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Transcript
Laboratory Standard Operating Procedure –
Electrical Apparatus Used or Fabricated in Laboratory/Research Areas –
Risk Assessment
The Pennsylvania State University
Office of Environmental Health and Safety
6 Eisenhower Parking Deck
University Park, PA 16802
Please fill out the form and then print it on your local printer and place in your Laboratory and
Research Safety Plan.
Date 7/12/16
Location: Penn State Engineering Lab
Principal Investigator Dr. John Doe, Professor of Electrical Engineering
Room and Building 11106 - Building 101
Phone Number 123-456-3300
A short description was added to this risk assessment:
The Electric Machines laboratory is used for faculty and undergraduate student research in the
area of power electronics, electric machines, and electric drives. The laboratory is equipped with
a variety of regulated DC power supplies, 3 phase inverters, dSpace rapid prototyping tools,
electric motors, and a small dynamometer. Research projects have included development,
implementation, and testing of various inverters for motor drives (resonant pole, GaN based
drive, sensorless control of PMSM, etc.). The nature of the research often involves working with
live electric circuits (inverters) operating at DC bus voltages of less than 50V.
(Check to Acknowledge)
Section 1:
X Electrical task involves electrical apparatus used or fabricated in laboratory/research areas.
-Does not include common electrical devices used as originally intended by the
manufacturer. Such items include but aren’t limited to those bought at any department
store, appliances, hot plates, power strips, wood/metal wooding machines, refrigerators,
microwaves, ovens, etc.
Section 2: Determine if interaction with live parts is necessary.
NOTE: In a lab environment live work is only permitted when:
Page 1 of 10


Deenergizing is not possible due to equipment design or operational limitations.
Examples of this situation would include diagnostic work such as voltage
measurements, troubleshooting, and testing of electrical equipment.
Live parts are operating at less than 50 volts and there is no increased exposure
to electrical burns or to explosion due to electrical arcs.
Will there be interaction with live parts?:Yes live up to 42 volts however have an additional
variable power supply that is capable of supplying 150 volts. Currently, use equipment that
has the capability to use 42 volts
No. Equipment will be disconnected from power source (i.e Lockout Tagout). If
answered NO, the rest of this document can be left blank. Equipment can be unplugged
and also has an on/off switch.
X Yes, explain the tasks where the person/s are required to interact with live parts:
NOTE: Be aware of power source and capabilities. (i.e. low voltage, high power devices,
switch testing, capacitors) Diagnostic testing required while powered. Supplies are
purchased however the inverter and/or motor drive is fabricated.
Section 3: If equipment is “used” (not purchased new from the manufacturer), determine if there
are any known issues/problems with the equipment:
No known issues/problems
X Yes: Has issues/problems.
If Yes, Explain issue/problems and
corrective actions to fix:
Potential use issues/problems:
Experimental by nature, power electronic
circuit may not be wired correctly, etc.
Controls: perform proper visual
inspections before each use, ensure design
incorporates proper circuit protection into
power supply or experiment, add controls
such as fuses, etc.
Section 4: Perform a visual inspection of the equipment to look for damage:
X No damage
Yes: Has damage.
If Yes, Explain damage and corrective
actions to fix:
Page 2 of 10
Section 5: Perform a visual inspection of the equipment to ensure it is properly grounded to
prevent shock.
Not properly grounded. Explain what will
X - Yes: properly grounded.
be done to ensure proper grounding of
Check all that apply:
equipment:
X - Equipped with a 3-prong plug
A portable GFCI outlet is used
Equipment is connected to a wall outlet
that is a GFCI
X Equipment is connected to a circuit
breaker that is designed to operate as a
GFCI
Equipment is hard wired into a building
electrical panel that has a proper ground
established. Verified by OPP
electrician/or electrician.
Section 6: Determine if additional safety devices/equipment can be installed on/with the
equipment to reduce hazard (i.e. DC Isolation Monitors). Ensure power supply grounded.
None required/Not Applicable
X Yes: If yes, explain what additional devices will be
utilized:
Ideal work environment – nonconductive work surface, clean work environment, adequate
electrical power supply, good housekeeping, use of rated and proper electrical equipment.
etc.
Section 7: Distinguish live parts from other parts of equipment:
Not necessary: All live parts are enclosed during normal operation.
X Live parts may be exposed during normal operation. How will these parts be distinguished
(color, notes, labels, signs, etc):
Nothing physical, not operating unattended, access control, SOP, training, low voltage
Section 8: Determine how to insulate/guard/enclose/limit access to energized electrical
conductors/circuits/parts 50 volts or higher in the system to reduce/eliminate exposure during
normal operation:
X Not Necessary: Less than 50 volts
 Necessary. Explain:
o NOTE: Only non-conductive devices can be used. . If higher than 50 volts normal
operation would be exposed for trouble shooting, Need to reference PPE for
electrical safety program
Page 3 of 10
Section 9: Determine the highest nominal system voltage:
X What is the nominal voltage? Variable power supply equipment in lab has the ability to use
150 volts but lab does not have the equipment to utilize it currently. Proper PPE will be assessed
and used if working with equipment greater than 50 volts.
Section 10: Determine minimum approach distances to exposed live parts for shock protection
(utilizing Appendix B: Approach Boundaries to Energized Electrical Conductors or Circuit
Parts for Shock Protection seen below as retrieved from the PSU Energized Electrical Safety
Program) :
Appendix B
Approach Boundaries to Energized Electrical Conductors or Circuit Parts for Shock Protection
(All dimensions are distance from fixed live part to employee)
Alternating Current (AC)
Nominal System
Voltage
Limited
Restricted Approach
Approach
Boundary
Boundary
Less than 50 V
Not Specified
Not Specified
50 V to 150 V
3 feet, 6 inches
Avoid Contact
151 V to 750 V
3 feet, 6 inches
1 foot
751 V to 15 kV
5 feet
2 feet, 2 inches
Over 15 kV or a movable conductor (a condition in which the distance
between the conductor and a person is not under the control of the
person)
See NFPA 70 E Table 130.4 (D)(a)
Direct Current (DC)
Nominal Potential
Limited Approach
Restricted Approach Boundary
Difference
Boundary
< 100 V
Not Specified
Not Specified
100 V to 300 V
3 feet, 6 inches
Avoid Contact
301 V to 1 kV
3 feet, 6 inches
1 foot
Over 1 kV or a movable conductor (a condition in which the distance between the conductor and a person
is not under the control of the person)
See NFPA 70 E Table 130.4 (D)(b)
Definitions
 Limited Approach Boundary is an approach limit at a distance from an exposed live part within which a
shock hazard exists.
 Restricted Approach Boundary is a distance from an exposed energized electrical conductor or circuit part
within which there is an increased likelihood of electric shock, due to electrical arc-over combined with
inadvertent movement, for personnel working in close proximity to the energized electrical conductor or
circuit part.
List the distances:
Page 4 of 10


Limited Approach Boundary :3 feet six inches
Restricted Approach Boundary :Avoid Contact
Section 11: Determine the appropriate PPE for each task:
 If equipment is hard wired into the facility/building electrical system utilize Appendices
below.
-Appendix C: Arc flash Hazard Identification
-Appendix D: Arc flash hazard PPE categories for Alternating Current (AC) Equipment
& Direct Current (DC) Equipment
-Appendix E: Personal Protective Equipment
X If equipment is cord and plug connected perform a PPE hazard assessment based on the
manufactures recommendations, equipment design and voltage. Use Appendices C-E below for
guidance. Note that arc flash PPE and/or shock protection PPE may be necessary.
Appendix C
Arc flash Hazard Identification – Alternating Current Equipment (AC) and Direct
Current Equipment (DC)
Task
Equipment Condition
Reading a panel meter
Any
while operating a
meter switch
All of the following:
Normal
The
equipment
is
properly
installed
operation
The equipment is properly maintained
of a circuit All equipment doors are closed and secured
breaker
All equipment covers are in place and secured
(CB),
There is no evidence of impending failure
Note: All of the following requirements must be met to satisfy the “no arc flash PPE
switch,
contactor, required” scenario:
1) Covers/panels that enclose the circuit breaker (CB), switch, contactor, or starter are in place,
or starter
and secure.
2)
3)
4)
5)
6)
7)
8)
9)
No visual damage to the enclosure of the circuit breaker (CB), switch, contactor, or starter.
No visual damage to the circuit breaker (CB) switch, switch, contactor, or starter.
No visual damage to the wires/conduits at entry/exit points to the enclosure.
No knockouts missing.
No evidence of water/liquid damage (puddling, rust, chemicals).
No evidence of heat/fire damage (discoloration).
No bolts, screws, fasteners missing.
No exposed live parts of the enclosure (proper blanks used to cover empty circuit breaker
locations)
If conditions in 1-9 are found to be satisfactory, a circuit breaker (CB), switch, contactor, or
starter can be used to turn off/on a circuit without PPE.
Page 5 of 10
Arc Flash
PPE
Required
No
No
*********Resetting a tripped breaker*********
If conditions in 1-9 are found to be satisfactory and circuit breaker operation training has been
completed, a tripped circuit breaker can be reset without PPE ONLY IF after investigation reveals
a probable cause of the trip (overloaded circuit). ADDITIONALLY, the circuit breaker is only
permitted to be reset only 1 time.
A person who has been qualified to troubleshoot an electrical circuit (i.e. electrician) must be
notified if the breaker trips a 2nd time.
Normal
operation of a
circuit breaker
(CB), switch,
contactor, or
starter
One or more of the following:
The equipment is not properly installed
The equipment is not properly maintained
Equipment doors are open or not secure
Equipment covers are off or not secured
There is evidence of impending failure
Yes
Appendix C
Arc flash Hazard Identification – Alternating Current Equipment (AC) and Direct
Current Equipment (DC)
Task
Equipment Condition
For ac systems: Work on energized electrical conductors
and circuit parts, including voltage testing
For dc systems: Work on energized electrical conductors
and circuit parts of series-connected battery cells, including
voltage testing
Voltage testing on individual battery cells or individual
multi-cell units
Any
Arc Flash
PPE
Required
Yes
Any
Yes
Removal of bolted covers (to expose bare energized
electrical conductors and circuit parts). For dc systems, this
includes bolted covers, such as battery terminal covers
Removal of battery intercell connector covers
Page 6 of 10
All of the following:
The equipment is properly installed
The equipment is properly maintained
Covers for all other equipment are in place and
secured
There is no evidence of impending failure
One or more of the following:
The equipment is not properly installed
The equipment is not properly maintained
Equipment doors are open or not secure
Equipment covers are off or not secured
There is evidence of impending failure
Any
All of the following:
The equipment is properly installed
The equipment is properly maintained
Covers for all other equipment are in place and
secured
There is no evidence of impending failure
One or more of the following:
The equipment is not properly installed
The equipment is not properly maintained
Equipment doors are open or not secure
Equipment covers are off or not secured
There is evidence of impending failure
No
Yes
Yes
No
Yes
Appendix C
Arc flash Hazard Identification – Alternating Current Equipment (AC) and Direct
Current Equipment (DC)
Arc Flash
Task
Equipment Condition
PPE
Required
Opening hinged door(s) or cover(s) (to expose bare energized
Any
Yes
electrical conductors and circuit parts)
Work on control circuits with exposed energized electrical
Any
No
conductors and circuit parts, 120 volts or below without any
exposed energized equipment over 120 V including opening
of hinged covers to gain access
Work on control circuits with exposed energized electrical
Any
Yes
conductors and circuit parts, greater than 120 V
Insulated cable examination with no manipulation of cable
Any
No
Insulated cable examination with manipulation of cable
Any
Yes
Work on exposed energized electrical conductors and circuit
Any
Yes
parts of equipment directly supplied by a panelboard or motor
control center
For dc systems, insertion or removal of individual cells or
Any
Yes
multi-cell units of a battery system in an enclosure
For dc systems, insertion or removal of individual cells or
Any
No
multi-cell units of a battery system in an open rack
For dc systems, maintenance on a single cell of a battery
Any
No
system or multi-cell units in an open rack
For dc systems, work on exposed energized electrical
Any
Yes
conductors and circuit parts of utilization equipment directly
supplied by a dc source
Additional Information:
Hazard Identification is one component of risk assessment. Rick assessment involves a
determination of the likelihood of occurrence of an incident, resulting from a hazard that could
cause injury or damage to health. The assessment of the likelihood of occurrence contained in
the table does not cover every possible condition or situation. Where this table indicates that arc
flash PPE is not required, an arc flash is not likely to occur.
The phrase “properly installed”, as used in this table, means that the equipment is installed in
accordance with applicable industry codes and standards and the manufacturer’s
recommendations.
The phrase “properly maintained”, as used in this table, means that the equipment has been
maintained in accordance with manufacturer’s recommendations and applicable industry codes
and standards.
The phrase “evidence of impending failure”, as used in this table , means that there is evidence
of arcing, overheating, loose or bound equipment parts, visible damage, deterioration, or other
damage.
Page 7 of 10
Appendix D
Arc flash hazard PPE categories
Alternating Current (AC) Equipment
Equipment
Panelboards or other equipment rated 240 V and below
Parameters:
Maximum of 25 kA short circuit current available; maximum of 0.03 sec (2 cycle) fault
clearing time; working distance 18 in.
Panelboards or other equipment rated greater than 240 V and up to 600 V
Parameters:
Maximum of 25 kA short circuit current available; maximum of 0.03 sec (2 cycle) fault
clearing time; working distance 18 in.
Other 600 V class equipment (277 V through 600 V nominal)
Parameters:
Maximum of 65 kA short circuit available; maximum of 0.03 sec (2 cycle) fault clearing
time; working distance 18 in.
Arc Flash PPE
Category
1
2
2
Arc Flash Boundary
For AC systems that are 600 volts or less, the arc flash boundary shall be a minimum of 20 feet or the entire room if
a boundary of 20 feet cannot be obtained (i.e. room is smaller than 20 feet). If the equipment has an NFPA 70E
label attached its stated arc flash boundary should be used.
Direct Current (DC) Equipment
Equipment
Arc Flash
Arc-Flash
PPE
Boundary
Category
Storage batteries, dc switchboards, and other dc supply sources 100V or greater less but less than 250V.
Parameters:
Voltage: 250 V
Maximum arc duration and working distance: 2 sec @ 18 in.
Short-circuit current less than 4 kA
1
3 feet
Greater than 4 kA short-circuit current but less than 7 kA
2
4 feet
Greater than 7 kA short-circuit current but less than 15 kA
3
6 feet
Storage batteries, dc switchboards, and other dc supply sources 250 V or greater but less than 600V.
Parameters:
Voltage: 600 V
Maximum arc duration and working distance: 2 sec @ 18 in.
Short-circuit current less than 1.5 kA
1
3 feet
Greater than 1.5 kA short-circuit current but less than 3 kA
2
4 feet
Greater than 3 kA short-circuit current but less than 7 kA
3
6 feet
Greater than 7 kA short-circuit current but less than 10 kA
4
8 feet
Additional Information:
“Short-circuit current” as used in this table, is determined from the dc power system maximum available shortcircuit, including the effects of cables and any other impedances in the circuit. Power system modeling is the best
method to determine the available short-circuit current at the point of the arc. Battery cell short-circuit current can
be obtained from the battery manufacturer.
The methods for estimating the dc arc flash incident energy that were used to determine the categories for this table
are based on open-air incident energy calculations. Open-air calculations were used because many battery systems
and other dc process systems are in open areas or rooms. If the specific task is within an enclosure, it would be
prudent to consider additional PPE protection beyond the value shown in this table. Research with ac arc flash has
shown a multiplier of as much as 3x for arc-in-a-box versus open air.
Page 8 of 10
PPE Category
1
2
Appendix E: Personal Protective Equipment
PPE
Arc Rated Clothing, Minimum Arc Rating of 4 cal/cm2
Arc-rated long-sleeve shirt and pants or Arc- rated coveralls
Arc-rated face shield (see Note 2) or arc flash suit hood
Arc-rated jacket, parka, rainwear or hard hat liner (AN)
Protective Equipment
Hard hat
Safety glasses or safety goggles
Hearing protection (ear canal inserts)
Heavy duty leather gloves with rubber insulating gloves (see note 1)
Leather footwear (AN)
Arc Rated Clothing, Minimum Arc Rating of 8 cal/cm2
Arc-rated long-sleeve shirt and pants or arc-rated coveralls
Arc-rated flash suit hood or arc-rated face shield (note 2) AND arc-rated balaclava
Arc-rated jacket, parka, rainwear, or hard hat liner (AN)
Protective Equipment
Hard hat
Safety glasses or safety goggles
Hearing protection (ear canal inserts)
Heavy duty leather gloves with rubber insulating gloves (see note 1)
Leather footwear
AN: As Needed AR: As Required
Notes:
1.
2.
If rubber insulating gloves with leather protectors are used, additional leather or arc-rated gloves are not required. The
combination of rubber insulating gloves with leather protectors satisfies the arc flash protection requirement.
Face shields are to have wrap-around guarding to protect not only the face but also the forehead, ears, and neck, or,
alternatively, an arc-rated arc flash suit hood is required to be worn.
Check all PPE required for the task utilizing <50 volts DC:
X Safety Glasses
Arc Flash
Face Shield
X Leather Gloves
Arc Flash
Balaclava
Voltage Rated Rubber Gloves (NOTE:
gloves are required to be sent to a 3rd party
every 6 months to ensure they are still in a nonconductive state. Alternatively a new pair of
gloves can be purchased every 6 months and the
old pair discarded.)
Arc Flash Clothing
Section 12: Determine the proper insulated tools needed:
No insulated tools are required because no work on live parts will be done.
X Yes, live work may be necessary, such as testing/troubleshooting, the following tools are
required to be insulated (pliers, sockets, strippers, crimpers, wrenches, etc):
 List the tools below:
Pliers
Strippers
Screw driver
Crimpers
Page 9 of 10
Section 13: Determine the appropriate voltage rated test instruments to utilize:
No test instruments are required
X Yes, test instruments are required:
 List the test instruments below:
Voltage meter
Section 14: Determine and identify appropriate emergency shutdown/shutoff procedures:
Explain: SOP – Unplug Equipment
Section 15: Determine the appropriate energy isolation procedures to use in order to perform
servicing/maintenance on the equipment (i.e. Lockout/Tagout (LOTO) procedures):
X Cord and plug powered.
 Unplug cord and ensure unauthorized persons do not re-energize (cord to be kept
under the continuous control of the person performing the servicing/maintenance)
Hard-wired via circuit breaker/disconnect lever
 Step 1 – ID energy source
 Step 2 – Notify Others
 Step 3 – Shutdown equipment (how it is typically shutdown)
 Step 4 – Isolate equipment (open circuit breaker/disconnect)
 Step 5 – LOTO equipment (attach lock and tag to circuit breaker/disconnect)
 Step 6 – Release stored energy
 Step 7 – Verify Isolation (try to start equipment and/or test for voltage)
 Step 8 – Perform servicing/maintenance
 Step 9 – Release form LOTO
Section 16: Describe Procedure/Task/Process. (NOTE: attaching the task specific
procedure/process/instructions/SOP to this form is permitted):
See Laboratory and Safety Research Plan and Unit Specific Plan
Page 10 of 10