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PU 430
Unit 9
Chapters 7, 12, 13
Heat Waves
Chapter Seven
Heat Waves
 One of the most subtle yet most lethal
disasters
 These produce greater mortality than
hurricanes, tornadoes, & earthquakes
combined
 Future predictions of heat wave
occurrences & severity look harsh
 The human body maintains an internal
temperature within a very narrow range
 When environmental conditions or physical
activity generate more heat than the body
can regulate, there is an increased risk for
heat-related illnesses
 Dehydration is also a critical risk factor for
heat illness
 The NWS has developed a Heat Index to
reflect the apparent temperature when
humidity is factored into the conditions
Effects on the Human Body
 All deaths from heat waves are
preventable
 Heat waves can be predicted & the
measures needed to successfully manage
their impact are well understood &
inexpensive
 It is important that the community
engage in preparedness activities
specifically for a heat emergency
Prevention
 This refers to the alteration of the environment resulting
from urban development combined with the added heat
generated by population density
 The combination of the following factors contributes to a
rise in urban & suburban temperatures:
◦ Urban industrial & transportation activities
◦ The reduction in vegetation across urban areas reduces the
shading of buildings & surfaces
◦ Dark colored roofs & pavements are less reflective & absorb
more heat
◦ Taller structures block air movement & further reduce the
rate at which these surfaces can cool
 Mitigation measures to reduce urban heat islands are
simple & offer benefits far beyond the reduction in heat
Urban Heat Island Mitigation
 The most important steps a community can take is to identify
vulnerable populations in advance & determine the best
methods to get information into their hands
 Many cities have poor heat emergency plans or none at all
 No specific standards exist that prescribe appropriate
preparedness & response actions
 An effective plan will reduce the impact of a heat wave on the
health of the affected population and must include:
◦ A phased approach that addresses the measures taken by each
agency leading up to the summer season
◦ A clearly defined role of each local agency
◦ A standard warning system that must emphasize & target
vulnerable populations
Preseason Community
Preparedness Activities
Workplace Heat Stress Prevention
 OSHA mandates that employers must
“furnish to each of his employees
employment & a place of employment
which are free from recognized hazards
that are causing or are likely to cause
death or serious physical harm”
 If you work in a hot environment, you
must be oriented before regular heat
exposure, which should include:
◦ A screening process to identify & quantify risk
factors
◦ A time must be established for acclimatization
of the body to the hot environment through
incremental exposures
 The basic steps needed for an effective response
to a heat wave begin with community planning &
personal preparedness
 Effective strategies should begin with the
formation of a local or regional Heat Wave Task
Force
 Building a heat wave resilient community
includes measures that reduce the possibility of
failure of critical infrastructures such as power
grids
 Reducing the health impact of heat on vulnerable
populations is best achieved through
communicating basic personal preparedness
measures & emphasizing actions taken to cool
down
Immediate Actions
 All the personal variables that may
influence your risk & plan for the warm
season need to be considered:
◦ Lighter colored clothes
◦ Loose-fitting, light weight clothing
◦ Plan activities that keep you in the shade or
prepare to wear a hat & use sunscreen with
a high SPF
◦ Simply slow down
◦ Avoid excessive exertion during peak
temperatures of the day
◦ Avoid heavy meals
Personal Actions
 The central focus of community heat wave
preparedness is identifying &
communicating with vulnerable
populations
 Each public & private organization
involved must clearly understand their
function before the emergency & be
prepared to quickly carry out their
assigned roles
 The media can assist in reaching a large
portion of vulnerable individuals
Community Actions
Heat
Wildfires
Chapter Thirteen
Wildfires
 Wildfires have always been part of the ecosystem
& are often natural occurrences started by
lightning strikes
 They are also sometimes manmade through
carelessness or intentional fire starting
 These fires thrive best in areas that have
vegetation, winds, & periods of dry weather
 These fires can naturally occur & actually have
long-term benefits for some ecosystems
 Human habitation near susceptible areas places
populations at risk for major public health,
economic, & environmental damage
 Wildfire smoke is a complex assortment of gases
& particles
 The obvious risks are burns & heat injuries, but
the most far-reaching & challenging health issue
is smoke
 The smoke produced by wildfires can produce
effects ranging from airway & eye irritation to
death
 The primary short-term inhalational challenges
are particles that irritate the airway & cause
symptoms even among healthy exposed
individuals, including coughing, wheezing, &
difficulty breathing
 Other smoke components have toxicity potential
as allergens, carcinogens, mutagens, &
teratogens
 The majority of the exposed population will not
experience long-term effects from wildfire smoke
Effects on the Human
Populations
 Preparing for wildfires begins with an
assessment of local risk & history of
wildfires in the region
 A long dry weather period can introduce the
risk of wildfires to areas with little or no
history
 A 30-foot safety zone around a home is
recommended to reduce the wildfire risks to
the structure
 The amount & type of vegetation in a zone
known to have wildfire risks should be
carefully considered
Prevention
 If there is a reasonable chance that a wildfire will
threaten human lives & property, evacuation
orders are issued
 The following precautions should be taken:
◦ If you are trapped in a stranded vehicle, it is usually
better to stay in the vehicle than to try & outrun the
advancing fire on foot
◦ If you are trapped inside a home or other structure, it is
best to remain inside long enough for the worst of the
wildfire to pass by
◦ If you are outside when fires approach, the best action is
to find the closest area with the least amount of
vegetation or fuel to burn
◦ The minimum protection against wildfire smoke is a
properly fitted N-95 respirator
Immediate Actions
 It is important to check the roofs & attics
of affected buildings for fires & embers
 For several hours after, there should be a
“fire watch” with regular monitoring for
signs of smoke & fire throughout nearby
structures
 The primary residual hazard is the fire ash
accumulation
Response & Recovery
Challenges
Arizona 2011
Volcanoes
Chapter Twelve
Volcanoes
 Volcanoes are responsible for the
formation of much of the Earth’s surface
 They are typically hills or mountains that
surround a vent leading to reservoirs of
molten rock below the Earth’s surface
 There are four primary types of
volcanoes:
◦
◦
◦
◦
Cinder Cone
Composite
Shield
Lava Dome
 The Volcanic Explosivity Index (VEI) is a
composite, semiquatitative estimate of a
volcano’s eruptive power
 During a volcanic eruption, there are a variety of
hazards produced:
◦ Gases and particles are rapidly ejected, reaching heights
of up to 10–20 miles and can literally be carried around
the planet
◦ Direct blasts and flows are projected laterally
◦ Large rocks and enormous volumes of materials can be
hurled at a high rate of speed for many miles
◦ Clouds of hot particles and gases that spill down the
slopes of a volcano (pyroclastic flows) may form
◦ Particles separate into layers of different charges
generating lightening similar to what is seen during
thunderstorms
◦ Downwind areas are covered with ash
◦ Lahars are often formed
Volcanoes (continued)
 Direct hazards include rocks, ash, gases,
and heat from an eruption
 Larger solid debris can cause ballistic
injuries for miles
 Gases can cause respiratory damage
 Pyroclastic flows and lava flows can cause
thermal injuries
 Carbon dioxide and debris from an eruption
can cause asphyxiation
 Other hazards result from secondary
events, including earthquakes, flooding,
landslides, lightening, and even tsunamis
Health Effects
 Preparedness measures for volcanoes begin with
a home preparedness kit and an understanding
of the risk for volcanic eruptions
 Unlike many other natural disaster threats that
are focused tightly on a specific geographic
region, volcanoes can reach hundreds of miles
downwind and cause severe interruption in
critical infrastructure
 Even if you are near a dormant volcano, you
should have a plan and be prepared to evacuate
quickly
 People should be encouraged to avoid active
volcanoes
 If you are close enough to observe a volcanic
eruption, you are in unnecessary danger
Prevention
 Ideally, there should be an evacuation order given and
everyone should evacuate from the area
 During evacuation, avoid areas downwind and avoid river
valleys downstream from the volcano
 If you are outside, seek inside shelter immediately
 Avoid low-lying areas where mudflows are possible
 Remember to help neighbors that may need assistance
 Bring all animals and livestock under cover in closed
shelters
 Put all machinery inside closed garages or barns
 Once indoors:
◦ Close all the windows, doors, fireplace dampers, etc.
◦ Close down your heating, ventilation, and air conditioning
◦ Place damp, rolled towels along base of the doors and anyplace
else where a draft may introduce ash into the building
Immediate Actions
 Local emergency management officials will
provide detailed instructions to area
residents
 If it is necessary to go outside, during or
immediately after the ash fall, cover your
mouth and nose to filter out the larger
particles and protect your respiratory tract
 All exposed skin should be covered
 Goggles should be worn when clearing the
roof of ash accumulation
 Outer clothing should be removed before
entering the building to limit the transport
of ash into the structure
Response and Recovery
Challenges
Chile 2011
Case Study-Climate Change and
Public Health (reference: Jonathan E. Fielding, MD, MPH, Public Health
Director and Health Officer Los Angeles County Department of Public Health )

It is our job to protect the public’s health

Fighting climate change is aligned with protecting and
promoting health
◦ WHO estimates that in the year 2000, there were 150,000 excess deaths
per year due to climate change
◦ Climate change is already affecting health around the world, and its
impact on health will continue to grow
◦ Many of the proposed solutions for climate change are healthy for
everyone

We have the appropriate skills
◦ Public Health has the skills to effect behavior change, and those skills
can help people adopt greener behaviors too
◦ Public Health has policy and advocacy skills that will help encourage
organizational and societal changes
Role of Public Health
Extreme weather and disease
 Effects
of rising sea level
• Coastal areas will become
vulnerable to storms and
flooding
• Loss of coastal wetlands
and erosion of beaches
• Saltwater contamination of
drinking water
• Potential damage to roads,
highways, and other
infrastructures near coastal
areas
Sea level rise
 Warmer
temperatures can
result in premature and
rapid snowmelt in the
Sierra snow pack, which
alters the timing of run-off
water supplies for ½ of
CA’s surface water
Severe flooding may

Drought risk may be
acutely elevated during the
summer months
occur during winter
and spring, with
slower water flow
during summer
seasons
Example California
 Los Angeles
projected to have an increase of 62% 88% in heat-related mortality by 2080
 Health impacts likely to be seen 1 to 3 days after the
onset of the heat waves
Health effects of extreme and prolonged heat exposure
include: heat cramps, heat exhaustion, heat stroke, heat
syncope (fainting)
 Devastating
heat waves seen elsewhere recently
5-day heat wave in Chicago in 1995: 700 excess deaths,
most attributed to the heat
August 2003 European heat wave: 35,000 excess deaths
Health Impacts of Heat Waves
 Greater
risk for people
who do not have access
to air conditioning
May not be able to afford
air conditioning
For populations
unaccustomed to heat
waves, people may have air
conditioning but chose not
to use it, not realizing
danger
 Two
vulnerable
populations during heat
waves:
Elderly: Population of
senior citizens (> 60 years
old) in Los Angeles County
is expected to increase by
83% by the year 2020
Low SES: Over 16% of
LA County residents under
100% FPL
Heat Waves: Vulnerable Populations
 Increased
temperature and increased carbon dioxide in atmosphere
leads to
Increase in formation of ground-level ozone (and smog)
Increased allergen production (e.g. pollen)
Longer seasons for allergen producing weeds
 Senior
citizens, children, and people with respiratory and chronic
diseases are most vulnerable to high levels of ozone and increased
allergens
 Health
effects of high levels of ozone exposure include:
Reduced lung function
Respiratory discomfort
Exacerbation of chronic respiratory illnesses
 Public
health already utilizes a multi-level prevention
approach – analogous approach can be taken to respond
to climate change
Primary prevention = climate change mitigation
Efforts to slow, stabilize, reverse climate change by reducing GHG
emissions
Efforts will occur in sectors other than PH, such as energy and
transportation
Secondary/tertiary prevention = climate change adaptation
Efforts to prepare for, and minimize health burden of, climate change
Similar to public health preparedness for other uncertainties (e.g.
pandemic flu, bioterrorist attack), so likely that PH as sector will be
involved in adaptation efforts
Public Health Response
Mitigation = reduce GHG emissions
Reduce energy usage and Reduce, Reuse, Recycle
1.
2.
As individuals, at home
As organizations, at work
Adaptation = prepare for impact of climate change
Emergency preparedness
1.
2.
As individuals/families
As local health department
Mitigation and adaptation = advocate for healthy
policies
1. Support legislation that reduces GHG emissions
2. Support sustainable lifestyles & communities
Actions
 We
need to prepare now for the inevitable effects of
climate change, such as heat waves and wildfires
Good news: preparing for one type of emergency prepares
us for all types of emergencies
Preparation minimizes impact of disasters and fear/anxiety
 We
need to prepare ourselves as individuals and as
health agencies
Preparation