to live parts) ......................................................................20
Flame-Resistant (FR) …………………………………………………………………21
Flash Hazard…………………………………………………………………………...21
Grounded……………………………………………………………………………….21
Guarded………………………………………………………………………………...21
Hot Work………………………………………………………………………………..21
Page 6 of 96
UC Berkeley Electrical Safety Program
Insulated………………………………………………………………………………..21
Isolated Equipment……………………………………………………………………21
Labeled…………………………………………………………………………………21
Limited Approach Boundary ...............................................................................21
Listed……………………………………………………………………………………22
Listing Organization……………………………………………………………………22
Live Parts (see also energized) ..........................................................................22
Nationally Recognized Testing Laboratory .........................................................22
Overload ……………………………………………………………………………….22
Qualified Person……………………………………………………………………….22
Supervisor………………………………………………………………………………22
Shock Hazard………………………………………………………………………….22
Verified De-energized (see also “electrically safe work condition”) .....................22
Voltage (of a circuit) …………………………………………………………………..23
Voltage to Ground……………………………………………………………………..23
Working Near (energized / live parts) .................................................................23
Working On (energized / live parts) ....................................................................23
5. Electrical Hazards and Controls ........................................................................... 24
5a. Electrical Hazards associated with work around electricity: .....................................24
Arc Flash……………………………………………………………………………….24
Arc Blast………………………………………………………………………………..24
Burns……………………………………………………………………………………24
Delayed Effects………………………………………………………………………..24
Electrical Shock Hazards ...................................................................................24
5b. Hierarchy of Electrical Hazard Controls ...................................................................25
5b1. Energy Isolation / Lockout Tagout Program (EI/LOTO) ..............................25
5b2. Engineering Controls..................................................................................25
5b3. Personal Protective Equipment (PPE) ........................................................26
5b4. Administrative Controls ..............................................................................26
6. Electrical Safe Work Policy and Procedures ........................................................ 27
UCB’s Electrical Safe Work Policy .................................................................................27
Page 7 of 96
UC Berkeley Electrical Safety Program
6a. Electrical Safe Work – Administrative Procedures ............................................ 28
“Qualifying” and “Authorizing” Personnel .......................................................................28
General Guidelines for “Qualifying” Personnel ...............................................................29
Specific “Qualifying Criteria” ..........................................................................................29
General Guidelines for “Authorizing” Personnel .............................................................30
Specific Authorizing Personnel Criteria ..........................................................................30
Electrical Safety Committee (ElSC) ...............................................................................31
Procurement of Contract Services for Electrical Work ...................................................31
Developing Purchase Requisition documentation: .........................................................32
Electrical Distribution Systems (Premises Wiring / Facility Wiring) .................................32
Who does the work: …………………………………………………………………..32
Who approves “Hot Work”: .................................................................................32
Who approves Isolation or Shut-down work: ......................................................33
Who approves contractor work:..........................................................................33
Capital Projects – Hot Work Exception:..............................................................33
Electrical Equipment Work.............................................................................................33
Who does the work: …………………………………………………………………..33
Who approves “Hot Work”: .................................................................................34
Who approves Isolation or Shut-down work: ......................................................34
Who approves contractor work:..........................................................................34
Electrical Research Equipment Design and Installation: ................................................34
6b. Electrical Safe Work – Job-site Procedures: ...................................................... 36
General Safe Work Rules ..............................................................................................36
Energized “Hot Work” Electrical Work Requirements .....................................................37
7. Training Requirements .......................................................................................... 37
All Faculty, Staff and Students ...........................................................................37
Trades Persons and others doing Electrical Work ..............................................38
Supervisors (includes PIs, Researchers, Staff and / or Project Managers) .........38
Researchers, PIs, and Staff that hire Electrical Contractor Services ..................38
Researchers, PIs, and Staff who work in research designing, developing and
installing electrical equipment ............................................................................39
Page 8 of 96
UC Berkeley Electrical Safety Program
Associate Vice Chancellor of Facility Services and the EH&S Director ..............39
PPCS / Campus Electrical Engineer ..................................................................39
EH&S / Campus Safety Engineer .......................................................................40
Electrical Safety Committee (ElSC) ....................................................................40
8. Record Keeping Requirements ............................................................................. 40
Hot Work Permits, Shut Down Requests, Switch Logging, .................................40
Supporting documentation, Purchase Orders, RFPs, .........................................40
Approvals for Energized Electrical “Hot Work” ...................................................40
Training records, Tail-Gates and Work-site Orientations ....................................40
Qualification Determination Records ..................................................................41
Authorization Records ........................................................................................41
9. References ............................................................................................................... 41
Issued By and Next Review Date .......................................................................41
10. Appendix and Attachments .................................................................................. 42
Appendix 1 – Hot Work Permit Procedure ................................................................ 43
Introduction: …………………………………………………………………………..43
UCB Electrical “Hot Work Policy”: ......................................................................43
Who May Conduct Electrical “Hot Work”: ...........................................................43
Exemption of “Who May Conduct Hot Work”: .....................................................43
Energized Electrical Work “Hot Work” Procedure – 9 Steps .................................. 43
Attachment A – Hot Work Flow Chart / Checklist ...............................................45
General Electrical Safe Work – Jobsite Procedures ...........................................46
Back to Hot Work Procedure ................................................................................46
Electrical Two-Person Rules ..............................................................................47
Electrical Safety Watch Rules ............................................................................48
Attachment B: Electrical Hazard Classification and Requirements ....................49
Attachment C: Qualification Training Requirements ..........................................50
Attachment D1: Project Documentation Requirements .....................................51
Attachment D2: Personnel Hot Work Qualification – Annual Record ..................52
Attachment E: Shock Protection Boundaries ......................................................53
Attachment F: Flash Protection Boundary .........................................................54
Page 9 of 96
UC Berkeley Electrical Safety Program
Attachment G: Protective Clothing Characteristics ............................................55
Attachment H: Shut Down Request Form..........................................................56
Attachment I: Electrical Hot Work Permit ...........................................................58
Attachment J: Switching Log Form ....................................................................59
Definitions: …………………………………………………………………………….60
Attachment K: Electrical Equipment Safe Work Space Requirements ................................61
Attachment L: Research Equipment Fabrication and Maintenance ...................................62
Designs………………………………………………………………………………….62
Equipment Acceptability ......................................................................................62
Equipment Safety Practices .................................................................................63
Enclosures………………………………………………………………………………63
Cord and Plug Equipment (Testing and Maintenance) .......................................64
Attachment M: Practices for Heating Tapes and Cords .....................................................65
Attachment N: Practices for Flexible Cords ......................................................................67
Attachment O: Use of Extension Cords ........................................................................69
Acceptable Combination (for Office Only) ..............................................................70
Relocatable Power Strips / Power Taps (for Office and Lab Bench Tops Only) .........70
Attachment P: Practices for Portable Workbenches ..........................................................71
Attachment Q: Practices for Power Supplies ....................................................................72
Primary Disconnect…………………………………………………………………….72
Overload Protection…………………………………………………………………….72
Floating Power Supplies .......................................................................................72
Attachment R: Practices for Capacitor Hazards ................................................................73
Low voltage (<600v) capacitor safety practices: ....................................................73
High voltage (>600v) capacitor safety practices: ...................................................73
Storing capacitors - safety practices: ....................................................................73
Attachment S: Practices for Inductor and Magnet Hazards ...............................................74
Safety Practices:………………………………………………………………………..74
Attachment T: Practices for Control and Instrumentation Design ......................................75
Attachment U: Practices for Ground Fault Circuit Interrupters (GFCIs) ...............................76
Attachment V: Nationally Recognized Testing Laboratories (NRTL’s) .................................77
Page 10 of 96
UC Berkeley Electrical Safety Program
Attachment W: Electrical Safe Work Specifications ..........................................................78
Attachment X: Arc Flash, Arc Fault, Ground Fault Calculation Specifications ......................79
ATTACHMENT Y – EH&S FAQ / FACT SHEET .......................................................... 84
Table of Contents ........................................................................................................ 84
Why should you be concerned about electrical hazards? ..............................................85
Electricity: The Basics ................................................................................................ 86
What affects the flow of electricity? ................................................................................86
How does water affect the flow of electricity? ................................................................86
What causes shocks?....................................................................................................86
What effect do shocks have on the body? .....................................................................87
Effects of Electric Current in the Human Body ........................................................ 87
What kind of burns and other injuries can a shock cause? ............................................88
Why do people sometimes “freeze" when they are shocked? ........................................88
What should you do if someone" freezes" to a live electrical contact? ...........................89
How can you tell if a shock is serious? ..........................................................................89
What is the danger of static electricity?..........................................................................89
Protection Against Electrical Hazards....................................................................... 90
What is the best way to protect yourself against electrical hazards? ..............................90
What protection does insulation provide? ......................................................................90
How do you identify different types of insulation? ..........................................................90
What is guarding and what protection does it offer? ......................................................91
What is grounding and what proection does it offer? .....................................................91
Basic Facility Wiring - 101 .............................................................................................92
What are circuit protection devices and how do they work? ...........................................92
What work practices help protect you against electrical hazards? .................................93
How can you protect yourself against metal parts that become energized? ...................93
How can you prevent an accidental or unexpected equipment startup?.........................94
How can you protect yourself from overhead power lines? ............................................94
What protection does personal equipment offer? ...........................................................95
What role do tools play in electrical safety? ...................................................................95
What special training do qualified and authorized personnel need?...............................95
Page 11 of 96
UC Berkeley Electrical Safety Program
How do safety and health programs control electrical hazards? ....................................96
Page 12 of 96
UC Berkeley Electrical Safety Program
Electrical Safety Program
1. Purpose & Introduction
More than 3,600 disabling electrical contact injuries occur in the workplace and more than 2,000
workers are sent to burn centers with electric burns every year in the U.S. Every day one person dies
from electrical incidents.
This program guides safe-work policy and procedures for all electrical work at UC Berkeley (UCB). All
faculty, staff, students, visitors and contractors must comply with the requirements of this program as it
ensures their safety by:
 Defining safe work practices and use requirements for all people who work with electrically
energized equipment as part of their normal job duties.
 Establishing training requirements for qualifying and authorizing UCB employees who work on
or near energized electrical circuits and components.
 Establishing a process for evaluating the hazards of every potentially energized electrical work
task and for determining appropriate hazard controls.
 Establishing a formal process for controlling energized electrical work through an assessment
and documented “energized work” approval process.
 Establishing a formal process for ensuring safe electrical work through a safe electrical
equipment and contract services procurement approval process.
Go to Table of Contents
2. Applicability & Scope
This program applies to any electrical work at UC Berkeley when someone:
 Conducts testing or repairing of electrical or electronic equipment.
 Works on or adjacent to electrical distribution and hard-wired electrical equipment.
 Designs, builds, or modifies electrical or electronic equipment.
 Procures by UCB purchase requisition or contract some type of electrical / electronic contract
work or equipment.
 Supervises personnel or contractors who perform electrical / electronic work.
This Electrical Safe Work Program provides the minimum knowledge of safe-work practices necessary
to guide the work noted above and prevent electrical shock, burns or property loss. Reading this
program does not qualify the reader to perform electrical work. Safe-work practices beyond the
scope of this program must be established for each work area by responsible persons and at minimum
must include the safety concerns, policies and procedures outlined by this program.
Page 13 of 96
UC Berkeley Electrical Safety Program
Go to Table of Contents
3. Roles & Responsibilities
Everyone is responsible for their own safety and that of their coworkers through knowledge and
application of safe-work practices, procedures and use of safe-work equipment at a level appropriate to
the hazards encountered in their workplace. Toward that end, the following personnel must
demonstrate and act according to their level of responsibilities:
All Faculty, Staff and Students must:









Stop immediately any activity believed to be hazardous. Everyone at UCB has this authority and
obligation to speak up and stop unsafe work.
Perform electrical work only when the electrical hazards are identified, adequately controlled,
and when they are properly trained to perform safe-work tasks.
Attend required training to achieve understanding of how to work safely and to respond to
abnormal or emergency situations.
Do no work requiring specialized training if they are not current in their required training without
appropriate prior approval from their manager, supervisor, PI, etc.
Notify their manager, supervisor, PI, etc. of any condition or behavior that poses a potential
hazard.
Wear and use appropriate personal protective equipment (PPE).
Immediately report any occupational injury or illness from an electrical shock to their manager,
supervisor, PI, etc. regardless of how minor the shock is perceived to be.
Assure that you have been trained per the requirements of this program by reading and
understanding these responsibilities.
Only use electrical extension cords according to the guidelines of Attachment O.
Go to Table of Contents
Go back to “How this program applies to you”.
Supervisors (Includes PIs, Researchers, Staff and / or Project Managers)….
Of electrical workers and persons potentially exposed to energized conductors must:





Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
Establish, implement, and maintain procedures and/or work practices that ensure safe electrical
work by their subordinates as outlined in the Safe-Work Procedures section of this program at
minimum.
Maintain a safe work environment for all locations under their jurisdiction.
Take corrective action to control any potentially hazardous operation or condition.
Ensure that approved, maintained, and tested personal protective equipment and clothing is
provided, available, and used properly by their subordinates.
Page 14 of 96
UC Berkeley Electrical Safety Program





Assign only “Qualified and Authorized” personnel to perform electrical work.
Ensure that employees understand how to work safely by personally conducting a pre-job
briefing as necessary.
Ensure that work-routines, inspections, or surveillances conducted within the Limited,
Restricted, or Prohibited approach boundaries are conducted by personnel qualified to work
within those spaces.
Ensure that all injuries are treated promptly and reported to Workers Compensation and EH&S
within 8 hours of occurrence.
Assure that you have been trained per the requirements of this program.
Go to Table of Contents
Go back to “How this program applies to you”.
Researchers, PIs, and Staff who work in research designing, developing and
installing electrical equipment must:





Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
Follow all roles / responsibilities of the “Supervisor” as noted above.
Integrate safe electrical design practices and safe work procedures into research design,
equipment selection and apparatus development through familiarity and application of the
guidance of the Attachment documents.
Implement “Hot Work Permit” procedures whenever hot work is done in their lab under their
direction.
Assure that you are familiar with and have been trained per the requirements of this program.
Go to Table of Contents
Researchers, PIs, and Staff that procure Electrical Contractor Services must:






Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
Develop documentation of the electrical hazards involved in the planned work by completing
Attachment B.
Identify the required qualifications of the contractor performing the work as part of the “purchase
requisition” documents using Attachment C.
Obtain approval of proposed work equivalencies that are outside work-practices and equipment
approved in this program and its attachments in writing from the EH&S Safety Engineer and the
PPCS Electrical Engineer.
Request work requiring shut-down of electrical circuits in any facility using a PP-CS “Shut Down
Request Form” that is approved by the campus Electrical Engineer prior to shut-down taking
place using Attachment I.
Assure that you have been trained per the requirements of this program.
Go to Table of Contents
Page 15 of 96
UC Berkeley Electrical Safety Program
Associate Vice Chancellor of Facility Services



Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
Interprets the California Electrical Code as it applies to existing and new UCB facilities. The
AVC may delegate this authority to the PP-CS Electrical Engineer, consulting project engineers,
or other qualified professionals as need may dictate.
Delegates a qualified Management Representative to charter and Chair the Electrical Safety
(NFPA70e) Committee (ElSC).
Go to Table of Contents
PPCS / Campus Electrical Engineer
The Campus Electrical Engineer is the authorized representative of the PP-CS AVC and has the
responsibility to ensure the acceptability of facility / infrastructure electrical wiring and apparatus. The
PP-CS Electrical Engineer must:
 Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
 Provide technical support for the UCB electrical safe work program.
 Be a permanent member of the UCB Electrical Safety Committee.
 Ensure the designs of electrical equipment installations (facilities) are compliant with the
requirements of this program.
 Provide testing and evaluation, as needed, for research or unique non-NRTL equipment, and
determine impact on any campus facility.
 Have access to and oversee facility electrical safe-work inspection services for all UCB
workplaces including construction and leased operations.
 Provide hazard assessment for electrical work activities as requested by organizations
performing electrical work.
 Ensure manufacturing, installation, testing and maintenance of electrical equipment is compliant
with appropriate regulations and standards.
 Work with Capital Projects to maintain and update the Specifications and other sections of this
program that impact building design / construction.
 Maintain and review Arc Flash Hazard one-line drawings and safe-work information database.
 Provide electrical safe-work guidance as needed to any work crew(s) on UCB property.
Go to Table of Contents
Electrical Safety Committee
All Electrical Safety Committee (ElSC) members have the responsibility to implement the UCB
Electrical Safe Work Program in the UCB built environment. The ElSC must:
 Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
Page 16 of 96
UC Berkeley Electrical Safety Program
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
Provide EH&S Safety Engineer with recommendations and requirements for training on
Electrical Safety.
Provide EH&S Safety Engineer with recommendations for funding of electrical safety initiatives.
Develop and review technical material related to the Electrical Safe Work Program and
application of the Energy Isolation – Lock out / Tag out Program to electrical hazards.
Maintain and update this program’s content and the technical electrical information in the
Energy Isolation - Lock Out/Tag Out Program.
Assist Supervisors and Project Managers who are hiring contractors in the interpretation and
application of this Electrical Safe Work Program.
Assist in training and safety awareness for electrical hazards at UCB.
Assess the performance of the Electrical Safe Work Program, including audits, inspections, and
reviews of electrical accidents, near misses and equipment procurement specifications.
Conduct periodic safety-reviews of electrical and electronic equipment and their installations,
compared to this program’s requirements, to assess its application at UCB and determine
opportunities for program improvement and application.
Go to Table of Contents
Director - Environment, Health and Safety (EH&S) is responsible for establishing and
maintaining the Electrical Safe Work Program, providing affected persons with information and training
on its content, and monitoring compliance by persons performing electrical work and their supervisors.
In addition, the Director must be familiar with the responsibilities of All Faculty, Staff and Students in the
application of the Electrical Safety Program in their own work.
Go to Table of Contents
EH&S Safety Engineer
The Campus Safety Engineer is the authorized representative of the Director - EH&S and has the
responsibility to ensure the acceptability of non-facility (experimental) electrical wiring and apparatus.
The Safety Engineer must:
 Be familiar with the responsibilities of All Faculty, Staff and Students in the application of the
Electrical Safety Program in their work.
 Conduct periodic assessments of electrical safe work program compliance at UCB and provide
feedback, incident reports and recommendations to the Electrical Safety Committee.
 Maintain documentation of electrical safe work policies and procedures for all UCB operations.
 Provide technical support for the UCB electrical safe work program
 Be a permanent member of the UCB Electrical Safety Committee.
 Evaluate existing workplace safety by inspecting, or directing the inspection of, the workplace
for California Electrical Code (CEC) and CalOSHA compliance.
 Have access to, and provide non-facility safe-work electrical inspection services for, all UCB
workplaces including research and leased operations.
 Provide assistance to academic departments by evaluation, or directing the evaluation, of the
acceptability of experimental electrical wiring and apparatus.
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Ensure electrical safety training course content complies with this Program, and ensures
qualified trainers are available as needed.
Develop and revise electrical safety training as necessary.
Review drawings, tests, and other documentation provided by project engineers, principal
investigators (PIs), or other responsible persons for compliance with accepted safety criteria
and code intent.
Consult with the appropriate specialists to verify that engineering, design, and construction
requirements have been correctly applied.
Conduct other inspections and analyses as necessary to verify the compliance and acceptability
of the apparatus involved.
Serve as the first contact Authority Having Jurisdiction (AHJ), providing professional
interpretations of CalOSHA electrical safety requirements, and as liaison with Regulatory
Agencies regarding Electrical Safe Work within UCB.
Assist the PPCS Electrical Engineer for interpretation and application of the NFPA 70, “The
National Electrical Code”, etc.
Work with Capital Projects to maintain and update the sections of this program that impact
building design / construction.
Provide administrative and technical support as necessary and may be requested by the
Electrical Safety Committee Chair to ensure the effective operation of this Committee.
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4. Definitions
Accessible (equipment) - Admitting close approach; not guarded by locked doors, elevation, or
other effective isolation means.
Accessible (readily) - Location or equipment capable of being reached quickly for actuation or
inspection without requiring personnel to climb over or remove obstacles or to resort to portable
ladders, etc.
Acronyms used in this program are:
AHJ: Authority Having Jurisdiction
ANSI: American National Standards Institute
AWG: American Wire Gauge
CalOSHA: California Occupational Safety and Health Administration
CEC: California Electrical Code (2007)
EH&S: Environment, Health & Safety
EI/LOTO: Energy Isolation - Lockout/Tagout
ElSC: Electrical Safety Committee
ETL – Inertek Testing Services (formerly ETL Testing Laboratories)
FM: Factory Mutual
J: Joules (watt-seconds)
JHA: Job Hazard Analysis
mA: Milliamperes
NEC: National Electrical Code also known as NFPA 70.
NESC: National Electrical Safety Code
NFPA: National Fire Protection Association
NFPA 70: National Electrical Code also known as the NEC.
NFPA 70E: Standard For Electrical Safety in the Workplace
NRTL: Nationally Recognized Testing Laboratory (e.g. UL = Underwriter’s Laboratory)
PPE: Personal Protective Equipment
SRC: Safety Review Committee
UCB: University of California Berkeley
UL – Underwriters Laboratories
V: Volts
W: Watts
Approved - Acceptable to the “Authority Having Jurisdiction” (AHJ).
Arc Blast - An explosive release of molten material and shock-wave from equipment caused by
high-amperage arcs / plasma.
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Authority Having Jurisdiction (AHJ) - A term used to define roles or responsibilities within this
program for various regulatory agencies, NRTLs, campus departments and UCB personnel who are
referenced or given authority by this program document and/or its application.
Authorized Person - A qualified person delegated by their supervisor to perform specific duties
under work hazard conditions known to that supervisor.
Conductive - Able to carry electric current.
Contractor - A general term used to define any outside individual, employer, business, or agency that
is hired by UCB to conduct any type of electrical work on UCB facilities or equipment, or who conducts
ancillary electrical work as part of fulfillment of a contract for any UCB Department or operation.
De-energized - Free from any electrical connection to a source of potential difference and from
electrical charge. This condition is otherwise known as “not having an electrical potential different from
that of the earth or ground”.
Electrical Hazard - A dangerous condition such that contact or equipment failure can result in
electric shock, arc flash burn, thermal burn, or arc blast injury.
Electrical Safety - Recognizing hazards associated with the use of electrical energy and taking
precautions so those hazards do not cause property loss, injury or death.
Electrically Safe Work Condition (see also “verified de-energized”) - A state in which the
conductor or circuit part to be worked on or near has been disconnected from energized parts,
locked/tagged in accordance with the Energy Isolation /LOTO Program, tested to ensure the absence
of voltage, and grounded if determined necessary.
Enclosed (equipment / conductors) - Surrounded by a case, housing, fence, or wall(s) that
prevents persons from accidentally contacting energized parts.
Energized (see also “Live Parts” or “Hot Work”) - Electrically connected to or having a source
of voltage.
Exposed (as applied to live parts) - Capable of being inadvertently touched or approached
nearer than a safe distance by a person. It is applied to parts that are not suitably guarded, isolated,
insulated, or enclosed.
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Flame-Resistant (FR) - The property of a material whereby combustion is prevented, terminated, or
inhibited following the application of any source of ignition, with or without subsequent removal of the
ignition source.
Flash Hazard - A dangerous condition associated with the release of energy caused by an electric
arc.
Grounded - Connected to earth or to some conducting body that serves in place of the earth.
Guarded - Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers,
casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach or contact by
persons or objects to a point of danger.
Hot Work – Physically working on or nearby electrically energized equipment and parts
without barriers, guards or physical safe-guards in place.
Insulated - Separated from other conducting surfaces by a dielectric material (including air space)
offering a high resistance to the passage of electric current.
Isolated Equipment - Equipment that has been de-energized and “locked-out” according to the
UCB EI/LOTO Program procedures.
Labeled - Equipment or materials to which has been attached a label, symbol, or other identifying
mark of a “Listing” organization (such as an NRTL) that is acceptable to the AHJ. Labeled equipment
requires third-party product evaluation and periodic inspections of production of labeled equipment or
materials, and by such labeling the manufacturer indicates compliance with appropriate standards of
equipment performance and safety in a specified manner.
Limited Approach Boundary - A distance from an exposed live part within which an electrical
shock hazard exists for non-qualified personnel, unless escorted by a qualified worker. The Limited
Approach Boundary determines the minimum safe distance for the placement of barricades for shock
protection. An unqualified worker may not enter the limited approach boundary without escort by a
qualified worker.
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Listed - Equipment, materials, or services included in a list published by a “Listing” organization that is
acceptable to the AHJ and is concerned with evaluation of products or services, that maintains periodic
inspection of production of listed equipment or materials or periodic evaluation of services, and whose
listing states that the equipment, material or services either meets appropriate designated standards or
has been tested and found suitable for a specific purpose. “Listed” equipment will have the stamp of an
NRTL or “Listing Organization”.
Listing Organization – See “Nationally Recognized Testing Laboratory”.
Live Parts (see also energized) - Energized conductive components. Also known as “Hot Parts”
or “Electrically Hot”.
Nationally Recognized Testing Laboratory (NRTL) - Certain private sector organizations
recognized by OSHA as an NRTL. That recognition signifies that the organization has met the
necessary qualifications specified in the OSHA NRTL program. The NRTL determines that specific
equipment and materials (products) meet consensus-based standards of safety to provide assurance
that these products are safe for use in the U.S. workplace. E.g. Underwriters Laboratory (UL) is an
NRTL.
Overload - Operation of equipment in excess of normal, full-load rating or of a conductor in excess of
rated ampacity that, when it persists for a sufficient length of time, would cause damage or dangerous
overheating. A fault, such as a short circuit or ground fault, is not an overload.
Qualified Person - A person who has skills and knowledge related to the construction, installation,
maintenance and operation of electrical equipment and installations appropriate to the hazard level of
intended work, and has received safety training on the hazard controls involved in that work by their
supervisor.
Supervisor - This is a general term used throughout this program that is defined as a person who
oversees electrical work, and persons doing electrical work, and who have the primary responsibility of
ensuring a safe working environment. At UCB, ‘supervisors’ may include PIs, Researchers, Staff,
Project Managers and / or Contractors.
Shock Hazard - A dangerous condition associated with the possible release of energy caused by
contact or approach to live parts.
Verified De-energized (see also “electrically safe work condition”) - A state in which the
conductor or circuit part to be worked on or near has been disconnected from energized parts,
locked/tagged in accordance with the Energy Isolation /LOTO Program, tested to ensure the absence
of voltage, and grounded if determined necessary.
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Voltage (of a circuit) - This is the greatest root-mean-square (rms) difference of electrical potential
between any two conductors of a circuit.
Voltage to Ground - For grounded circuits, this is the voltage between the given conductor and the
part of the equipment / circuit that is grounded. For ungrounded circuits, this is the greatest voltage
between the given conductor and any other conductor of the circuit.
Working Near (energized / live parts) - Any activity inside a Limited Approach Boundary.
Working On (energized / live parts) – Conducting “Hot Work” using insulated tools, probes, or
test equipment to physically contact energized equipment / circuits, regardless of the personal
protective equipment a person is wearing on their hands, feet, or other body parts.
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5. Electrical Hazards and Controls
For basic information about Electricity and Electrical Safety, please review the “Frequently Asked
Questions / Fact Sheet” to become familiar with electrical hazards and controls.
5a. Electrical Hazards associated with work around electricity include:
Arc Flash
When an electric current passes through the air between two conductors, the temperature can reach
35,000F. Exposure to these extreme temperatures can result in life threatening burns. The majority of
hospital admissions due to electrical accidents are from arc-flash burns, not electrical shocks. Arcflashes can and do kill at distances in excess of 10 ft.
Arc Blast
The tremendous temperatures of the arc cause an explosive expansion of both metal and the
surrounding air in the arc path. For example, copper expands by a factor of 67,000 times when
changed from a solid into a vapor. The dangers of this explosion are of a high blast pressure wave,
high decibel levels of sound and high velocity shrapnel. The material and molten metal is expelled
away from the arc at speeds exceeding 700 miles per hour. Arc blasts often cause severe injuries and
death.
Burns
Burns suffered in electrical accidents are of two basic types: electrical burns and thermal contact burns.
Electrical burns cause tissue damage to skin and internal tissues because the body is unable to
dissipate the heat generated by current flowing through the body tissues. Typically, these burns are
slow to heal. Thermal contact burns are those normally experienced from skin contact with the hot
surfaces of overheated electric conductors.
Delayed Effects
Damage to the internal tissues may not be apparent immediately after contact with electricity. Delayed
internal tissue swelling and irritation are possible. Prompt medical attention can help minimize these
effects and avoid death or long-term injury.
Electrical Shock Hazards
Accidental contact with exposed electrical parts operating at a voltage greater than 50 volts to ground
and having a current greater than 5 milliamperes can cause serious injury or death. Fatal ventricular
fibrillation of the heart can be triggered by a current flow of as little as several milliamperes. Severe
injuries, such as internal burns, can occur even if the electricity does not pass through the vital organs
or nerves.
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5b. Hierarchy of Electrical Hazard Controls
……includes the following in order of effectiveness:
 Eliminate the hazard through application of the UCB Energy Isolation/Lock Out-Tag Out
Program.
 Mitigate the hazard by using engineering controls, such as “Listed” panels, shields or barriers, to
isolate personnel from the energized components.
 Reduce exposure to the hazard by using special tools such as double-insulated hand-tools,
fused instrument probes, and personal protective equipment (PPE) to protect personnel from
exposed hazardous electrical conductors.
 Apply administrative controls, such as the Electrical Hot Work Permit, Shutdown Request, or
Switching Procedure, assignment of a Safety Watch, and qualification training.
5b1. Energy Isolation / Lockout Tagout Program (EI/LOTO)
De-energizing exposed electrical components is the preferred and primary method of electrical
hazard control at UCB. The UCB Energy Isolation / Lock-out Tag-out Program details the
procedures for de-energizing and locking out all sources of energy prior to working on any
electrical equipment.
5b2. Engineering Controls
Engineering controls are the primary control measure used to reduce the potential for direct
contact with exposed and energized electrical components. Engineering controls include, but are
not limited to the following:
 Opaque or transparent non-conductive panels used as barriers. These barriers can have small
openings for tool access to allow troubleshooting, measurement, and/or calibration of equipment
with access panels open. This arrangement may also allow the safety interlocks to be closed
without installation of bypass circuitry.
 Rated non-conductive insulating shields or barriers for energized components that do not need
to be manipulated during the work.
 Ground Fault Circuit Interrupters (GFCI’s) to supply temporary power during construction,
remodeling, maintenance, repair, or demolition of buildings, structures, equipment or similar
activities. As required by the CEC, GFCI’s are used for all portable power tools, outdoor work,
work on or near conductive surfaces, for resistive heating elements such as heater tapes, wet
locations, rooftops, within 6 feet of any wet sink, bathrooms, kitchen, lab showers and eye-wash
stations, and other areas that could present an electrical shock hazard should the worker come
in contact with the energized conductor of a tool or instrument.
 Rated insulated barrier mats, floor coverings or gratings to isolate the worker from conductive
ground paths while working on exposed and energized electrical components.
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5b3. Personal Protective Equipment (PPE)
Qualified workers who are potentially exposed to electrical hazards that cannot be controlled
through EI/LOTO or some engineering means are provided with and properly use tooling and
personal protective equipment that is appropriate for the specific work to be performed and the
associated hazard level. PPE may include isolative gloves, face protection, flame-resistant
clothing, insulated tools, non-conductive shoes, insulated floor mats, etc.
5b4. Administrative Controls
Electrical safe work practices are applied during analysis, diagnostic, troubleshooting, and
manipulative work on energized equipment by a qualified person, having been trained and briefed
by a knowledgeable supervisor prior to commencement of the specific tasks the Supervisor/Project
Manager authorizes. Work is only performed on energized electrical circuits or components when it
is demonstrated that de-energization introduces additional or increased hazards, or is infeasible
due to equipment design or operational limitations. If work must be done “hot”, then application of
the “hot work permit” process outlined in Appendix 1 of this program must be followed.
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6. Electrical Safe Work Policy and Procedures
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UCB’s Electrical Safe Work Policy is as follows:
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All researchers, PIs, staff, project managers, contractors and students ensure they and others
around them are working in a safe manner. Everyone supports a “Stop Work Policy”. It is the
responsibility of everyone to exercise this policy when observing unsafe work conditions or
practices.
UCB complies with CalOSHA regulations, the California Electrical Code and other established
safety standards to reduce or eliminate the dangers associated with working with or around
electrical energy.
All electrical wiring and equipment complies with the California Electrical Code and CalOSHA
regulations for electrical safety and engineering.
Work on or near equipment operating within the electrical hazard conditions identified in this
document is performed in an electrically safe state (verified de-energized) or is formally
approved and documented through a “Hot Work Permit” process.
Anyone at UCB who works on or near hazardous energized electrical circuits or components must
be “qualified” and “authorized” prior to performing such work.
Work is only performed on energized electrical circuits or components operating at greater than
50 volts and capable of an electrical current greater than 5 milliamperes or power greater than
1000 watts when it is demonstrated that de-energization introduces additional or increased
hazards or is infeasible due to equipment design or operational limitations.
Energized parts that operate at less than 50 volts and less than 1000 watts are not required to be
de-energized if there will be no exposure to electrical burns or to explosion blast due to electric
arcs.
When work on energized electrical circuits or components operating at voltages greater than 50
volts to ground and capable of an electrical current greater than 5 milliamperes is justified and
approved, engineering controls (guards, covers, shields, insulated tools, fused probes, remote
methods, etc.) and personal protective equipment is used to reduce the potential for contact
with energized components.
All research or test devices operating at a voltage greater than 50 volts or storing more than 1000
watt/seconds (joules) is protected by an enclosure with secured or interlocked covers, or
isolated in a manner that will prevent inadvertent contact with exposed live parts.
Fabrication of research and test equipment is done following UCB design and engineering review
as prescribed in the Electrical Safe Work Program.
All electrically energized equipment is used in a safe manner as intended by the manufacturer
and within the equipment’s NRTL listing.
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6a. Electrical Safe Work – Administrative Procedures
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“Qualifying” and “Authorizing” Personnel
Only those persons who are both “qualified” and “authorized” may install, fabricate, repair, test,
calibrate, or modify electrical or electronics wiring, devices, systems, or equipment on UCB facilities or
property.
EXAMPLE: To help understand this concept, an example of this process in everyday life is that
someone with a valid driver’s license is ‘qualified’ by the state to drive a vehicle on public roads
through a series of book and road tests. But, they then must be ‘authorized’ to drive a specific
vehicle by the owner of that vehicle. Otherwise, “unauthorized” operation is considered autotheft even though they’re ‘qualified’ to operate a vehicle.
Similarly, a person may have the training and skills to be “qualified” by their Supervisor to work
on certain hazard-levels of electrical work, but may not be “authorized” by a Project Manager to
do the work on that Project Manager’s job-site.
Concerning Electrical Safety, a “qualified” and “authorized” person is an individual formally recognized
as:
 Having completed required classroom training, and
 Having sufficient understanding of a device, system, piece of equipment, or facility to be able to
recognize and positively control any hazards it may present, and
 Having completed site, area, facility, equipment and apparatus specific training, and
 Possessing the work experience and formal training necessary to execute the work according to
recognized and accepted technical standards, and
 Having qualifications and authorization documented by their Supervisor and/or Project Manager.
A person can be “qualified” and then “authorized” to work on specific equipment, or in certain locations,
or on certain projects but not the other way around. Persons may be “qualified” and then be
“authorized” to work on certain equipment or projects in one work situation or location, but not
authorized for another situation or location even though voltages and other electrical hazards and safework methods for both situations may be similar.
“Qualification” is generally approved and documented by the person’s Supervisor while “Authorization”
is generally approved by a Project Manager, Building Manager, PI, etc… In some cases, this may be
the same person. In many cases, it may not be the same person.
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General Guidelines for “Qualifying” Personnel
Qualification for electrical or electronics work is determined by the employee’s Supervisor or a Project
Manager. It is based upon a risk review of known electrical hazards in the work place versus the
known technical knowledge and safe-work expertise of the “qualified” worker.
A worker is determined “qualified” by the Project Manager or their Supervisor, when they can
demonstrate adequate knowledge to work safely with electricity through a combination of classroom
training (including required periodic retraining), formal electrical trade recognition, military, college or
other training, work experience, and on-the-job training. Formal training can be the completion of
apprenticeship, journeyman or comparable training. Experience may include formal technical related
education courses and hands-on field or classroom lab work that may or may not result in licenses or
certifications.
Specific “Qualifying Criteria”
Supervisors / Project Managers use the following guidelines to determine whether an individual is
“qualified” to perform specific electrical work. Different subsets of these criteria are selected according
to the exact nature of the task; however, some analysis is always performed, no matter how minor the
job. If the supervisor cannot verify a person’s qualifications, assistance from the PPCS Electrical
Engineer or the EH&S Safety Engineer should be obtained. At a minimum, the documentation of an
employee’s qualifications considers:
 The person’s ability to identify all possible hazards associated with a job task.
 The person’s ability to locate and read the appropriate engineering documents for the
equipment or facility.
 The person’s knowledge of how to check calibration, condition, and operation of equipment or a
facility.
 The person’s knowledge of how to shut down, isolate, and verify all sources of hazardous
energy.
 The person’s awareness of UCB EI/LOTO requirements, and training in LOTO.
 The person’s ability to identify, interpret and implement all applicable codes and standards
pertaining to a job task.
 The person’s experience and training to independently distinguish correct construction
techniques from incorrect techniques.
 The person’s experience and training to select the correct materials and components, and to
use them in a manner consistent with their manufacture and/or listing.
 The person’s ability to distinguish between appropriate and inappropriate equipment-grounding
techniques.
 The person’s experience, training and ability to predict all likely failure modes of a particular
construction, and to properly mitigate the effects of such failures.
 The person’s familiarity with the proper use of the special precautionary techniques, personal
protective equipment, including arc-flash, insulating and shielding materials, and insulated tools
and test equipment.
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If the person will be permitted to work within the Limited Approach Boundary of exposed energized
parts operating at 50 volts or more, the person is at a minimum additionally trained in UCB’s Electrical
Hot Work Procedure as outlined in Appendix 1 of this program.
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General Guidelines for “Authorizing” Personnel
Authorization to perform electrical or electronics work by a person at UCB is determined by their
Supervisor in conjunction with the Project Manager, and is based on the known ability of the person to
safely perform specific tasks around specific known hazards at specific locations, or specific equipment,
or on specific job sites. In many situations, the Supervisor and the Project Manager may be the same
person. But, in situations where they are two different people, a meeting to assess project hazards and
needed qualifications to complete safe electrical work must be held between the Supervisor and the
Project Manager before “authorizing” a “qualified” person to conduct electrical work on the Project
Manager’s project.
UCB Project Managers who engage the services of outside contractors who perform work on or near
energized electrical components must assure these contractors are appropriately “qualified” before
“authorizing” their work on specific projects.
Specific Authorizing Personnel Criteria
Only persons who are “Authorized” may conduct Electrical and/or Electronic work, or engage in Energy
Isolation / Lock out-Tag out processes on UCB facilities / property. Authorized Person(s) may develop
location-specific safe-work procedures and conduct annual audits on existing procedures as detailed
below.
The Supervisor / Project Manager “authorizes” persons to perform work tasks only if they are satisfied
that all relevant safe-work criteria are met concerning a specific job-site or location. On-the-job
orientation for specified equipment, types of equipment, or specific facility location(s) is documented to
ensure that training is adequate and consistent for all personnel with similar tasks. This documentation
is reviewed and approved by a person who is knowledgeable in safe electrical work practices, and is
familiar with the hazards involved in the work. This orientation / training covers:
 A detailed description of the scope of the work task being considered.
 The person’s experience in the selection and use of test equipment for this task.
 Features and hazard review of the facility or equipment, including any specialized configuration.
 Relevant documents such as wiring diagrams, schematics, service manuals, and operating,
testing, and calibration procedures.
 Location of all energy sources to, and within, the facility / equipment.
 Location of all energy-isolating devices.
 The system's energy control procedures, including energy-isolating devices, grounding and
shorting procedures, and other energy-control procedures.
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The person’s thorough familiarity with specific equipment-grounding requirements for this
apparatus.
Techniques, tools, and personal protective equipment (PPE) including arc-flash PPE used for
the specific equipment / facility locations
The person’s knowledge of the nearest location of a telephone and how to alert emergency
rescue personnel.
If the person will be permitted to work within the Limited Approach Boundary of exposed
energized parts operating at 50 volts or more, the person at a minimum additionally must be
“qualified” and “authorized” to do the work at the specific location / job site according to UCB’s
Electrical Hot Work Procedure as outlined in Appendix 1 of this program.
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Electrical Safety Committee (ElSC)
The ElSC is comprised of members from departments impacted by this program and has the
responsibility to implement the UCB Electrical Safe Work Program in the UCB built environment.
Permanent members of the ElSC include the Electrical Engineer (PP-CS) and Safety Engineer (EH&S).
In addition, the ElSC is comprised of members in affected departments who are knowledgeable in
electrical safety, electrical systems, electrical equipment, and electrical requirements and standards
(CalOSHA, NFPA, CEC, and ANSI as appropriate). At minimum this includes one electrical supervisor
from PP-CS and RSSP, four electrical trades-persons from representative shops. In addition, the
Campus Safety Engineer will invite DSCs and Researchers to be members of the ElSC in departments
with electrical safety hazards / exposures. The ElSC meets at minimum quarterly for one hour, and
more frequently as need dictates. Members of the ElSC elect a Chair-person to oversee operations of
the committee, call meetings, etc…. The position of the Chair-person is held for four sessions (one year
minimum). The Chair-person is responsible for maintaining documentation of committee activities.
Responsibilities of the ElSC are outlined in that section of this program document, and include the
application of the requirements of this document throughout campus and other UCB properties.
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Procurement of Contract Services for Electrical Work
UCB Project Managers who engage the services of outside electrical contractors must assure they are
appropriately “Qualified” before “Authorizing” them to work on campus when seeking a Purchase
Requisition for Contracted Services.
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Developing Purchase Requisition documentation:
Contractors may be engaged to modify, install or repair premises wiring or electrical equipment at UCB
under purchase orders, service contracts or blanket purchase orders for service. To safely control this
process the person initiating the purchase request for these services are responsible for completing the
following supporting documents:
1. Electrical hazard assessment involved in the planned work based upon available voltages
(Attachment B) and whether the work must be done “live/hot”, or whether the circuits can be
shut off and isolated following the UCB Energy Isolation / LOTO Program.
2. Required qualifications of the contractor performing the work (Attachment C) as part of the
“purchase requisition” request, and
3. A “Shut-Down Request Form” (Attachment H) if electrical shut-down work is included as part of
the planned contract work. The “Shut Down Request” must be signed off by the campus
Electrical Engineer and/or the Facility’s Manager at a specific job-site prior to issuing the
Purchase Order.
Other contractor-specific qualifications may be used if deemed as equivalent and agreed to in writing by
the EHS Safety Engineer and/or the PPCS Electrical Engineer. In addition, EH&S Safety Engineer or
other management may impose additional safety requirements on the work to ensure that the work is
done safely, and does not present an unexpected hazard to anyone.
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Electrical Distribution Systems (Premises Wiring / Facility Wiring)
Who does the work:
Only qualified and authorized personnel are allowed to perform electrical wiring or other work directly
connected to any facility electrical distribution system (premises wiring as defined by the CEC).
Premises wiring includes that portion of utilization equipment that is permanently connected (hardwired) to the facility electrical distribution system, viewed from the utilization equipment’s first
disconnect (or circuit breaker) looking backward into the premises wiring. Connection to, and diagnosis
and repair of, circuit breakers in building electrical panels may only be done by specified qualified and
authorized electrical workers.
Who approves “Hot Work”:
UCB work crews and / or contractors must coordinate their work with the UCB Project Manager and
must not perform any Hazard Class B, C, or D (Attachment B) Electrical Hot Work without prior
submission and subsequent approval of a completed Hot Work Permit (Attachment I) or previously
approved equivalent) to the UCB Electrical Engineer and UCB Project Manager.
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Who approves Isolation or Shut-down work:
No work requiring EI - LOTO or shut down of campus facilities will be performed without prior
submission and subsequent approval of a completed Shutdown Request Form (Attachment H) to the
UCB Electrical Engineer and/or Facility Manager. The UCB Project Manager, Electrical Engineer,
Safety Engineer or other management may impose additional safety requirements on the work to
ensure that the work is done safely and does not present an unexpected hazard to anyone. This may
include providing additional safeguards such as protective barriers, posting a UCB qualified person at
the work site to control access, or other safety measures as may be required to ensure safe working
conditions for UCB personnel and contract workers.
Who approves contractor work:
When contractors modify, install or repair premises wiring at UCB under purchase orders, service
contracts or blanket purchase orders, the UCB Project Manager must know the nature and extent of
work to be done including associated hazards. The UCB Project Manager informs contractors of
known hazards, and contractors must follow the safety requirements and procedures of the contractor’s
IIPP safe-work practices to provide a level of electrical safety consistent with this program and the
requirements of the State of California.
Capital Projects – Hot Work Exception:
It is the responsibility of the UCB “Capital Projects” Project Manager to initiate and coordinate with
PPCS and EHS any “Capital Projects Hot Work” and cannot delegate this responsibility to the
Contractor. For situations where Contractors are working on large projects that routinely require
Electrical Hot Work Permits, project contractors may perform this work under their local (job site) HotWork Permits if their work:
1. Does not affect any campus facility beyond the immediate and total control of the project (that is,
within the project boundary), and
2. Does not require any shut down or isolation of campus electrical services, and the
3. Project’s “Permitting Plan” is pre-approved by the UCB campus Electrical Engineer and EHS
Safety Engineer prior to start of work on the project.
Go to Table of Contents
Go to “How this program applies to you”.
Electrical Equipment Work
(Both Research Apparatus and Facility Equipment)
Who does the work:
Only qualified persons may fabricate, modify, install or repair electronic or electrical equipment used at
UCB. Supervisors are responsible for ensuring that only qualified persons under their supervision are
assigned to work on electronic or electrical equipment at UCB. The supervisor ensures the
qualifications of these employees are documented.
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Who approves “Hot Work”:
UCB researchers and / or contractors working for researchers must not perform any Hazard Class B, C,
or D (Attachment B) Electrical Hot Work without prior submission and subsequent approval of a
completed Hot Work Permit (Attachment I) or previously approved equivalent to the UCB EH&S Safety
Engineer.
Who approves Isolation or Shut-down work:
No work requiring isolation or shut down of campus facilities will be performed without prior submission
and subsequent approval of a completed Shutdown Request Form (Attachment H) to the UCB P
Electrical Engineer. The UCB Project Manager, Electrical Engineer, Safety Engineer or other
management may impose additional safety requirements on the work to ensure that the work is done
safely and does not present an unexpected hazard to anyone as necessary. This may include providing
additional safeguards such as protective barriers, posting a UCB qualified person at the work site to
control access, or other safety measures as may be required to ensure safe working conditions for UCB
personnel and contract workers.
Who approves contractor work:
When researchers employ contractors to modify, install or repair electronic or electrical equipment at
UCB under purchase orders, service contracts or blanket service purchase orders, the UCB Property
Custodian of the equipment must know the nature and extent of work to be done including associated
hazards. The UCB Property Custodian informs researchers and contractors of known hazards.
Contractors must follow the safety requirements and procedures of the contractor’s IIPP safe-work
practices to provide a level of electrical safety and hazard control consistent with this Program.
Contractors must coordinate their work with the with the Property Custodian and shall not perform any
Hazard Class B, C, or D (Attachment B) Electrical Hot Work without prior submission and approval of a
completed Hot Work Permit (Attachment I) to the UCB EH&S Safety Engineer. No work requiring
isolation or shut down of campus facilities will be performed without prior submission and approval of a
completed Shutdown Request Form (Attachment H) or previously approved equivalent) to the UCB
Electrical Engineer. The UCB Equipment Custodian, campus Electrical Engineer, EH&S Safety
Engineer or other management may impose additional safety requirements on the work to ensure that
the work is done safely and does not present an unexpected hazard to anyone as necessary. This may
include providing additional safeguards such as protective barriers, posting a UCB qualified person at
the work site to control access, or other safety measures as may be required to ensure safe working
conditions for UCB personnel and contract workers.
Go to Table of Contents
Go to “How this program applies to you”.
Electrical Research Equipment Design and Installation:
All researchers who design, develop and install electrical equipment as part of their research, even as
temporary installations, must design and install their apparatus to comply with the guidance of
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UC Berkeley Electrical Safety Program
(Attachment K), Electrical Equipment Safe Work Space Requirements, and (Attachment L), Research
Equipment Fabrication and Maintenance. In addition, there are detailed requirements for developing /
designing / installing / maintaining / modifying the following types of electrical equipment as part of
research:
Attachment M:
Attachment N:
Attachment O:
Attachment P:
Attachment Q:
Attachment R:
Attachment S:
Attachment T:
Attachment U:
Attachment V:
Practices for Heating Tapes and Cords
Practices for Flexible Cords
Use of Extension Cords
Practices for Portable Workbenches
Practices for Power Supplies
Practices for Capacitor Hazards
Practices for Inductor and Magnet Hazards
Practices for Control and Instrumentation Design
Practices for Ground Fault Circuit Interrupters (GFCIs)
Nationally Recognized Testing Labs and Symbols
Please contact the EH&S Safety Engineer to support and guide safe electrical equipment design and
installation in your research activities.
Go to Table of Contents
Go to “How this program applies to you”.
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UC Berkeley Electrical Safety Program
6b. Electrical Safe Work – Job-site Procedures:
General Safe Work Rules
All researchers, PIs, staff, project managers, contractors and students with potential for exposure to
electrical hazards must:
 Identify hazards and anticipate problems.
 Resist “hurry-up” pressure.
 Don’t hesitate to use the Stop Work Policy.
 Know and apply the UCB EI/LOTO Program and Procedure.
 Positively ensure the correct circuit is identified before lockout and tagout.
 Whenever possible de-energize the equipment before testing.
 Assure the supervisor, or their designee, conducts a safe work briefing with all personnel in the
area before commencing any energized electrical work.
 Always consider electrical equipment energized until positively proven otherwise.
 Use suitably rated electrical tools and devices only as intended.
 Remove all jewelry before performing energized electrical work.
 Know how to shut down equipment in an emergency.
 Know UCB emergency procedures.
 Design and plan for safety.
 Reset a circuit breaker only one time for a given event and only after the cause has been
identified and rectified.
 Maintain the protection of covers, barriers and shielding of all electrical equipment.
 Never drill into a wall or floor slab without approval of the Building Manager and Electrical
Engineer.
 Never modify or penetrate premises wiring conduit or enclosed wire ways.
 Assure only qualified and authorized persons are allowed to work on premises wiring, conduits
or enclosed wiring.
 If you must work “hot”, always position yourself so you fall away from the equipment. If
something goes wrong, you do not want a shock or arc to cause you to fall into any exposed
wiring or bus. This simple work practice has saved many lives and prevented a lot of pain and
misery. Remember, always make gravity your friend!
Go to Table of Contents
Go to “How this program applies to you”.
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UC Berkeley Electrical Safety Program
Energized “Hot Work” Electrical Work Requirements
It is UCB policy to de-energize live parts whenever possible before anyone works on or near them.
This is the preferred method for protecting everyone from electrical hazards. Personnel follow the UCB
Energy Isolation – Lock out Tag out Program to safely de-energize live parts prior to working on them.
Personnel are permitted to work on or near exposed live parts only if it is demonstrated that
de-energization:
 Introduces additional or increased hazards, or
 Is infeasible due to equipment design or operational limitations, or
 Creates other hazards for life-safety on a case-by-case basis.
If it has been demonstrated that a work task cannot be accomplished in a verified de-energize
condition, then Appendix 1 – “Energized “Hot Work” Electrical Work Procedures must be followed.
Energized parts that operate at less than 50 volts need not be de-energized if there is no increased
exposure to electrical burns or to explosion blast due to electric arcs. Exceptions to this exemption
include low-voltage DC battery banks with available amperages in excess of 1000 amps. This
exception may also not apply for situations less than 1000 amps in some situations. Refer to
Attachment B to determine the hazard class of your equipment and apply safe-work rules accordingly.
Go to Table of Contents
Go to “How this program applies to you”.
7. Training Requirements
Training requirements for personnel on the sections of this program that impact their work are noted
below. Training is based upon hazard exposure assessment, and may be delivered every three years
up to annually as noted below by job activity, or in the “Training Qualifications” for personnel “qualified
to work hot”. Training methods may include the online LMS, general safety training in offices, labs,
shops and work environments, familiarization with UCB’s Energy Isolation / LOTO Program, specific
training on the procedures outlined in this program, as well as work-site tail-gate meetings and safework planning efforts. Based upon the type of electrical work being considered, review the training
requirements below to assure adequate training for you, your department and your co-workers.
All Faculty, Staff and Students receive general electrical safety training as part of UCB orientation
and general IIPP safety training on the roles and responsibilities outlined for everyone in this program.
This includes review of Attachment O: Use of Extension Cords.
Go to Table of Contents
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UC Berkeley Electrical Safety Program
Trades Persons and others doing Electrical Work
On-going electrical and electronics training includes an annual review of this program and all
appendices pertinent to the trainee’s work assignment as well as the campus EI/LOTO Program.
Additional training may include tail-gate discussion of safe-work planning on the job-site based upon
electrical work they will be doing in the hazard classes outline in (Attachment B), and required safe
electrical work practices as outlined by (Attachment C), as well as the Hot-work Permit Procedure
including Appendix 1, Attachments A – I, and any other pertinent training(s) identified by the
employee’s Supervisor.
Go to Table of Contents
Go to “How this program applies to you”.
Supervisors (includes PIs, Researchers, Staff and / or Project Managers)
Supervisors have the same program information training that Trades Persons doing electrical work
have. In addition, Supervisors who oversee electrical work receive more detailed training from EH&S
on Electrical Hazard Identification and Control strategies, detailed knowledge of the procedures
contained in this entire program document, documented education and on-the-job training, and may
obtain professionally recognized credentialing. Supervisors also receive full training on of application of
UCB’s Energy Isolation / LOTO Program and additional training as may be outlined by Supervision of
work in the Hazard Classes noted in (Attachment C) as well as the Hot-work Permit Procedure
including Appendix1 (Attachments A – I).
Go to Table of Contents
Go to “How this program applies to you”.
Researchers, PIs, and Staff that hire Electrical Contractor Services
Persons who oversee contractor electrical work receive more detailed training from EH&S on Electrical
Hazard Identification and Control strategies and detailed knowledge of the “Procurement Procedures”
contained in this program document. These persons also receive training on application of UCB’s
Energy Isolation / LOTO Program. Included is the familiarization with, and use of, the following:
Appendix 1 – Hot Work Permit Procedure
Attachment K: Electrical Equipment Safe Work Space Requirements
Attachment L: Research Equipment Fabrication and Maintenance
Attachment M: Practices for Heating Tapes and Cords
Attachment N: Practices for Flexible Cords
Attachment O: Use of Extension Cords
Attachment P: Practices for Portable Workbenches
Attachment Q: Practices for Power Supplies
Attachment R: Practices for Capacitor Hazards
Attachment S: Practices for Inductor and Magnet Hazards
Attachment T: Practices for Control and Instrumentation Design
Attachment U: Practices for Ground Fault Circuit Interrupters (GFCIs)
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UC Berkeley Electrical Safety Program
Attachment V: Nationally Recognized Testing Labs and Symbols
Attachment W: Electrical Safe-work Specifications for Construction Projects
Attachment X: Electrical Arc-Flash Specifications for Building Construction
Go to Table of Contents
Go to “How this program applies to you”.
Researchers, PIs, and Staff who work in research designing, developing and
installing electrical equipment
Researchers / Supervisors have the same program information training that Trades Persons doing
electrical work have. In addition, Supervisors who conduct or oversee electrical work receive more
detailed training from EH&S on Electrical Hazard Identification and Control strategies, detailed
knowledge of the procedures contained in this entire program document, documented education and
on-the-job training, and may obtain professionally recognized credentialing. Supervisors also receive
full training on of application of UCB’s Energy Isolation / LOTO Program and additional training as may
be outlined by Supervision of work in the Hazard Classes noted in (Attachment C). Also included is the
familiarization with, and use of, the following:
Appendix 1 – Hot Work Permit Procedure
Attachment K: Electrical Equipment Safe Work Space Requirements
Attachment L: Research Equipment Fabrication and Maintenance
Attachment M: Practices for Heating Tapes and Cords
Attachment N: Practices for Flexible Cords
Attachment O: Use of Extension Cords
Attachment P: Practices for Portable Workbenches
Attachment Q: Practices for Power Supplies
Attachment R: Practices for Capacitor Hazards
Attachment S: Practices for Inductor and Magnet Hazards
Attachment T: Practices for Control and Instrumentation Design
Attachment U: Practices for Ground Fault Circuit Interrupters (GFCIs)
Attachment V: Nationally Recognized Testing Labs and Symbols
Go to Table of Contents
Go to “How this program applies to you”.
Associate Vice Chancellor of Facility Services and the EH&S Director receive basic
electrical safety training from EH&S Safety Engineer, familiarization with the contents of this entire
program document, and high-level strategy updates on program effectiveness from the Electrical Safety
Committee.
PPCS / Campus Electrical Engineer receives updates and continuing educational developments
in electrical safety as part of ongoing professional development activities. In addition, the Campus
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UC Berkeley Electrical Safety Program
Electrical Engineer imparts new knowledge to affected sections of this program through the program
review process and involvement with the Electrical Safety Committee.
Go to Table of Contents
Go to “How this program applies to you”.
EH&S / Campus Safety Engineer receives updates and continuing educational developments in
electrical safety as part of ongoing professional development activities. The Campus Safety Engineer
imparts new knowledge to affected sections of this program through the program review process and
involvement with the Electrical Safety Committee.
Electrical Safety Committee (ElSC) receives updates and continuing educational developments
in electrical safety as part of ongoing professional development activities. Imparts new knowledge to
affected sections of this program through program review process and involvement with external
certifying organizations and training opportunities. Makes regular recommendations for Electrical Safe
Work Program changes to EH&S Safety Engineer as well as updates as compliance issues, lessons
learned and other safe-work opportunities are adopted into the program by the Committee.
Go to Table of Contents
Go to “How this program applies to you”.
8. Record Keeping Requirements
Hot Work Permits, Shut Down Requests, Switch Logging, etc. documentation requirements
are based upon Hazard Class determination (Attachment B), tracing of the individual project’s hazard
assessment using the Hot Work Flow Chart (Attachment A) and the process as outlined in (Appendix
1).
Go to Table of Contents
Supporting documentation, Purchase Orders, RFPs, etc. for Contracted Electrical Work are
kept by the Supervisor / Project Manager for 7 years beyond the date of project completion, and must
be made available for review to EH&S personnel upon request.
Go to Table of Contents
Approvals for Energized Electrical “Hot Work” (Briefings, Shut Down Requests, Electrical
Hot Work Permits, Switching Procedures, and other Specific Procedures) are maintained by the
supervisor of the person(s) performing the work for at least three years. Energized Electrical Work
Approvals are made available to EH&S personnel upon request.
Go to Table of Contents
Training records, Tail-Gates and Work-site Orientations include the name and signature of
the trainee, the date and content of the training, and evidence of successful comprehension, are kept
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UC Berkeley Electrical Safety Program
on file for a period in accordance with UCB records retention policies via the Learning Management
System database. For training not documented by the LMS, records are kept by the Supervisor of the
trainees performing the electrical work for 7-years beyond the date of project completion, and must be
made available for review to EH&S personnel upon request.
Go to Table of Contents
Qualification Determination Records (e.g. resumes, job applications, military training records,
on-the-job training records, etc.) are kept on file by hiring department’s HR staff, with copies provided to
Supervision as necessary, for the duration of the personnel’s work-time at UCB plus 7-years.
Qualification records are renewed annually by the electrical worker’s Supervisor by completion of
Attachment D2 with copies filed in the electrical worker’s personnel work file. Documentation must be
made available for review to EH&S personnel upon request.
Go to Table of Contents
Authorization Records are kept on file by Project Supervision with copies provided to the
Authorized Worker, for the duration of the personnel’s work-time at UCB plus 7 years. Documentation
must be made available for review to EH&S personnel upon request.
Go to Table of Contents
Go to “How this program applies to you”.
9. References
California Code of Regulations, Title 24, Part 3
http://www.bsc.ca.gov/title_24/t24_2005_ccr.htm
California Code of Regulations, Title 8, Subchapter 5, Electrical Safety Orders
http://www.dir.ca.gov/Title8/sub5.html
UC Berkeley Energy Isolation and Lockout – Tag Out Program
Issued By and Next Review Date
This program is issued / adopted on June 15, 2010 by Mark Freiberg, Director, EH&S, UC Berkeley
under direction of the Chancellor.
This program is reviewed and updated every 3 years or as recommended by the Electrical Safety
Committee and determined necessary by the campus Electrical Engineer or EH&S Safety Engineer.
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UC Berkeley Electrical Safety Program
10. Appendix and Attachments
Go to Table of Contents
Go to “How this program applies to you”.
Appendix 1 – Hot Work Permit Procedure
Attachment A: Energized Electrical Work Flow Chart
Attachment B: Electrical Hazard Classification and Requirements
Attachment C: Qualification Training Requirements
Attachment D1: Project Documentation Requirements
Attachment D2 – Personnel Hot Work Qualification – Annual Documentation
Attachment E: Shock Protection Approach Boundaries
Attachment F: Flash Protection Boundary
Attachment G: Protective Clothing Characteristics
Attachment H: Shut Down Request Form
Attachment I: Electrical Hot Work Permit
Attachment J: Switching Log Form
Attachment K: Electrical Equipment Safe Work Space Requirements
Attachment L: Research Equipment Fabrication and Maintenance
Attachment M: Practices for Heating Tapes and Cords
Attachment N: Practices for Flexible Cords
Attachment O: Use of Extension Cords
Attachment P: Practices for Portable Workbenches
Attachment Q: Practices for Power Supplies
Attachment R: Practices for Capacitor Hazards
Attachment S: Practices for Inductor and Magnet Hazards
Attachment T: Practices for Control and Instrumentation Design
Attachment U: Practices for Ground Fault Circuit Interrupters (GFCIs)
Attachment V: Nationally Recognized Testing Labs and Symbols
Attachment W: Electrical Safe-work Specifications for Construction Projects
Attachment X: Electrical Arc-Flash Specifications for Building Construction
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UC Berkeley Electrical Safety Program
Appendix 1 – Hot Work Permit Procedure
Go to Table of Contents. Go to “How this program applies to you”.
Go to Hot Work Procedure.
Introduction:
“Hot” electrical work is defined as any kind of work on conductor(s) that are energized and have 50 volts or
greater, AND 5 milli-Amps or greater, of electrical potential. If conductors are isolated per the UC Berkeley
Energy Isolation Program using OSHA-approved Lock out / Tag out techniques, then the circuits are NOT
considered ‘hot’ and general work may commence without a ‘hot work’ permit.
This “Hot Work Permit” procedure DOES NOT APPLY to research apparatus and research instrumentation
manufactured by a reputable manufacturer that is approved by an NRTL. The NRTL must approve the
apparatus as having continuous safety-monitoring ground-fault circuit interruption of exposed conductors
powered by the apparatus, and built into the control circuit of the apparatus. Examples of such apparatus
include Electrophoresis Power Supplies and newer High-Pot Test apparatus built since 2005 with such
safety-protection built in.
UCB Electrical “Hot Work Policy”:
It is University policy to only work energized or ‘hot’ when no other means to isolate and lock out electrical
circuits is practical. When the need to do electrical ‘hot’ work is encountered, any UCB Project Manager, PI,
Supervisor, or other person conducting, ordering or procuring electrical hot work, must complete the
following procedural steps to conduct a hazard analysis of the electrical work, and assure properly trained
and prepared personnel with all needed safe-work hazard controls are oriented and present prior to
commencing ‘hot’ work at any jobsite or on any equipment.
Who May Conduct Electrical “Hot Work”:
Only “Authorized and Qualified” personnel are allowed to do “hot work”. Only knowledgeable Supervisors
and/or an Electrical Engineer may authorize and sign a “Hot Work Permit” or “Authorize and Qualify” a
person to conduct Electrical Hot Work.
Exemption of “Who May Conduct Hot Work”:
“Testing and Troubleshooting” often require a circuit and equipment to be temporarily energized. The
“Testing and Troubleshooting” exemption applies only when no actual modification or manipulating of
energized electrical conductors or components will take place, and equipment / safe work practices are
otherwise under UCB Energy Isolation / Lock-out Tag out program rules.
Please refer to the end of this Appendix for definitions of terms used in this Hot Work Procedure document.
Energized Electrical Work “Hot Work” Procedure – 9 Steps
Click here to download this form as a .pdf file.
Back to Appendix 1 Introduction
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UC Berkeley Electrical Safety Program
1. Determine if there is an option to de-energize and isolate the equipment per the UCB Energy Isolation
Program. If equipment can be isolated so that electricity is shut off and locked / tagged out, complete
and submit a “Shut Down Request Form” (Attachment H) to the PP-CS Shut-down Desk at
[email protected] or contact the Call Center (642-1032) to arrange safe deenergization of equipment.
2. Work may ONLY be done energized “hot” if de-energization of the work:



Introduces additional or increased hazards, or
Is infeasible due to equipment design or operational limitations, or
Creates other hazards for life-safety on a case-by-case basis
3. If work must be done “electrically hot” due to meeting one of the above criteria, the Project Manager /
Supervisor proceeds to implement the Hot-Work Permit Process Flow Chart Attachment A by following
these “Hot Work” procedural steps, printing out, circling/line tracing the pathway through Attachment A
for each and every piece of equipment requiring “Hot Work” to be performed on it. Save each completed
Attachment A as part of any project documentation.
4. Determine the Hazard Class of the task referencing Attachment B and determine if the “General Safe
Work Procedure”, the “Two Person Rule” and/or the “Electrical Safety Watch Rules” are to be enacted as
part of the safe work plan.
5. Determine the Required Qualifications of personnel to perform the task referencing Attachment C.
6. Determine and complete the Required Documentation to perform the task using Attachment D1 and
document proper “Authorization and Qualification” of each worker using Attachment D2.
7. If an Electrical Hot Work Permit is required:
a) Identify and set up the Shock Protection Boundaries (Attachment E).
b) Identify and set up the Flash Protection Boundary (Attachment F).
c) Obtain the appropriate Tools and wear the proper PPE. (Attachment G).
d) Complete the Electrical Hot Work Permit (Attachment I).
e) Obtain signature approval on the permit from Project Manager / Supervisor to proceed with the task.
8. If required by campus Electrical Engineer, Project Manager or Supervisor, develop a specific step-by-step
shut down procedure by completing the Switching Log (Attachment J). Train all jobsite personnel on
these procedures prior to commencing work.
9. Implement hazard control requirements and perform the hot-work task as outlined in the “Hot Work”
permit and Switching Log procedure.
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UC Berkeley Electrical Safety Program
Attachment A – Hot Work Flow Chart / Checklist
Go to “How this program applies to you”.
Go to Hot Work Procedure.
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
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UC Berkeley Electrical Safety Program
General Electrical Safe Work – Jobsite Procedures
Back to Hot Work Procedure
All researchers, PIs, staff, project managers, contractors and students with potential for exposure to
electrical hazards must:
 Design and plan for safe work, identify hazards and anticipate problems.

Resist “hurry-up” pressure and don’t hesitate to use the “Stop Work Policy” when hazards are identified.

Know and apply the UCB EI/LOTO Program and Procedure.

Whenever possible de-energize the equipment before testing.

Positively ensure the correct circuit is identified before lockout and tagout.

Always consider electrical equipment energized until positively proven otherwise.

Assure the supervisor, or their designee, conducts a safe work briefing with all personnel in the area
before commencing any energized electrical work.

Use suitably rated electrical tools and devices only as intended.

Remove all jewelry before performing energized electrical work.

Know how to isolate all energy sources to equipment in an emergency.

Know UCB emergency procedures for your work location.

It is strongly recommended that a tripped circuit breaker only be reset by an “Authorized and Qualified”
person who has the skills and knowledge to trouble-shoot, understand the cause, and safely re-energize
the circuit. Report all tripped circuit breakers to Building Management, or to your Supervisor if you are
doing the electrical work, regardless of cause or circumstances.

Maintain the protection of covers, barriers and shielding of all electrical equipment.

Be aware of hidden raceways and other utilities that may be concealed behind walls and/or concealed
below or in concrete walls and slabs. Facility As-Built Drawing Reviews, Metal detectors, Proximity
Detectors or X-ray methods must be employed prior to Saw Cutting or Core Drilling.

Never penetrate premises wiring conduit or enclosed wire ways.

If you must work “hot”, always position yourself so you fall away from the equipment. If something goes
wrong, you do not want a shock or arc to cause you to fall into any exposed wiring or bus. This simple
work practice has saved many lives and prevented a lot of pain and misery. Remember, always make
gravity your friend!

Assure only qualified and authorized persons are allowed to work on premises wiring, conduits or related
systems and equipment.
Back to Hot Work Procedure
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UC Berkeley Electrical Safety Program
Electrical Two-Person Rules
Back to Hot Work Procedure
Certain work requires two qualified persons. This occurs when work is considered electrically hazardous, as
established by the Hazard Class (Attachment B), or by the work supervisor. When the "Two-Person Rule" is
required, both workers must be present at the work site, both workers must plan ahead and be aware of the
other worker's tasks, and both workers must:
1. Be a qualified person.
2. Be authorized to de-energize equipment by their Supervisor.
3. Know the location of nearest telephones, and how to alert emergency rescue personnel.
4. Be able to free an injured worker from the hazard without putting themselves at risk.
5. Be trained and current in cardiopulmonary resuscitation (CPR / AED).
6. Be trained and current in First Aid.
7. Remain in visual and audible contact with the workers performing the work and no more than 50
feet away at any time.
Under limited conditions, the Electrical Two-Person Rule may allow an exemption for a second person that is
not a qualified person. To allow this exemption, all of the remaining requirements of the Two Person Rule
above apply, and in addition the following must be met:
1. The Supervisor must approve this exemption.
2. During the briefing process the qualified person will assess the qualifications of the second
person to determine that the work may proceed safely.
3. The second person must be trained and current in First Aid and CPR/AED.
4. The second person may not enter the Limited Approach boundary or the flash protection
boundary.
5. The electrical disconnecting means must be located outside of the limited approach boundary
and the flash protection boundary.
6. Both persons must be able to readily communicate with each other.
7. The electrical disconnect must be located within 50 feet and within sight of the second person.
8. The second person must be briefed in emergency procedures and the electrical work being
performed.
Minimum Electrical Safety Equipment to have staged at the jobsite prior to starting work includes:
1. ABC Dry-type fire extinguisher
2. First Aid Kit
3. Insulation floor matt / blanket / arc shield (if necessary)
4. Required Personal Protective Equipment and insulated tools
5. Boundary Marking Tape
6. Communication means / radio / cell phone
Back to Hot Work Procedure
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UC Berkeley Electrical Safety Program
Electrical Safety Watch Rules
Back to Hot Work Procedure
A Safety Watch is a more stringent hazard control measure than the Two-Person Rule and is implemented
when there are grave consequences from a failure to follow safe-work procedures. This occurs when work is
considered high-hazard electrical work, as established by the Hazard Class, or by the work supervisor. When
a Safety Watch is required, the Safety Watch is a qualified person who is responsible for monitoring the
qualified person(s) doing the work. A Safety Watch must:
1. Be a qualified person
2. Have no other duties that preclude continually observing, coaching, and monitoring for potential
hazards and mistakes
3. Have a thorough knowledge of the specific working procedures to be followed and the work to be
done; and
4. Be close enough to the work in progress to safely monitor the progress and methods of the
qualified person doing the work.
5. Use clothing and PPE appropriate to the hazard and the distance from the work in progress. In no
case should the Safety Watch be more than 50 feet from the qualified person (s) performing the
work.
6. Ensure only qualified persons are allowed to enter the Limited Approach Boundary.
7. Ensure that the Limited Approach Boundaries are properly barricaded and controlled.
8. If signs and barricades do not provide sufficient warning and protection for the Limited Approach
Boundary, an attendant, (third person), shall be stationed to warn and prevent unqualified
persons from entering.
Minimum Electrical Safety Equipment to have staged at the jobsite prior to starting work includes:
1. ABC Dry-type fire extinguisher
2. First Aid Kit
3. Insulation floor matt / blanket/ arc shield (if necessary)
4. Required Personal Protective Equipment and insulated tools
5. Boundary Marking Tape
6. Communication means / radio / cell phone
Back to Hot Work Procedure
Page 48 of 96
UC Berkeley Electrical Safety Program
Attachment B: Electrical Hazard Classification and Requirements
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Class
Criteria
Work Rules
A
LowHazard
Operation
Injury not likely.
Characterized by AC and/or DC Voltage less than or
equal to 50 Volts
----------------------------------------------------For voltages greater than 50 volts but with less than
5mAmps available – See note 1 below.
Follow basic office / lab
electrical safety rules.
B
MediumHazard
Operations
C
Hazardous
Operations
D
HighHazard
Operations
Potential for severe injury or death.
Characterized by voltage greater than a
Class “A” hazard.
AC and DC Voltage from
Greater than 50 to 250 volts.
----------------------------------------------------DC 50 Volts or less – See Note 2 below
Potential for severe injury or death is greater.
Characterized by voltages greater than a
Class “B” hazard.
AC and/or DC Voltage from
Greater than 250 to 600 volts.
----------------------------------------------------DC 50 Volts or less, but 1000 – 10,000 Amps
Potential for severe injury or death is greatest.
Characterized by voltages greater than a
Class “C” hazard.
AC and/or DC Voltage above 600 volts.
----------------------------------------------------DC 50 Volts or less, but Greater than 10,000 Amps
In addition to the above, follow
the General Electrical Safe-work
Rules.
In addition to the above, apply
the Two-Person Rule
Follow General Electrical Safework rules and implement
“Safety Watch” for all “hot work”.
(A total of 2 or more
“Qualified Persons” at the work
site is required.)
NOTES:
1. All-voltage sources up to 20kV with available fault currents less than 5 mA are considered a Class
“A” hazard.
2. DC power 50 volts or less, but with arc-flash potential of 5 mA – 1000 Amps has significant flashburn / fire potential for direct short to ground (e.g. dropping a metal tool across battery-bank output
terminals). Researchers, PIs, Project Managers or Supervisors are encouraged to apply Hazard Class
B work rules / protection to such situations as a situation-specific hazard assessment may dictate.
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Page 49 of 96
UC Berkeley Electrical Safety Program
Attachment C: Qualification Training Requirements
[Excludes research apparatus / instruments (such as an electrophoresis power supplies or a High-Pot
Tester) that is approved by an NRTL as having safety-monitoring ground-fault circuit interruption built into
the control circuit of the equipment / apparatus.]
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Voltage / Amperage
Hazard Class
Training Required
Equal to or less than 50 Volts
And 5 milli-Amps or less.
A
Low-Hazard Operation
No Training Beyond
General Employee Training
Greater than 50 to 250 Volts
AC/DC and
greater than 5 milli-Amps
----------------------------------Per Hazard Assessment - DC
power 50 volts or less, but with
arc-flash potential of 5 mA – 1000
Amps available
B
Medium-Hazard
Operations
Greater than 250 to 600 Volts
AC/DC and
Greater than 5 milli-Amps.
------------------------------DC 50 Volts or less, but 1000 –
10,000 Amps available
C
Hazardous Operations
Electrical Utilization Training
EI/LOTO, First Aid and CPR
Renewed every year
Greater than 600 Volts
AC/DC
--------------------------------DC 50 Volts or less, but Greater
than 10,000 Amps available
D
High-Hazard
Operations
Electrical Utilization Training
High Voltage Training
EI/LOTO, First Aid and CPR
Renewed every year
Basic Electrical Safety Training
including the General Electrical Safework Rules
EI/LOTO Renewed every year
First Aid and CPR
Renewed every 3 years
NOTE: Continued qualification training includes an annual review of this program and all appendices
pertinent to the employee’s work assignment, electrical safe work program training pertinent to the
employee’s work assignment as required by the above table, and any other training(s) identified by the
employee’s Supervisor required for the safe performance of the employee’s duties. The Supervisor is
responsible for identification and assurance of the resources necessary for the completion of training
requirements for their individual direct reports. EHS ensures the necessary training is available through
internal training or the identification of qualified outside training providers.
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Page 50 of 96
UC Berkeley Electrical Safety Program
Attachment D1: Project Documentation Requirements
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Voltage / Amperage
Hazard Class
Documentation Required
Equal to or less than 50 Volts
And 5 milli-Amps or less.
A
Low-Hazard Operation
None
50 - 250 VAC/DC and
greater than 5 milli-Amps
B
Medium-Hazard
Operations
Hot Work Permit and
Generic Procedure
250 - 600 VAC/DC and
Greater than 5 milli-Amps.
C
Hazardous Operations
Hot Work Permit and
Shut Down Procedure
or
Switching Log
600 VAC/DC and Above
D
High-Hazard
Operations
Hot Work Permit and
Shut Down Procedure
or
Switching Log
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Page 51 of 96
UC Berkeley Electrical Safety Program
Attachment D2: Personnel Hot Work Qualification – Annual Record
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Document Qualifications and Annual Training for each “Qualified” person on this form.
U.C. BERKELEY
ANNUAL ELECTRICAL HOT WORK PERMIT
THIS PERMIT IS LIMITED TO 600v AND BELOW
FOR GENERAL RISK LEVEL 0-1 / <10 Calories DAILY ACTIVITIES AS DEFINED IN NFPA 70E:
COVER REMOVAL, GENERAL TESTING (VOLTS / AMPS), VISUAL INSPECTION, REPLACEMENT OF PLUG-IN
DEVICES, FUSES, BASE MOUNTED RELAYS, ATTACHMENT OF LOGGING AND SURVEY EQUIP. , AND SIMILIAR.
(ALL TASK ARE SUBJECT TO REVIEW AS DEEMED NECESSARY)
NAME:
EMP #:
DATE ISSUED:
VALID FOR ONE YEAR
FROM DATE OF ISSUE
EXPIRATION DATE:
AUTHORIZING PERSON / TITLE:
NOTES / COMMENTS:
THE INDIVIDUAL DESIGNATED ON THIS PERMIT IS RECOGNIZED AS FAMILIAR WITH POLICIES,
PROCEDURES, REQUIREMENTS AND APPLICATIONS PERTAINING TO
NFPA 70E ART. 110, WITH EMPHASIS ON ARTICLES 110.6(D) AND 110.7(G)
AND HAS BEEN DEEMED QUALIFIED AND AUTHORIZED TO PERFORM THE LISTED TASKS.
SPECIFIC ITEMS REVIEWED FOR ISSUANCE OF PERMIT
DISTINGUISH EXPOSED ENERGIZED PARTS
NOMINAL VOLTAGE (PHASE T0 PHASE)
NOMINAL VOLTAGE (PHASE T0 GRND)
NOMINAL APPROACH DISTANCES
CLEARANCE/WORK SPACE ASSESSMENT
HAZARD LEVEL ASSESSMENT
P.P.E. ASSESMENT
LADDERS AND EQUIPMENT
LIGHTING LEVELS ADEQUATE
COMMUNICATION DEVICES
CELL/RADIO SIGNAL STRENGHT
BACKUP/WATCH PERSON
BARRIER / SIGNAGE REQUIRED
TRAINING COMPLETED
INSULATED TOOL SET
PROPERLY RATED TEST EQUIP
SAFETY MATS
INSULATED GLOVES
HARD HAT / SHIELD
F.R. LONG SLEEVE SHIRT
F.R. PANTS
DATE
EMPLOYEE ORIENTATION
BASIC ELECTRICAL SAFETY
EI / LOTO
HIGH VOLTAGE
FIRST AID / CPR
OTHER: (LIST)
HEARING PROTECTION
SUPERVISOR'S SIGNATURE:
DATE:
EM PLOYEE'S SIGNATURE:
DATE:
REVIEW STAFF SIGNATURE:
DATE:
REVIEW STAFF SIGNATURE:
DATE:
REVIEW STAFF SIGNATURE:
DATE:
YOU ARE THE PERSON MOST RESPONSIBLE FOR YOUR SAFETY AND THE SAFETY OF OTHERS
DE-ENERGIZE EQUIPMENT WHENEVER POSSIBLE. ALWAYS DOUBLE-CHECK CIRCUITS ARE DEAD.
PLEASE FOLLOW ALL POLICIES AND PROCEDURES
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Page 52 of 96
UC Berkeley Electrical Safety Program
Attachment E: Shock Protection Boundaries
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All dimensions are distance from live part to personnel. Install construction cones and warning
tape to define the “Limited Approach Boundary” on the work site. Make all “Qualified and
Authorized” personnel on the job-site aware of the “Restricted Approach Boundary” distance for
the work being completed.
Nominal
System Voltage,
Phase to Phase
Limited
Approach
Boundary (movable
conductor)
Limited
Approach Boundary
(fixed conductor)
Restricted Approach
Boundary
Prohibited
Approach Boundary
<50
Not specified
Not specified
Not specified
Not specified
50 to 300
10 ft 0 in
3 ft 6 in
Avoid contact
Avoid contact
301 to 750
10 ft 0 in
3 ft 6 in
1 ft 0 in
0 ft 1 in
751 to 15kV
10 ft 0 in
5 ft 0 in
2 ft 2 in
0 ft 7 in
15.1 kV to 36 kV
10 ft 0 in
6 ft 0 in
2 ft 7 in
0 ft 10 in
36.1 kV to 46 kV
10 ft 0 in
8 ft 0 in
2 ft 9 in
1 ft 5 in
46.1 kV to 72.5 kV
10 ft 0 in
10 ft 0 in
3 ft 2 in
2 ft 1 in
72.6 kV to 121 kV
10 ft 8 in
10 ft 0 in
3 ft 3 in
2 ft 8 in
138 kV to 145 kV
11 ft 0 in
10 ft 0 in
3 ft 7 in
3 ft 1 in
INSTRUCTION NOTES ABOVE - From NFPA70E (2004) Table 130.2(C)
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Page 53 of 96
UC Berkeley Electrical Safety Program
Attachment F: Flash Protection Boundary
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For systems that are 600 volts or less, the Flash Protection Boundary shall be 4.0 feet based on the product
of clearing times of 6 cycles (0.1 second) and the available bolted fault current of 50 kA or any combination
not exceeding 300 kA cycles (5000 ampere seconds). For clearing times and bolted fault currents other than
300 cycles, or under engineering supervision, the Flash Protection Boundary shall alternatively be permitted
to be calculated in accordance with the following general formula:
Dc = [2.65 x MVAbf x t] 1/2
or
Dc = [53 x MVA x t] 1/2
Where:
Dc = distance in feet from an arc source for a second-degree burn
MVAbf = bolted fault capacity available at point involved (in mega volt – amps)
MVA = capacity rating of transformer (mega volt-amps). For transformers with MVA ratings below
0.75 MVA, multiply the transformer MVA rating by 1.25
t = time of arc exposure (in seconds)
At voltage levels above 600 volts, the Flash Protection Boundary is the distance at which the incident energy
equals 1.2 cal/cm2. For situations where fault clearing time is 0.1 second (or faster), the Flash Protection
Boundary is the distance at which the incident energy level equals 1.5 cal/cm2.
NOTES:
From NFPA70E (2004) Section 130.3(A).
In lieu of analyzing the Flash Protection Boundary, Table NFPA70E (2004) 130.7(C)(9)(a) may be
used.
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Page 54 of 96
UC Berkeley Electrical Safety Program
Attachment G: Protective Clothing Characteristics
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Unless actual arc-flash calculations are completed according to the most recent NFPA 70E
Electrical Safety Code, and the available arc-flash energy is known for the work location is used to
determine specific PPE and tools needed to work safely, either select PPE and tools per NFPA 70E
Section 130.7, or select PPE and tools for the higher Hazard Class noted below.
NFPA70e
Hazard Risk
Category (Number)
or
Hazard Class
(Voltage
AC or DC)
0
A
1
A and/or B
2
B and/or C
3
C and/or D
4
D
Clothing System
Description
(No. of Layers)
Cotton Fabric
Total
Weight
(oz/yd2)
Minimum Arc
Rating
ATPV or EBT
cal/cm2
Untreated Cotton (1)
4.5 - 7
N/A
FR Shirt and FR Pants (1)
Use insulated tools.
Cotton Underwear plus
FR Shirt and FR Pants (2)
Use insulated gloves and tools
Cotton Underwear plus
FR Shirt and FR Pants plus FR Coverall (3)
Use voltage-rated insulated gloves and tools.
Cotton Underwear plus
FR Shirt and FR Pants plus
Double layer Switching Coat (4)
Use voltage-rated insulated gloves and tools.
4.5 - 8
4
9 - 12
8
16 - 20
25
24 - 30
40
Special Tools / PPE
NOTES: Hazard Risk Category (Number) from NFPA70E (2004) Tables 130.7 (C)(9)(a) and
130.7(C)(11)
Hazard Class (letter) is a simple way to determine approximate hazard based upon available
voltage of the exposed conductor being worked on. Hazard Risk Category (number) is based upon
the available arc-flash amperes for approximately 6-cycles AC prior to circuit interrupters being
tripped.
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Page 55 of 96
UC Berkeley Electrical Safety Program
Attachment H: Shut Down Request Form
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Page 56 of 96
UC Berkeley Electrical Safety Program
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Page 57 of 96
UC Berkeley Electrical Safety Program
Attachment I: Electrical Hot Work Permit
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Document approval for each Hot Work Permit situation on this form. Maintain in project file as
permanent record.
U.C. BERKELEY
revised 8/4/2010
ELECTRICAL HOT WORK PERMIT
FOR DIRECT CONTACT WITH 600v AND BELOW ENERGIZED PARTS ONLY, i.e.:
BREAKER REPLACEMENT, BUSS MODIFICATION, HOT TAP, RACKING OUT / IN,
OR AS DEEMED NECESSARY.
THIS PERMIT IS REQUIRED FOR TESTING ABOVE 600 v.
BUILDING:
PNL:
DATE SUBMITTED:
WORK DATE:
CRAFTSPERSON:
LOCATION:
FROM / TO:
AM/PM
AM/PM
ASSISTANT (REQ'D):
W.O. #:
BUILDING CONTACT PERSONS:
DESCRIPTION OF WORK TO BE PERFORMED:
JUSTIFICATION FOR WORKING ENERGIZED EQUIPMENT:
JOB HAZARD ASSESSMENT
NOMINAL VOLTAGE (PHASE T0 GRND)
Use References From
NFPA 70E TABLES
NOMINAL VOLTAGE (PHASE T0 PHASE)
130.7(C)(9)(A);
CLEARANCE / WORK SPACE (FT. / IN.)
and U.C.B.Electrical Safety Program
RESTICTED or PUBLIC WORK AREA?
130.7©(11);
CALORIE CALCUALTIONS
130.2(C)
Risk Level
BARRIER / SIGNAGE REQUIRED?
LIGHTING LEVELS ADEQUATE?
RADIO / CELL SIGNAL STRENGHT (0-10)
APPROACH BOUNDARIES
DISTANCE
LIMITED
RESTRICTED
PROHIBITED
FINAL ASSESSED RISK FACTOR - (0 - 4) :
Cm2 LEVEL PPE CLOTHING:
SAFETY EQUIPMENT CHECK LIST
SAFETY EQUIPMENT
Y / N / N.A.
MATERIAL/EQUIP.
INSULATED TOOL SET
HEARING PROTECTION
RATED TEST EQUIPMENT
SAFETY MAT
INSULATED GLOVES
LIGHTING
HARD HAT / SHIELD (10 Cm2)
FIBERGLASS LADDER
LONG SLEEVE SHIRT (10 Cm2)
GROUNDING CABLES
PANTS (10 CAL)
OTHER
Y / N / N.A.
TWO LAYER (+10Cm2 / - 40Cm2)
40 CAL SUIT / HOOD (+10 Cm2)
100 CAL SUIT / HOOD (+40 Cm2)
SUPERVISOR'S SIGNATURE:
DATE:
EMPLOYEE'S SIGNATURE:
DATE:
EMPLOYEE'S SIGNATURE:
DATE:
EMERGENCY PHONE NUMBERS:
U.C.P.D. - 642-6760
TANG CENTER: 642-2000
YOU ARE THE PERSON MOST RESPONSIBLE FOR YOUR SAFETY AND THE SAFETY OF OTHERS
PLEASE FOLLOW ALL POLICIES AND PROCEDURES
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UC Berkeley Electrical Safety Program
Attachment J: Switching Log Form
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UC BERKELEY SWITCHING LOG
Page __ of __
Planned Operations Date:
Purpose:
STEP LOCATION OPERATION DEVICE
INSTRUCTIONS
PREPARED BY / DATE:
SCADA CHECK:
TIME
HV CHECK:
ENG. CHECK:
COMP.
BY:
DATE:
Page 59 of 96
UC Berkeley Electrical Safety Program
Definitions:
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Arc Rating (of Clothing / PPE) - The maximum incident energy resistance demonstrated by a PPE material (or
a layered system of PPE materials) prior to break open or at the onset of a second-degree skin burn. Arc
rating is normally expressed in calories per centimeter squared (cal/cm2).
Break open - Is an insulating PPE material response evidenced by the formation of one or more holes in the
innermost layer of a flame-resistant material that would allow flame to pass through the material to the skin
underneath.
Flash Hazard Analysis - A study investigating a worker’s potential exposure to arc-flash energy, conducted
for the purpose of injury prevention and the determination of safe work practices with the appropriate levels
of personal protective equipment (PPE).
Flash Protection Boundary - An approach limit at a distance from exposed live parts within which a person
could receive a second degree burn if an electrical arc flash were to occur.
Incident Energy - The amount of energy impressed on a surface, a certain distance from the source,
generated during an electrical arc event. One of the units used to measure incident energy is calories per
centimeter squared (cal/cm2).
Prohibited Approach Boundary - A distance from an exposed live part within which work is considered the
same as making contact with the live part. All of the requirements for limited and restricted boundaries
apply. Any work inside the prohibited boundary is considered the same as being in contact with the exposed
uninsulated conductor. No electrically uninsulated part of the body may cross the prohibited approach
boundary.
Restricted Approach Boundary - A distance from an exposed live part within which there is risk of shock due
to electrical arc-over combined with inadvertent movement by persons working in close proximity to the live
part. Only qualified and authorized electrical workers are allowed inside the Restricted Approach Boundary.
As the worker is now working near the exposed hazard, all required PPE appropriate to the shock hazard
must be worn. The worker must have an approved plan for the work they are to perform. They may cross the
restricted boundary only to the extent that is necessary to perform their work.
Shock Hazard Analysis - Determination of the voltage to which personnel will be exposed, boundary
requirements and the personal protective equipment necessary in order to minimize the possibility of
electric shock to personnel.
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Page 60 of 96
UC Berkeley Electrical Safety Program
Attachment K: Electrical Equipment Safe Work Space Requirements
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Go to “How this program applies to you”.
Sufficient space is provided and maintained about electrical equipment to permit ready and safe
operation and maintenance. Where energized parts are exposed, the minimum clear work space is
never less than 6 ½ ft high (measured vertically from the floor) or less than 3 ft wide (measured
parallel to the equipment). The depth is shown in the following table and in all cases the work space
will permit at least a 90 degree opening of doors or hinged panels.
Nominal Voltage
to Ground
Condition 1
Condition 2
Condition 3
601-2500 V
3 ft
4 ft
5 ft
2501 -9000 V
4 ft
5 ft
6 ft
9001 -25,000 V
5 ft
6 ft
9 ft
25,001 V – 75 kV
6 ft
8 ft
10 ft
Above 75 kV
8 ft
10 ft
12 ft
Condition 1 – exposed live parts on one side of the working space and no live or grounded
parts on the other side of the working space, or exposed parts on both sides of the
working space that are effectively guarded by insulating materials.
Condition 2 – exposed live parts on one side of the working space and grounded parts on
the other side of the working space. Concrete, brick, or tile walls are considered as
grounded.
Condition 3 – exposed live parts on both sides of the working space.
NOTES:
From the California Electrical Code (CEC2007), section 110.32.
Page 61 of 96
UC Berkeley Electrical Safety Program
Attachment L: Research Equipment Fabrication and Maintenance
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 Design and construct equipment to protect personnel.
 First-line and backup safeguards should be provided to prevent personnel from accessing
energized circuits.
 Establish periodic tests to verify that these protective systems are operative.
Designs




Have designs reviewed: All systems and modifications to systems performing a safety
function or controlling a potentially hazardous operation must be reviewed and approved at
the level of project engineer or EH&S campus Safety Engineer.
Have designs and operation verified: All systems performing safety functions or controlling a
potentially hazardous operation must be validated by actual test procedures before being
placed in service, at least once a year, and anytime the system is suspected of malfunction.
Both the procedures and actual tests must be documented.
The Department responsible for the equipment must maintain all documentation pertaining
to the design safety features of the equipment, including any test data. This documentation
must be available at any time to any safety inspector or EH&S Safety Engineer.
Whenever possible, purchase NRTL approved equipment to conduct research instead of
building your own. This equipment will be designed, tested and manufactured to generally
assure safe work activities, and in most cases is designed to fail safe.
Equipment Acceptability
Electrical equipment is considered safe only when it is used as specifically intended by its listing and
design. Equipment listed by an NRTL must not be altered beyond the original design intent, and must
not be used for any purpose other than that for which it was constructed. If equipment must be
altered beyond the original design intent, please contact EH&S Safety Engineer to discuss hazard
potential and hazard control options.
Any equipment that is being re-commissioned must be examined and/or tested, as appropriate, to
verify the status of all safety features and the integrity of construction.
 Electrical equipment, and electrical components used in experimental apparatus, should be
listed or labeled by an NRTL.
 EH&S may require that equipment that is not NRTL-listed undergo inspection and/or testing
for conformance to standards. Such testing should be documented and submitted to EH&S
for approval. The inspection record must specify, at minimum:
 Equipment identification;
 Evaluator name, date, mailstop, and extension;
 Standard to which equipment is being evaluated;
 Specific tests, results, and areas of examination;
 Any conditions of product acceptability or limitations of use.
 Inspection records are kept at the site of the apparatus with copies in the experimental
records.
Page 62 of 96
UC Berkeley Electrical Safety Program
Equipment Safety Practices











Cable Clamping: A suitable mechanical-strain-relief device such as a cord grip, cable clamp,
or plug must be used for any wire or cable penetrating an enclosure where external
movement or force can exert stress on the internal connection.
Isolation: Isolate all sources of dangerous voltage and current with covers and enclosures.
Access to lethal circuits (greater than 50V) must be either via screw-on panels (each
containing no fewer than four screws or bolts) or via interlocked doors, panels, covers, etc.
The frame or chassis of the conductive enclosure must be bonded to electrical ground with a
conductor capable of handling any potential fault current. Access panels, doors, etc. that
could allow contact with energizes conductors should be interlocked with control circuits to
de-energize electrical conductors if panel doors are opened / removed.
Lighting: Provide adequate lighting for easy visual inspection.
Disconnecting Means and Overload Protection: Provide overload protection and well-marked
disconnects. Local “off” controls must be provided on remote-controlled equipment.
Disconnects and breakers must be clearly labeled to identify the loads they control.
Power: All ac and dc power cabling to equipment not having a separate external ground but
having line-to-line or line-to-ground voltage greater than 50V must have an equipmentgrounding conductor unless cabling is inside an interlocked enclosure, rack, grounded wire
way, or conduit, or feeds a commercial double-insulated or UL-listed ungrounded device. If
the grounding of equipment introduces a greater hazard, the equipment must not be
grounded.
Rating: Operate all conductors, switches, resistors, etc., within their design capabilities.
Pulsed equipment must not exceed the average, the rms, or the peak rating of components.
The equipment must be de-rated as necessary for the environment and the application of the
components.
Safety Grounding of Capacitive Components: Use automatic-discharge devices on equipment
with stored energy of 100J or more. Suitable and visible manual-grounding devices must also
be provided to short-to-ground all dangerous equipment while work is being performed.
Electrical Equipment Rooms: Place an identifying label or sign on the door when equipment
that may require servicing, manipulation, or inspection is concealed in an equipment closet
or otherwise is obscured behind doors or panels.
Reuse of Circuit Breakers: Do not purchase used or reconditioned circuit breakers from
vendors outside UCB. Reuse of UCB circuit breakers is permitted only after the circuit
breaker has been tested by the UCB Electric Shop.
Only use circuit breakers designed to be installed in specific distribution boxes per
manufacturer model number.
Enclosures
The following specifications apply to circuits operating at greater than 50V, or storing more than
100J. An enclosure may be a room, a barricaded area, Faraday cage or an equipment cabinet:
 Access: Interlock easily opened doors, hinged panels, etc., that allow ready access to
exposed energized components so that the act of opening de-energizes the circuit. Automatic
discharge of stored-energy devices must be provided.
 Doors: Doors should be key-locked, and the same key should also be used for the locks in
the control-circuit interlock chain, if applicable. This key must not be able to be removed from
the door unless the door is closed and locked.
 Heat: Mount heat-generating components, such as resistors, so that heat is safely dissipated
and does not affect adjacent components.
Page 63 of 96
UC Berkeley Electrical Safety Program





Isolation: Ensure that the enclosure physically prevents contact with live circuits. The
enclosure can be constructed of conductive or nonconductive material. If conductive, the
material must be electrically bonded and connected to a good electrical ground. These
connections must be adequate to carry all potential fault currents.
Seismic Safety: Secure all racks, cabinets, chassis, and auxiliary equipment against
movement during earthquakes.
Strength: Ensure that enclosures are strong enough to contain flying debris caused by
component failure.
Ventilation: Ensure that ventilation is adequate to prevent overheated equipment, and to
purge toxic fumes produced by an equipment fault. Ventilation openings must not be
obstructed.
Visibility: Ensure that enclosures large enough to be occupied by personnel allow exterior
observation of equipment and personnel working inside the enclosure.
Cord and Plug Equipment (Testing and Maintenance)
An unqualified worker may remove covers and work on electrical equipment that has stored energy
below 1000 joules and which is powered only through a 120 Volt Line-Cord that can be unplugged
and positively controlled.
When electrical equipment has stored energy above 1000 joules and is only powered through a 120
Volt Line-Cord that can be unplugged and positively controlled then a qualified worker, wearing the
PPE listed below must verify that all stored energy in the chassis has dissipated. Once the electrical
safe condition is verified requirements for PPE and worker qualification are no longer in effect until
the chassis is reenergized.
PPE requirements for verifying the safe state of 120 Volt cord and plug equipment:
 Natural fiber long-sleeve shirt
 Natural Fiber long pants
 Natural Fiber Undergarments
 Non-conductive safety glasses
 Voltage rated gloves and leather protectors
 Voltage rated tools
 Category III or IV Multi-meter
 Supervisor briefing or written procedure task specific to the equipment
Page 64 of 96
UC Berkeley Electrical Safety Program
Attachment M: Practices for Heating Tapes and Cords
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Go to Table of Contents
Go to “How this program applies to you”.
Many experiments at UCB use heating tapes or cords, including many high vacuum apparatus. The
heating tapes or cords pose an electrical shock hazard if not used properly. This section establishes
requirements for the proper selection, care, and use of heating tapes and cords. These guidelines
also apply to heating pads, wraps, or similar components intended to be applied directly to
laboratory apparatus. Exemptions to the below requirements must be approved by the EH&S Safety
Engineer.
General Electrical Safety Requirements for Use of Heating Tape
 Read all of the manufacturer’s instructions before using any heating device.
 Whenever possible, use heating tapes that bear a Listing mark by an NRTL.
 Use three-wire (grounded) heating tape and cord systems whenever practical. Two-wire heat
tapes and cords, while allowed for use at UCB, are inherently less safe than three-wire
systems.
 Inspect heating tapes and cords before use and discard any that display signs of excessive
wear, fraying, or overheating. Do not repair damaged items.
 Properly ground all conductive equipment surfaces before heating tapes are powered.
 Equipment undergoing heating with a variable AC transformer controlled heat tape must be
monitored on a regular basis to prevent overheating of either the chamber or the heating
device.
 Heating tapes and cords with an AC plug that can be split into two pieces must have the plug
replaced or glued together.
 Use heat tapes only on surfaces for which they are designed. Glas-Col® heating cords are an
example of a cord that may NOT be used at UCB for any purpose other than heating
glassware and non-metallic apparatus.
 If you are unsure whether or not your heating tape or cord is approved for use at UCB,
contact the EH&S Safety Engineer.
Heating Tape Power Source Requirements
 A Ground Fault Current Interrupter (GFCI) protected power source must be used. Portable
GFCI adaptors are acceptable. Before use, the GFCI must be tested: depress the “TEST”
button, verify that the “RESET” button pops out, and then depress the “RESET” button.
 A maximum of 1920 Watts of heating capacity may be placed on a 20-amp circuit breaker.
 A maximum of 1440 Watts heating capacity may be placed on any individual power cord,
receptacle, or relocatable power tap (power strip).
Circuit Breaker Trip
If a circuit breaker trips during a heating operation, this is usually because the circuit is overloaded.
Disconnect an appropriate number of the heat tapes and reset the breaker. If the breaker trips
again, call an UCB qualified electrical worker or EH&S Safety Engineer for help.
GFCI Trip
If a GFCI trips during the heating operation, it is permissible to reset the GFCI one time. Personnel
must remain clear of equipment when the GFCI is reset. If the GFCI trips again, all of the heating
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UC Berkeley Electrical Safety Program
tapes must be disconnected and thoroughly inspected for damage. If the problem persists, call a
UCB qualified electrical worker or EH&S Safety Engineer.
Variable Transformer Issues
If the fuse blows in the device, replace the blown fuse only with a fuse rated for the device. Using a
higher current fuse than rated for the device will allow overheating and may cause a fire. Variable
transformers and other control devices for heat tape control should be periodically checked by a
qualified electrical worker for receptacle tension and proper fusing.
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UC Berkeley Electrical Safety Program
Attachment N: Practices for Flexible Cords
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
Because cord and plug connections are generally well understood, this instruction does not cover
portable hand-operated power tools, small kitchen appliances, office equipment, electronic
instruments, personal computers, and other similar equipment.
Flexible cords and cables may be used for:
 Pendants.
 Wiring of fixtures.
 Connections of portable lamps or appliances.
 Elevator cables.
 Crane and hoist wiring.
 Connecting stationary equipment that requires frequent interchange.
 Preventing transmission of noise or vibration.
 An appliance or equipment with fastenings and mechanical connections specifically designed
to permit removal for maintenance and repair, and intended or identified for flexible cord
connection.
 Power cables (ac) for data-processing equipment.
 Connecting moving parts.
When flexible cords and cables are used for lamps or appliances they must be equipped with an
approved attachment plug and energized from a receptacle outlet. Only qualified persons may install
cord caps, (the attachment plug), on cords.
Flexible cord and cable, attachment plugs, and receptacles must be of the proper type, size, and
voltage and current rating for the intended application.
Branch circuits that feed cord-and-plug connected equipment must be designed, have over current
protection and be grounded in accordance with the CEC.
All cord-and plug-connected equipment must be grounded with a correctly sized and identified
equipment-grounding conductor that is an integral part of the ac power cord or cable. Exception:
Listed equipment that is protected by a double insulation system or its equivalent.
It is UCB policy to allow cord and plug connection of equipment that operates at 250V or less and
has a maximum circuit rating of 30 A. Any equipment operating at higher voltages or currents should
be permanently connected. (Exception; portable arc welders)
Forbidden Uses of Flexible Cables:
 Substituted for the fixed wiring of a structure.
 Run through holes in walls, ceilings, or floors.
 Run through doorways, windows, or similar openings.
 Attached to building surfaces.
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UC Berkeley Electrical Safety Program


Concealed behind building walls, ceilings, or floors.
Installed in electrical raceways, unless specifically allowed by CEC provisions covering
electrical raceways.
Except for the temporary wiring provisions of CEC, the CEC does not allow the cord-and-plug
connection of equipment to be energized from extension cords. Extension cords are not legitimate
substitutes for the fixed wiring of a structure such as a receptacle outlet.
In industrial locations, such as shops, a suitable guard or cover must protect the interface between
attachment plug and receptacle from intrusion of process waste or other foreign material, such as
cutting oils and machining chips.
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UC Berkeley Electrical Safety Program
Attachment O: Use of Extension Cords
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
Extension cords provide a convenient method of bringing AC power to a device that is not located
near a power source. They are used as temporary power sources. Extension cords are probably
involved in more electrical-code and safety violations than any other device at UCB. They are stepped
on, tripped over, stretched, cut, overloaded, and, in general, used improperly.
Guidelines for the Safe Use of Extension Cords:
 Use only approved and properly maintained extension cords that have no exposed live parts,
exposed ungrounded metal parts, damage, or splices.
 Use only heavy-duty or extra-heavy-duty rated cable.
 Use extension cords that are protected by a ground fault circuit interrupter (GFCI) around
construction sites, in damp areas, or in an area where a person may be in direct contact with
a solidly grounded conductive object (e.g., working in a vacuum tank). The GFCI can consist
of a special circuit breaker, a GFCI outlet, or an extension cord with a built-in GFCI.
 Ensure that the extension cord is of sufficient current-carrying capacity to power the device.
Use of an undersized cord results in an overheated cord and insufficient voltage delivered to
the device, thus causing device or cord failure and a fire hazard. Undersized cords also
constitute a serious shock hazard as it may not allow the breaker feeding it to trip.
 Always use three-conductor (grounded) extension cords—even if the device has a twoconductor cord. Never use two-conductor extension cords at the Laboratory.
 Extension cords are for temporary use: In general, roll-up the cord at the end of the day. If
an extension cord is required for the same work at the same location on a continual basis,
you should call Facilities to install an additional receptacle where you actually need the
power, or move the equipment. Do not daisy-chain extension cords. Check the cord for
damage each time you use it. Electricians can repair damaged cords.
 If extension cords cross foot-traffic aisles, use cord protectors of a bright color, preferably
orange or yellow, to highlight the cord and protect it against impact. For very temporary
installations, use brightly colored duct tape to tape the cord to the floor making sure the cord
is straight without kinks or loops.
 If extension cords cross vehicle traffic aisles or roadways, use cord protectors strong enough
to prevent vehicle contact with the cord.
Avoiding Misuse of Extension Cords:
Observe the following restrictions to avoid misuse of extension cords.
 Do not use extension cords in place of permanent facility wiring.
 Avoid running extension cords through doors, ceilings, windows, or holes in the walls. If it is
necessary to run a cord through a doorway for short term use, ensure that the cord is:
o Protected from damage.
o Removed immediately when no longer in use.
o Not a tripping hazard.
 Tape the cord down to the floor using a brightly colored (orange or yellow) duct tape.
 Do not daisy chain extension cords (i.e., plug one extension cord into another extension
cord).
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UC Berkeley Electrical Safety Program



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Do not overload extension cords. Make sure that the wire size is sufficient for the current
required.
Do not cut off the ground pin of an extension cord or compromise the ground protection in
any way.
Do not use extension cords with a ground conductor that has less current-carrying capacity
than the other conductors.
Do not use frayed or damaged extension cords.
Never splice extension cords, even for a repair. If an extension cord is damaged, it may be
made into two cords, provided the proper connectors are used in a proper manner. Only
qualified personnel may install cord caps for use with potentials greater than 50V.
Only qualified personnel may make repairs of extension cords.
Acceptable Combination (for Office Only)
One single extension cord (single outlet) to a power strip (with over current protection) to a computer
system is not recommended, but will be accepted to provide power to personal computer systems
and peripherals only when there is no other reasonable way to do so. This is an interim solution,
limited to 600 watts total load. For long-term installation a premises wiring outlet at the computer
system will be required.
Relocatable Power Strips / Power Taps (for Office and Lab Bench Tops Only)
A relocatable power tap (also referred to as a “Power Strip”) is a variation of an extension cord,
where the cord terminates in a row or grouping of receptacles. Relocatable power taps are commonly
used in offices to provide multiple receptacles to office equipment. In general, all rules pertaining to
extension cords also apply to relocatable power taps.
Additional considerations are:
 Relocatable power taps are not rated for heaters, refrigerators, toaster ovens, or other high
power devices. They may be used only for office equipment such as computers, printers, etc.
 The total load on the relocatable power tap must not exceed 1440 watts or 12 amperes. Any
single load (single receptacle) must not exceed 600 watts (5 amperes).
 Do not permanently mount relocatable power taps to any facility surface.
 Relocatable power taps are classified as temporary devices. It is acceptable to hang them
from screws or hooks if they are manufactured with slots or keyholes.
 In equipment racks, the preferred method of supplying 120/208V utility power to rackmounted instruments is via a special relocatable power tap specifically designed to be rackinstalled.
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UC Berkeley Electrical Safety Program
Attachment P: Practices for Portable Workbenches
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
This section covers laboratory and shop workbenches that can be moved by sliding, rolling, etc. It
does not cover built-in workbench assemblies that are permanently attached to structure surfaces.
Such built-in assemblies must use appropriate fixed-wiring methods to provide power for
receptacles, lighting fixtures, ventilation fans, etc., in accordance with the CEC.
Flexible cord and plug assemblies may be used to provide ac power to portable workbenches only
when:
 The branch circuit voltage supplying the workbench is 150V or less.
 The over current protection device rating on the branch circuit supplying the workbench is
20A or less.
 The flexible cord is no longer than 4.5 m (15 ft), is attached to the workbench with an
approved tapered rubber-bushing cord-grip fitting, is no smaller than #14 AWG, is type-listed
under the CEC as “Extra Hard Usage” (Type SO, G, W, etc.), is protected from physical
damage, is routed to prevent tripping hazards, and is terminated in a listed attachment plug
and mating receptacle interface that has the proper voltage and current rating for the branch
circuit feeding the workbench.
 Each workbench has its own cord, attachment plug, and branch circuit receptacle.
Workbenches must not be parallel fed or daisy chained by plugging their power cords into a
receptacle located on another workbench.
 Each workbench wiring system has equipment-grounding protection that consists of a
correctly sized and identified equipment-grounding conductor. This grounding conductor
must be an integral part of the flexible cord. Grounding circuit continuity must be provided by
the branch circuit wiring feeding the workbench, and at the interface between attachment
plug and receptacle.
 All metal surfaces of the workbench assembly that are likely to become energized by an
electrical fault are properly bonded to the equipment grounding conductor in accordance
with the CEC.
 The number of workbench receptacle outlets is limited to no more than 10 duplex
receptacles or 3 linear meters (10 linear ft) of wire-mold plug strip on a 15A branch circuit, or
13 duplex receptacles or 4 linear meters (13 linear ft) of an approved multi-outlet assembly
on a 20A branch circuit. In any case, the continuous load fed by the workbench outlet
receptacles must not exceed 80% of the rating of the branch circuit that feeds the
workbench.
 Each workbench has proper seismic anchoring or other restraint against unintentional
movement so that the cord-and-plug AC input power assembly is protected from damage
resulting from tension, pinching, crushing, etc.
 If the bench is fitted with a metallic or otherwise conductive work surface, the workbench
wiring system is protected by an approved GFCI.
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UC Berkeley Electrical Safety Program
Attachment Q: Practices for Power Supplies
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
Primary Disconnect
Provide a lockable means of positively disconnecting the input on large power supplies. This
disconnect must be clearly marked and accessible.
If provided with a built-in lock that is part of an interlock chain, the key must not be removable
unless the switch or breaker is in the “off” position.
Overload Protection
Overload protection must be provided on the input and should be provided on the output.
Floating Power Supplies
Some research equipment (e.g., electrophoresis devices, x-ray tubes, and ion-bombardment power
supplies) employ ungrounded (floating) power supplies. This equipment may operate in voltages
ranging from 50V to kilovolts, with output capacities in excess of 50mA, and must be considered a
lethal electrical hazard. Users of such equipment must take special precautions to minimize
electrical hazards. Follow all manufacturers’ instructions for equipment use, testing, and training.
The following general guidelines also apply:
 Locate equipment away from water and large metal areas.
 Do not use connectors and jack fittings that allow accidental skin contact with energized
parts.
 Interlock readily accessible enclosures.
 Use nonmetallic secondary containment if liquids or gels are involved.
 Verify that the power supply is floating when commissioning and recommissioning the
equipment and at least once a year.
Power supplies used in Human Subjects Experiments
All research involving power supplies that supply power to research apparatus / equipment
intimately in contact with human subjects must have fail-safe monitoring of output power circuits.
Such power supplies must be able to detect any ground fault or phase-to-phase fault on the output
of the power supply and immediately (within three-cycles) shut-down the output of the power supply
to the research apparatus. Such power supplies must be manufactured, tested and approved by an
NRTL to be ‘fail safe’ for use on Human Subjects Experiments. In addition, a second level of safety is
required to physically isolate the Human Subject from any potential electrical hazard through use of
dielectric shielding or containment of the research apparatus. Dielectric shielding must be reviewed
and approved by an NRTL or a licensed Professional Engineer with expertise in the field of study prior
to proceeding with Human Subject Experiments involving electrical apparatus. Also, when power
supplies are attached to building power, it’s a good idea to power them using GFCI-protected power
circuits.
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UC Berkeley Electrical Safety Program
Attachment R: Practices for Capacitor Hazards
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
This section describes some key practices for both high and low voltage capacitors. For further
details the CEC and CalOSHA should be consulted.
Low voltage (<600v) capacitor safety practices:



Capacitors containing more than 3 gallons of flammable liquid are enclosed in vaults or outdoor
fenced enclosures.
Capacitors are enclosed, located, or guarded so that persons cannot come into accidental
contact or bring conducting materials into accidental contact with exposed energized parts,
terminals, or buses associated with them.
Capacitors are provided with a disconnecting and automatic means of draining the stored charge
to 50 volts or less within one minute after the capacitor is disconnected from the source of
supply.
High voltage (>600v) capacitor safety practices:







Capacitors shall be provided with a permanent nameplate giving the makers name, rated
voltage, frequency, kvar or amperes, number of phases, and the amount of liquid identified as
flammable, if such is the case.
Capacitors containing more than 3 gallons of flammable liquid are enclosed in vaults or outdoor
fenced enclosures.
Capacitors are enclosed, located, or guarded so that persons cannot come into accidental
contact or bring conducting materials into accidental contact with exposed energized parts,
terminals, or buses associated with them.
Capacitors are provided with a disconnecting and automatic means of draining the stored charge
to 50 volts or less within five minutes after the capacitor is disconnected from the source of
supply.
A means shall be provided to detect and interrupt fault current liable to cause dangerous
pressure within an individual capacitor.
Single pole individually operated or multiple pole group operated switches used for capacitor
switching shall be capable of carrying continuously not less than 135 percent of the rated
current of the capacitor installation.
Care shall be exercised in handling and disposing of failed capacitors because of possible
internal pressure and residual energy.
Storing capacitors - safety practices:


Capacitors shall be stored with permanent grounding straps attached to the capacitor terminals
to prevent electrical charge build-up during storage.
If you find an old capacitor that has been in storage but does not have grounding strap attached
to its terminals, do not touch the capacitor or try and ground it yourself. Contact the EH&S Safety
Engineer or the PP-CS Electrical Engineer immediately to determine next steps.
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UC Berkeley Electrical Safety Program
Attachment S: Practices for Inductor and Magnet Hazards
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
This section describes some hazards peculiar to inductors and magnets that can store more than
100J of energy or that operate at 50V or more. For further details the CEC and CalOSHA should be
consulted, but consider that inductors and magnet hazards include:
 The ability of an inductor to release stored energy at a much higher voltage than used to
charge it.
 Stray magnetic fields that attract magnetic materials.
 Time-varying stray fields that induce eddy currents in conductive material, thereby causing
heating and mechanical stress.
 Time-varying magnetic fields that may induce unwanted voltages at inductor or magnet
terminals.
Safety Practices:







Energy Control. Know and use the UCB EI/LOTO program and policies.
Automatic Discharge. Use freewheeling diodes, varistors, thyrites, or other automatic shorting
devices to provide a current path when excitation is interrupted.
Connections. Pay particular attention to connections in the current path of inductive circuits.
Poor connections may cause destructive arcing.
Cooling. Many inductors and magnets are liquid-cooled. The unit should be protected by
thermal interlocks on the outlet of each parallel coolant path, and a flow interlock should be
included for each device.
Eddy Currents. Units with pulsed or varying fields must have a minimum of eddy-current
circuits. If large eddy-current circuits are unavoidable, they should be mechanically secure
and able to safely dissipate any heat produced.
Grounding. Ground the frames and cores of magnets, transformers, and inductors.
Rotating Electrical Machinery. Beware of the hazards of residual voltages that exist until
rotating electrical equipment comes to a full stop. If needed block rotating electrical
machinery so that mechanical rotation cannot occur prior to working on it.
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UC Berkeley Electrical Safety Program
Attachment T: Practices for Control and Instrumentation Design
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
Proper philosophy is vital to the safe design of most control applications. The following checklist
should be used as a guide.
 Checkout. Check interlocks for proper operation after installation, after any modification, and
during periodic routine testing. Document interlock tests in the experimental log book at
least annually, whenever the apparatus has an unexpected event, or when the interlock
system is modified.
 Fail-safe design. Design all control circuits to be “fail-safe.” Starting with a breaker or fuse,
the circuit should go through all the interlocks in series to momentary on-off switches that
energize and “seal in” a control relay. Any open circuit or short circuit will de-energize the
control circuit and must be reset by overt act.
 Interlock Bypass Safeguards. Establish a systematic procedure for temporarily bypassing
interlocks. Follow-up procedure should be included to ensure removal of the bypass as soon
as possible. When many control-circuit points are available at one location, the bypassing
should be made through the normally open contacts of relays provided for this purpose. In an
emergency, these relays can be opened from a remote control area.
 Isolation. Isolate control power from higher-power circuits by transformers, contactors, or
other means. Control power should be not more than 120V, ac or dc. All circuits should use
the same phase or polarity so that no hazardous additive voltages are present between
control circuits or in any interconnect system. Control-circuit currents should not exceed 5A.
 Lockout. Use a keyed switch in interlock chains to provide positive control of circuit use. To
ensure power removal before anyone enters the enclosure, this same key should also be
used to gain access to the controlled equipment.
 Motor Control Circuits. Motor circuits must have a positive disconnect within view of the
motor or, if this is not practical, a disconnect that can be locked open by the person working
on these motor circuits.
 Overvoltage Protection. Control and instrumentation circuits used with high-voltage
equipment must have provision for shorting fault-induced high voltages to ground. Highvoltage fuses with a high-current, low-voltage spark gap downstream from the high-voltage
source are recommended. This also applies to all circuits penetrating high-voltage
enclosures.
 Voltage Divider Protection. The output of voltage dividers used with high voltages must be
protected from overvoltage-to-ground within the high-voltage area by spark gaps, neon bulbs,
or other appropriate means.
 Current Monitors. Measure currents with a shunt that has one side grounded, or with current
transformers that must be either loaded or shorted at all times.
 Instrument Accuracy. Check instrumentation for function and calibration on a routine basis.
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UC Berkeley Electrical Safety Program
Attachment U: Practices for Ground Fault Circuit Interrupters (GFCIs)
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
GFCI’s are designed to protect a person from electric shock when he or she simultaneously contacts
a “live” (usually 120V) wire or part and a grounded object. The GFCI works by sensing a difference
between the supply and return currents. When the difference exceeds 5mA—indicating that current is
flowing to ground (through the person)—the device switches off.
Although the GFCI is an effective safety device, it is not a guarantee against shock in every situation.
The GFCI does not protect against a line-to-neutral or a line-to-line shock. Also, if GFCI-protected
equipment contains transformers, a ground fault (shock) on the secondary side of the transformer
may not trip the GFCI.
GFCI’s are normally installed as either circuit breakers or receptacles. In either case, the GFCI may
be wired to protect multiple receptacles. Individual GFCI plug-in adapters are also available.
UCB requires GFCI protection for the following conditions:
1. Any 120V convenience outlet located within 2 m (6 ft) of an open water source. This does not
include emergency eyewash showers or fire sprinklers.
2. Any 120V convenience outlet located outdoors.
3. Any 120V convenience outlet located within 2 m (6 ft) of a “massive ground.” (A massive
ground is a large area of metal, wet earth, metallic utility piping, or other highly conductive
surface that enhances the conductivity to ground of the person touching it.)
4. Any extension cord providing power for construction activities.
5. Any resistance heating equipment not having a metal covering, such as heating tapes.
6. When supplying power to experiments with “Human Subjects”.
It is UCB policy to implement the GFCI requirements in conditions 1, 2, and 3 above on a phase-in
basis. Any new or remodel construction will include the GFCI’s as specified. Existing locations should
be prioritized for retrofitting according to relative risk. For example, locations near sinks with heavy
electrical use should be retrofitted with GFCI protection before other locations.
GFCI’s must be tested before each use, but at least at 30-day intervals. Push the “test” button and
observe if the “reset” button pops out and the receptacle turns off. If this does not happen, the GFCI
is not functional and must be replaced.
CAUTION: Testing of a GFCI will disconnect all receptacles protected by the GFCI. Before testing,
determine which receptacles are protected. Verify that the interruption of power will not adversely
affect other activities.
Go to Table of Contents
Go to “How this program applies to you”.
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UC Berkeley Electrical Safety Program
Attachment V: Nationally Recognized Testing Laboratories (NRTL’s)
Go to Table of Contents
Whenever possible electrical equipment or electronic components used at UCB should bear the
mark of an NRTL. The enhanced safety and reliability of using equipment so tested and certified is
considered added value and improved safety in any component or piece of equipment. Look for
equipment with listing labels to assure greater safety and reliability in your research. Here are label
examples of some NRTLs at the time of this publication.
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UC Berkeley Electrical Safety Program
Attachment W: Electrical Safe Work Specifications
Go to Table of Contents
Go to “How this program applies to you”.
[RESERVED FOR FUTURE INSERTION / USE]
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UC Berkeley Electrical Safety Program
Attachment X: Arc Flash, Arc Fault, Ground Fault Calculation Specifications
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
This document is excerpted from a building improvements / renovation capital project conducted
on Clark Kerr Campus during the fall 2009 – spring 2010 time period. It guides the minimum
campus requirement for conducting Arc Flash / Ground Fault Electrical Safety Study
Parameters for new and renovation construction on campus. As part of compliance with the
UCB Electrical Safety Program, at minimum the requirements of this specification should be
incorporated into all new construction / building renovation project specification packages that
include electrical system installation / modifications.
SECTION 16081
ARC FLASH HAZARD STUDY
PART 1- GENERAL
1.01
DESCRIPTION
A.
The contractor shall furnish an arc flash hazard study as prepared by an Engineering
Services Company.
1.02
RELATED SECTIONS
A.
Section 16010 – Electrical General
B.
Section 16440 – Switchboards
C.
Section 16441 – Lighting and Appliance Panelboards
1.03
REFERENCES
A.
Institute of Electrical and Electronics Engineers, Inc. (IEEE):
1.
IEEE 1584 – Guide for Performing Arc Flash Hazard Calculations
2.
NFPA 70E – Standard for Electrical Safety in the Workplace
B.
American National Standards Institute (ANSI):
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UC Berkeley Electrical Safety Program
1.
ANSI C57.12.00 – Standard General Requirements for Liquid-Immersed Distribution,
Power, and Regulating Transformers
2.
ANSI C37.13 – Standard for Low-Voltage AC Power Circuit Breakers Used in
Enclosures
3.
ANSI C37.010 – Standard Application Guide for AC High-Voltage Circuit Breakers Rated
on a Symmetrical Current Basis
4.
ANSI C 37.41 – Standard Design Tests for High-Voltage Fuses, Distribution Enclosed
Single-Pole Air Switches, Fuse Disconnecting Switches and Accessories.
C.
1.04
CEC-California Electrical Code
SUBMITTALS FOR REVIEW/APPROVAL
A.
The arc flash incident energy and flash safety labeling shall be submitted to the Architect
prior to receiving final approval of the distribution equipment shop drawings and/or prior to
release of equipment drawings for manufacturing. If formal completion of the studies may cause
delay in equipment manufacturing, approval from the Architect may be obtained for preliminary
submittal of sufficient study data to ensure that the selection of device and characteristics will be
satisfactory.
B.
Arc flash evaluation and required protective FR clothing class signage
for all electrical equipment.
1.05
SUBMITTALS FOR CONSTRUCTION
A.
The results of the arc flash incident energy and flash safety labeling shall be
summarized in a final report. Submit four (4) bound copies of the complete final report.
B.
The report shall include the following sections:
1.
One-line diagram.
2.
Arc flash calculations and arc flash values, protective clothing and procedure for all
electrical equipment.
3.
1.06
Executive Summary.
QUALIFICATIONS
A.
The arc flash hazard study shall be conducted under the supervision and approval of a
Registered Professional Electrical Engineer skilled in performing and interpreting the arc flash
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UC Berkeley Electrical Safety Program
hazard study. The Registered Professional Electrical Engineer shall be registered in California
and a full-time employee of the Engineering Services Company.
PART 2 – PRODUCT
2.01
STUDY
A.
Contractor to furnish arc flash hazard study as prepared by Engineering Services
Company. Study shall include service from campus utility down to lighting and power
panelboards.
B.
Provide arc flash evaluation and labeling for all electrical equipment with signage as
required by NEC 110.16.
2.02
DATA COLLECTION
A.
Contractor shall furnish all data as required by the arc flash hazard study.
2.03
ARC FLASH HAZARD STUDY
A.
Use typical conductor impedances based on IEEE Standards 141-1993.
B.
Transformer design impedances shall be used when test impedances are not available.
C.
Provide the following:
1.
Calculation methods and assumptions.
2.
Selected base per unit quantities.
3.
One-line diagram of the system being evaluated.
4.
Source impedance data, including electric utility system and motor fault contribution
characteristics.
5.
Typical calculations.
6.
Tabulations of calculated quantities.
7.
Results, conclusions, and recommendations.
2.04
REPORT SECTIONS
A.
Input Data:
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UC Berkeley Electrical Safety Program
1.
Cable and conduit materials.
2.
Transformers.
3.
Circuit resistance and reactive values.
B.
Arc Flash Study to include:
1.
Perform an arc flash hazard study.
2.
The study shall be calculated by means of the SKM PowerTools for Windows computer
software package. Pertinent data, rationale employed, and assumptions in developing the
calculations shall be incorporated in the introductory remarks of the study.
3.
The study shall be in accordance with applicable NFPA 70E, OSHA 29-CFR, Part 1910
Sub part S and IEEE 1584 Standards.
4.
Determine the following
a.
Flash Hazard Protection Boundary.
b.
Limited Approach Boundary.
c.
Restricted Boundary.
d.
Prohibited Boundary.
e.
Incident Energy Level.
f.
Required Personal Protective Equipment Class.
g.
Type of Fire Rated Clothing.
5.
Produce an Arc Flash Warming label listing items a-g above. Labels shall be printed in
color and be printed on adhesive backed Avery labels.
6.
Produce Bus Detail sheets that list the Items 4.a through g from above and the following
additional items:
a.
Bus Name.
b.
Upstream Protective Device Name, Type and Settings.
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c.
7.
Bus Line to Line Voltage.
Produce Arc Flash Evaluation Summary Sheet listing the following additional items:
a.
Bus Name.
b.
Upstream Protective Device Name, Type and Settings.
c.
Bus Line to Line Voltage.
d.
Bus Bolted Fault.
e.
Protective Device Bolted Fault Current.
f.
Arcing Fault Current.
g.
Protective Device Trip/Delay Time.
h.
Breaker Opening Time.
i.
Solidly Grounded Column.
j.
Equipment Type.
k.
Gap.
l.
Arc Flash Boundary.
m.
Working Distance.
n.
Incident Energy.
o.
Required Protective Fire Rated Clothing Type and Class.
PART 3 – EXECUTION
INSTALLATION
Install arc flash hazard warning labels on all equipment. In electrical rooms, install label on face
of equipment. Where panelboards are visible to the building occupants, install label on the
inside face of the panelboard door.
END OF SECTION
Click here to download this form as a .pdf file.
Go to Table of Contents
Go to “How this program applies to you”.
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ATTACHMENT Y – EH&S FAQ / FACT SHEET
EH&S FACT
SHEET
Electrical Safety
This fact sheet provides “awareness level” information of electrical hazards and their safety
program controls. For those doing electrical work; hiring or overseeing electrical contractors;
developing or purchasing research or facility electrical equipment; attaching to or working on
facility / utility electrical systems, please see the UC Berkeley Electrical Safety Program for
guidance, safe work practices, equipment development guidance, procurement procedures, and
code compliance requirements.
Go to the beginning of the UC Berkeley Electrical Safety Program
(Click on any question in the Table of Contents below to go to the answer.)
Table of Contents
Why should you be concerned about electrical hazards? ..............................................85
Electricity: The Basics ...................................................................................................... 86
What affects the flow of electricity? ................................................................................86
How does water affect the flow of electricity? ................................................................86
What causes shocks?....................................................................................................86
What effect do shocks have on the body? .....................................................................87
Effects of Electric Current in the Human Body .................................................................... 87
What kind of burns and other injuries can a shock cause? ............................................88
Why do people sometimes “freeze" when they are shocked? ........................................88
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UC Berkeley Electrical Safety Program
What should you do if someone" freezes" to a live electrical contact? ...........................89
How can you tell if a shock is serious? ..........................................................................89
What is the danger of static electricity?..........................................................................89
Protection Against Electrical Hazards ................................................................................ 90
What is the best way to protect yourself against electrical hazards? ..............................90
What protection does insulation provide? ......................................................................90
How do you identify different types of insulation? ..........................................................90
What is guarding and what protection does it offer? ......................................................91
What is grounding and what protection does it offer? ....................................................91
Basic Facility Wiring - 101 .............................................................................................92
What are circuit protection devices and how do they work? ...........................................92
What work practices help protect you against electrical hazards? .................................93
How can you protect yourself against metal parts that become energized? ...................93
How can you prevent an accidental or unexpected equipment startup?.........................94
How can you protect yourself from overhead power lines? ............................................94
What protection does personal equipment offer? ...........................................................95
What role do tools play in electrical safety? ...................................................................95
What special training do qualified and authorized personnel need?...............................95
How do safety and health programs control electrical hazards? ....................................96
Why should you be concerned about electrical hazards?
Electricity has long been recognized as a serious workplace hazard, exposing personnel to
electric shock, electrocution, burns, fires, and explosions. In 1999, for example, 278 workers
died from electrocutions at work, accounting for almost 5 percent of all on-the-job fatalities that
year, according to the Bureau of Labor Statistics. What makes these statistics more tragic is that
most of these fatalities could have been easily avoided.
Go to FAQ Table of Contents
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UC Berkeley Electrical Safety Program
Electricity: The Basics
What affects the flow of electricity?
Electricity is a flow of electrons from a point of higher electrical potential to a point of lower
electrical potential. The amount of difference between the electrical potentials is the available
“pressure” or “voltage” between them. Electrons flow more easily through some materials than
others. Some substances such as metals generally offer very little resistance to the flow of
electric current and are called “conductors." A common but perhaps overlooked conductor is the
earth. Glass, plastic, porcelain, clay, pottery, dry wood, and similar substances generally slow or
stop the flow of electricity. They are called “insulators." Air, which is normally an insulator, can
become a conductor when enough voltage, moisture or pollutants are present as occurs during
an electric-arc or lightning stroke.
Go to FAQ Table of Contents
How does water affect the flow of electricity?
Pure water is a poor conductor. But small amounts of impurities in water like salt, acid, solvents,
or other materials can turn water itself and substances that generally act as insulators into
conductors. Dry wood, for example, generally slows or stops the flow of electricity. But when
saturated with water, wood turns into a conductor. The same is true of human skin. Dry skin has
a fairly high resistance to electric current flow. But when skin is moist or wet, it acts as a
conductor. This means that anyone who is sweating or working with electricity in a damp or wet
environment needs to exercise extra caution to prevent electrical shock or exposure to other
hazards.
Go to FAQ Table of Contents
What causes shocks?
Electricity travels in closed circuits normally through a conductor and always takes the path of
least resistance between two different electrical potentials. Sometimes a person's body, which
is an efficient conductor of electricity, mistakenly becomes part of the electric circuit. This can
cause an electrical shock. Shocks occur when a person's body completes the circuit path
between:
 Both wires of an electric circuit;
 One wire of an energized circuit and the ground;
 A metal part that accidentally becomes energized due, for example, to a break in its
insulation; or
 Another “conductor" that is carrying a current of different electrical potential than the
body.
When a person receives a shock, electricity flows from higher electrical potential, between parts
of the body or through the body to a “ground”, a lower electrical potential or the earth.
Go to FAQ Table of Contents
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What effect do shocks have on the body?
An electric shock can result in anything from a slight tingling sensation to immediate cardiac
arrest. The severity depends on the following:




The amount of current (amps) flowing through the body,
The current's path through the body,
The length of time the body remains part of the circuit, and
The current's frequency.
Effects of Electric Current in the Human Body
Electrical current is measured in “amps” depending upon how much available current is present.
The higher the current the higher the number of amps available to ‘shock’ the body. The table
below shows the general relationship between the level of current exposure to a person and the
reaction they may experience when current flows from one of their hands to a foot for just 1
second. (Note: One “milli-amp” is 1/1000th of an amp.)
Electric Current
Exposure Level
Body’s Reaction
Below 1 milli-amp
Generally not perceptible
1 milli-amp
Faint tingle
5 milli-amps
Slight shock felt; not significantly painful but disturbing. Average
individual can let go. Strong involuntary reactions and muscle
spasms can lead to other injuries.
6–25 milli-amps
Painful shock, loss of muscular control*
6–25 milli-amps (women)
The freezing current or “let-go" range.*
An individual cannot let go at higher range, but can be thrown
away from the circuit if extensor muscles are stimulated.
9–30 milli-amps (men)
50–150 milli-amps
Extreme pain, respiratory arrest, severe muscular contractions.
Death is possible.
1 amp – 4.3 amps
Rhythmic pumping action of the heart ceases. Muscular
contraction and nerve damage occur; death likely.
10 amps or more…..
Cardiac arrest, severe burns; death probable
* If the extensor muscles are excited by the shock, the person may be thrown away from the
power source.
{Source: W.B. Kouwenhoven, " Human Safety and Electric Shock," Electrical Safety Practices, Monograph, 112, Instrument
Society of America, p. 93. November 1968.]
Go to FAQ Table of Contents
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UC Berkeley Electrical Safety Program
What kind of burns and other injuries can a shock cause?
Burns are the most common shock-related injury. An electrical accident can result in an
electrical burn, arc burn, thermal contact burn, or a combination of burns. In addition, arc-blasts
can cause shock waves and explosive forces that can propel shrapnel away from the blast
location, cause concussive forces that can injury persons nearby, and expose personnel to toxic
smoke and fire.
Electrical burns are among the most serious burns and require immediate medical attention.
They occur when electric current flows through tissues or bone, generating heat that causes
tissue damage.
Arc or flash burns result from extremely high temperatures caused by an electric arc or
explosion near the body. The blast can ignite flammable materials in the area or a person’s
clothing if not fire resistant. In addition, the shock-wave of the blast can cause concussive
injuries. Exposure to arc blast and resulting burn and impact injuries must be treated promptly.
Thermal contact burns are caused when the skin touches hot surfaces of overheated electric
conductors, conduits, or other energized equipment. Thermal burns also can be caused when
clothing catches on fire, as may occur when an electric arc is produced.
In addition to shock and burn hazards, high-energy arcs can damage equipment causing
fragmented metal to fly in all directions. Even low-energy arcs such as a static-electric discharge
can cause violent explosions in atmospheres that contain flammable gases, vapors, or
combustible dusts.
Go to FAQ Table of Contents
Why do people sometimes “freeze" when they are shocked?
When a person receives an electrical shock, sometimes the electrical stimulation causes the
muscles to contract. This “freezing" effect makes the person unable to pull free of the circuit. It is
extremely dangerous because it increases the length of exposure to electricity and because the
current causes blisters, which reduce the body's resistance and increases the current flow into
the body.
The longer the exposure, the greater is the risk of serious injury. Longer exposures at even
relatively low voltages can be just as dangerous as short exposures at higher voltages. Low
voltage does not imply low hazard.
In addition to muscle contractions that cause “freezing," electrical shocks also can cause
involuntary muscle reactions and spasms. These reactions can result in a wide range of other
injuries from collisions or falls, including bruises, bone fractures, and even death.
Go to FAQ Table of Contents
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What should you do if someone" freezes" to a live electrical contact?
If a person is “frozen" to a live electrical contact, shut off the electrical current immediately. If
this is not possible, use boards, poles, or sticks made of wood or any other nonconductive
materials and safely push or pull the person away from the contact. It's important to act quickly,
but remember to protect yourself from electrocution or shock in the process. Remember, your
body is a good electrical conductor and grabbing onto someone when they are “frozen” to a live
electrical contact will likely make you part of the electrical circuit with them.
Go to FAQ Table of Contents
How can you tell if a shock is serious?
A severe shock can cause considerably more damage than meets the eye. A victim may suffer
internal hemorrhages and destruction of tissues, organs, nerves, and muscles that aren't readily
visible including renal damage. If you or a coworker receives a painful shock, seek emergency
medical help immediately.
Go to FAQ Table of Contents
What is the danger of static electricity?
Static electricity also can cause a shock, though in a different way and generally not as
potentially severe as the type of shock described previously. Static electricity can build up on
the surface of an object and, under the right conditions, can discharge to a person, causing a
painful shock. The most familiar example of this is when a person reaches for a door knob or
other metal object on a cold, relatively dry day and receives a shock. This shock is likely not
life-threatening as the available current in a static discharge is usually quite low and immediately
dissipated when the discharge takes place.
However, static electricity also can discharge to an object with much more serious
consequences, as when friction causes a high level of static electricity to build up at a specific
spot on an object. This can happen simply through handling plastic pipes and materials or
during normal operation of rubberized drive or machine belts found in many worksites. Even air
passing through an ungrounded fan housing can cause static build-up on the housing. In such
cases, static electricity can potentially discharge when sufficient amounts of flammable or
combustible substances or dusts are located nearby and can cause an explosion. Grounding or
other measures may be necessary to prevent this static electricity buildup and reduce the
hazards of static discharge.
Go to FAQ Table of Contents
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UC Berkeley Electrical Safety Program
Protection Against Electrical Hazards
What is the best way to protect yourself against electrical hazards?
Most electrical accidents result from one of the following three factors:
 Unsafe equipment or installation,
 Unsafe environment, or
 Unsafe work practices.
Ways to prevent these accidents are through the use of insulation, guarding, grounding,
electrical protective devices, and safe work practices.
Go to FAQ Table of Contents
What protection does insulation provide?
Insulators such as glass, mica, rubber, or plastic used to coat metals and other conductors help
stop or reduce the flow of electrical current. This helps prevent shock, fires, and short circuits.
To be effective, the insulation must be suitable for the voltage used and conditions such as
temperature and other environmental factors like moisture, oil, gasoline, corrosive fumes, or
other substances that could cause the insulator to fail. Generally, the higher the voltage present
the more elaborate and ‘pure’ the insulator materials and methods will need to be to assure
safety.
Go to FAQ Table of Contents
How do you identify different types of insulation?
In most buildings and equipment, insulation on conductors is often color coded. Insulated
equipment grounding conductors usually are either solid green or green with yellow stripes.
Insulation covering grounded or “neutral” conductors is generally white or gray. Ungrounded
conductors (conductors with an electrical potential greater than ground) known as “hot wires" or
“live wires” often are black or red although they may be any color other than green, white, or
gray.
Before connecting electrical equipment to a power source, it's a good idea to check the
insulation for any exposed wires for possible defects. Insulation covering flexible cords such as
extension cords is particularly vulnerable to damage.
The insulation that covers conductors in non-construction applications is regulated by OSHA
codes, National Electrical Code, California Electrical Code, Wiring Design standards and
Protection requirements. All codes generally require insulation on circuit conductors. Codes also
specify that the insulation used should be suitable for the available voltage, amperages and
environmental conditions expected. Conductors used in temporary construction applications are
also regulated by codes.
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Go to FAQ Table of Contents
What is guarding and what protection does it offer?
Guarding involves locating or enclosing electric equipment to make sure people don't
accidentally come into contact with its live parts. Effective guarding requires equipment with
exposed parts operating at 50 volts or more to be placed where it is accessible only to
authorized people qualified to work with it. Recommended locations are a room, vault, or similar
enclosure; a balcony, gallery, or elevated platform; or a site elevated 8 feet (2.44 meters) or
more above the floor. Sturdy, permanent screens also can serve as effective guards. UC
Berkeley’s Electrical Safety Program has detailed design guidelines for researchers developing
electrical research equipment that includes guarding requirements, spacial clearances and
location requirements for exposed conductors to assure compliance with electrical safety codes.
Conspicuous signs must be posted at the entrances to electrical rooms and similarly guarded
locations to alert people to the electrical hazard and to forbid entry to unauthorized people.
Signs may contain the word “Danger," "Warning," or "Caution," and beneath that, appropriate
concise wording that alerts people to the hazard or gives an instruction, such as “Danger / High
Voltage / Keep Out".
Go to FAQ Table of Contents
What is grounding and what protection does it offer?
“Grounding" a tool, a piece of equipment or a specific part of an electrical system means
intentionally creating a low-resistance path that connects to the earth to prevent the buildup of
voltages, including a static charge. Grounding is often a permanent part of any functioning
electrical circuit. Grounding may also be added temporarily to electrical circuits or equipment by
maintenance or research personnel to ensure safety and that the equipment they are working
on cannot build-up an electrical charge greater than “ground”.
Grounding does not guarantee that you won't get a shock, be injured or killed by an electrical
current. It will, however, substantially reduce the risk, especially when used in combination with
other safety measures. Remember, electrical current flows from a higher electrical potential to a
lower electrical potential taking the path of least resistance. If all parts in an electrical system
are ‘grounded’, then they all have the same electrical potential and no electricity can ‘flow’
between the grounded parts. In certain situations such as manufacturing and research of
integrated circuits, or in flammable atmospheres, not only will all equipment be grounded, but
the people working in the area will be grounded by wearing electrically conductive fabrics
attached to ground as well. This will prevent any static electric build-up on their bodies and
clothing from ‘grounding’ and damaging the integrated circuits, or generating a spark that could
cause an explosion.
Various codes regulating Wiring Design and Electrical Safety/Protection require at times a
service or system ground as well as an equipment ground in non-construction / facility
applications. In addition, UC Berkeley may require additional grounding in unique situations
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UC Berkeley Electrical Safety Program
such as human subjects research and other situations where electrical safety must be totally
assured.
A facility’s service or “system ground” is designed to provide a safe and reliable connection to
the earth for all electrical equipment in the facility to protect machines, tools, and insulation
against damage, over-heating and fire, and people from electrical shock.
Go to FAQ Table of Contents
Basic Facility Wiring - 101
Most 120 / 240 volt electrical outlets have three or more wires installed in them as part of the
building’s electrical system. The “hot wire” has an electrical potential greater than ‘ground’ and
is one wire (120 volt) or two wires (240 volt) red or black in color. The white or gray “neutral” or
“grounded" conductor completes the electrical circuit from the point of electrical use (a light bulb,
motor, etc.) back to the building’s ground under normal conditions. The building’s ground is then
connected to a grounding rod literally buried in the ground under the building. At the generator
or supply transformer, the ground wire or neutral is also grounded through a ground rod and into
the earth. The earth actually completes the electrical circuit from the building back to the
transformer or generator!
The green “ground wire” is used to carry an electrical current away from a person to the
building’s ground if the equipment malfunctions. The green equipment ground helps protect the
equipment operator only. It furnishes a second path for the current to pass through from the
point of electrical use (a light bulb, motor, etc.) to the ground in the event the “neutral” wire or
equipment insulation / guarding malfunctions.
Go to FAQ Table of Contents
What are circuit protection devices and how do they work?
Circuit protection devices limit or stop the flow of current in the ‘hot wire’ automatically in the
event of a ground fault, overload, or short circuit in the wiring system. Well-known examples of
these devices are fuses, circuit breakers, ground-fault circuit interrupters (GFCIs), and arc-fault
circuit interrupters.
Simple fuses and circuit breakers open or break the circuit automatically when too much current
flows through them. When that happens, fuses melt or circuit breakers trip the circuit open.
Fuses and circuit breakers are designed to protect equipment, wires and other components
from overheating and open the circuit when there is a risk of a ground fault. They are NOT
designed to prevent you from getting an electric shock.
Ground-fault circuit interrupters, or GFCIs, are used in wet locations, construction sites, and
other high-risk areas. These devices interrupt the flow of electricity within as little as 1/40 of a
second to prevent electrocution. GFCIs continuously monitor and compare the amount of
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UC Berkeley Electrical Safety Program
current going into electric equipment with the amount of current returning from it along the circuit
conductors. If the difference exceeds 5 milliamperes, the device automatically shuts off the
electric power to the ‘hot wire’.
Arc-fault devices provide protection from the effects of arc-faults by recognizing characteristics
unique to arcing and by functioning to de-energize the circuit when an arc-fault is detected.
A person should never rely on the proper / automatic functioning of a circuit protection device to
safeguard their life. Circuit protection devices are rated in amps. Most building’s smallest
circuits are rated at 15 amps and often much more. The circuit protection device will provide at
least 15 amps to a circuit before it will trip and shut off. But, your body will start to be injured at
amperages of 5 milli-amps or more. That means at least 3000 times more current is available in
the typical building’s smallest power circuit than what can safely be tolerated by your body!
Therefore, always turn off or disconnect the power (and in some situations, even ‘lock and tag’ it
off) before working on electrical equipment, even if you’re just changing a light bulb!!
Go to FAQ Table of Contents
What work practices help protect you against electrical hazards?
Electrical accidents are largely preventable through safe work practices. Examples of these
practices include the following:
 De-energizing electric equipment before inspection or repair by applying and following
UC Berkeley’s Energy Isolation–Lock out Tag out Program,
 Keeping electric tools properly maintained,
 Exercising caution when working near energized lines, and
 Using appropriate protective equipment.
Go to FAQ Table of Contents
How can you protect yourself against metal parts that become
energized?
A break in an electric tool's or machine's insulation can cause its metal parts to become “hot" or
energized, meaning that they have electric potential greater than ground. Touching these
energized parts can result in an electrical shock, burn, or electrocution. The best way to protect
yourself when using electrical tools or machines is to establish a low-resistance path from the
device's metallic case to the ground. This requires an equipment grounding conductor, a lowresistance wire that directs unwanted current directly to the ground. A properly installed
grounding conductor has a low resistance to ground and greatly reduces the amount of current
that passes through your body. Cord and plug equipment with a three-prong plug is a common
example of equipment incorporating this ground conductor.
Another form of protection is to use “listed” or “labeled” portable tools, equipment and
appliances protected by an approved system of double insulation or its equivalent. Equipment
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UC Berkeley Electrical Safety Program
that is listed or labeled has been reviewed by an independent ‘third party’ agency known as a
“Nationally Recognized Testing Laboratory” (NRTL) that tests and verifies that the equipment is
designed and manufactured to a certain degree of quality and safety including double-insulation,
guarding and spacial clearance requirements. Examples of an NRTL are “Underwriter’s
Laboratory” (UL) and the “Electrical Testing Laboratory” (ETL) but there are others. Electrical
safety codes require that where such safe equipment design systems are employed, they must
be marked distinctively to indicate that the tool or appliance uses an approved double insulation
or other electrically safe system. At UC Berkeley, the Electrical Safety Program requires that all
commercial electrical equipment purchased by the University must be “listed” or “labeled” by an
NRTL.
Go to FAQ Table of Contents
How can you prevent an accidental or unexpected equipment startup?
Proper Energy Isolation – Lockout Tagout procedures protect you from the dangers of the
accidental or unexpected startup of electrical equipment and are required for general industry by
OSHA codes. UC Berkeley’s Energy Isolation–Lock out Tag out Program outlines the
procedures that ensure electrical equipment is de-energized before it is repaired or inspected
and protects you against electrocution or shock.
The first step before beginning any inspection or repair job is to turn the current off at the switch
box and padlock the switch in the OFF position. This applies even on so-called low-voltage
circuits. Once locked, securely tagging the switch or controls of the machine or equipment being
locked out of service clarifies to everyone in the area which equipment or circuits are being
inspected or repaired and by whom.
Only qualified and authorized persons who have been trained in energy isolation procedures are
allowed to maintain electrical equipment. Each person must have their own lock for locking out
the electrical disconnect. No two of the locks used match, and each key fits just one lock. All
employees who are working on a given piece of equipment must lock out its switch with a multilock hasp and with each of their individual locks applied. Besides the person who ‘owns’ the
lock, only a person’s supervisor is permitted to remove a person’s lock, and this is only when
the supervisor can verify the person is safe and away from the equipment.
Go to FAQ Table of Contents
How can you protect yourself from overhead power lines?
Before working under or near overhead power lines, ensure that you maintain a safe distance to
the lines and, for very high-voltage lines, ground any equipment such as cranes that can
become energized. If working on power lines, ensure that the lines have been de-energized and
grounded by the owner or operator of the lines. Other protective measures like guarding or
insulating the lines help prevent accidental contact.
Employees unqualified to work with electricity, as well as mechanical equipment, should remain
at least 10 feet (3.05 meters) away from overhead power lines. If the voltage is more than
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UC Berkeley Electrical Safety Program
50,000 volts, the clearance increases by 4 inches (10 centimeters) for each additional 10,000
volts.
When mechanical equipment is operated near overhead lines, employees standing on the
ground should avoid contact with the equipment unless it is located outside the danger zone.
When factoring the safe standoff distance, be sure to consider the equipment's maximum reach.
Go to FAQ Table of Contents
What protection does personal equipment offer?
Employees who work directly with electricity must follow UC Berkeley’s Electrical Safety
Program – Appendix 1 “Hot Work Permit” Procedure and use the personal protective equipment
required for the jobs they perform as outlined in that procedure. This equipment may include
rubber insulating gloves, hoods, sleeves, matting, fire resistant clothing, insulated blankets, line
hose, and industrial protective helmets designed to reduce electric shock hazard. All help
reduce the risk of electrical accidents.
Go to FAQ Table of Contents
What role do tools play in electrical safety?
Appropriate and properly maintained tools help protect workers against electric hazards. It's
important to maintain tools regularly because it prevents them from deteriorating and becoming
dangerous. Check each tool before using it. If you find a defect, immediately remove it from
service and tag it so no one will use it until it has been repaired or replaced.
When using a tool to handle energized conductors, check to make sure it is designed and
constructed to withstand the voltages and stresses to which it has been exposed. Tools
specifically designed for use in at 1000 volts and higher will be labeled as such to assure safety.
If in doubt, never use a tool that you are not sure is rated for the voltages that you will be
working at.
Go to FAQ Table of Contents
What special training do qualified and authorized personnel need?
All “Qualified” and “Authorized” personnel must be trained to be thoroughly familiar with the
electrical safety procedures for their particular jobs. UC Berkeley’s Electrical Safety Program
details the requirements, qualifications and training needed for a person to be considered
“Qualified” to do electrical work at various hazard levels. This qualification is reviewed and
approved by the person’s supervisor. In addition, the Program requires that a person must be
“authorized” to conduct electrical work on a specific piece of equipment, or a facility. This
authorization may be by the equipment’s “owner department”, an “owner PI”, a Project Manager,
or by the person’s supervisor depending upon the situation. Moreover, good judgment and
common sense are integral to preventing electrical accidents. When working on electrical
equipment, for example, some basic procedures to follow are to:
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UC Berkeley Electrical Safety Program




De-energize the equipment following UC Berkeley’s Energy Isolation Program,
Use lockout and tag procedures to ensure that the equipment remains de-energized,
Use insulating protective equipment, and
Maintain a safe distance from energized parts.
Go to FAQ Table of Contents
How do safety and health programs control electrical hazards?
The safety measures detailed in this fact sheet are a primmer on UC Berkeley’s Electrical
Safety Program which guides the University’s measures to control electrical hazards. The
responsibility for this program is delegated by the Chancellor to EH&S for program development
/ maintenance and via the program to the Campus’ Electrical Engineer, Safety Engineer and
Electrical Safety Committee (ESC).
Everyone at UC Berkeley has the right to work in a safe environment. Safety and health add
value to your department’s business, your research, your safety and your direct report’s /
coworker’s safe workplace. Through cooperative efforts of training on and application of the UC
Berkeley Energy Isolation – Lock out Tag out Program and the UC Berkeley Electrical Safety
Program, all personnel can learn to identify and eliminate or control electrical hazards and
achieve an injury free safe workplace.
Go to FAQ Table of Contents
Above FAQ / Fact Sheet content was excerpted and adapted for UCB use from the Fed-OSHA
website on July 9, 2010. Please go to http://www.osha.gov/Publications/3075.html for additional
information and the complete publication from Fed-OSHA.
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