A Guide for Public Health Officials
Revised 2019
-------
-------
EPA-452/R-19-901
August 2019
WILDFIRE SMOKE:
A GUIDE FOR PUBLIC
HEALTH OFFICIALS
-------
ACKNOWLEDGEMENTS
The Wildfire Smoke Guide for Public Health
Officials, first published in 2002, was developed in
part as a result of a workshop held at the University
of Washington in June 2001, under the auspices of
the U.S. Environmental Protection Agency, Region
X, and the Department of Environmental Health,
School of Public Health and Community Medicine
of the University of Washington. It was written
by Harriet Ammann (Washington Department
of Health); Robert Blaisdell and Michael Lipsett
(California Office of Environmental Health Hazard
Assessment), Susan Lyon Stone (U.S. Environmental
Protection Agency); and Shannon Therriault
(Missoula, MT County Health Department),
with input from individuals in several other state
and federal agencies, in particular Jed Waldman
(California Department of Health Services) and
Peggy Jenkins (California Air Resources Board).
The 2008 version of this document was written by
Michael Lipsett and Barbara Materna (California
Department of Public Health); Susan Lyon
Stone (U.S. Environmental Protection Agency);
Shannon Therriault (Missoula, MT County Health
Department); Robert Blaisdell (California Office
of Environmental Health Hazard Assessment); and
Jeff Cook (California Air Resources Board), with
input from individuals in several other government
agencies and academia.
The 2016 version of this document was updated
by a team of experts from the same agencies that
developed the current, 2019 version. The goal of the
2016 revision was to quickly update the 2008 version
by incorporating the expanded scientific evidence
base, and then take more time expanding the Guide
by adding new sections and fact sheets. Since 2016,
eight factsheets have been developed, with links
available in .Appendix A. More will be coming,
including translations of the currently available ones,
so watch for them.
This 2019 version of the Guide is the product
of an inter-agency collaboration that includes:
California Air Resources Board; California Office
of Environmental Health Hazard Assessment; U.S.
Centers for Disease Control and Prevention; U.S.
Forest Service; and U.S. Environmental Protection
Agency. Team members, authors, contributors and
reviewers are listed below.
For More Information
Project Lead: Susan Lyon Stone,
stofie.susati@eoa.PT)v
Chapter 1 Health Effects: Jason Sacks,
sacks.iason@epa.gov
Chapter 2 Air Quality Impacts: Peter Lahm,
peter.lahm@usda.pov
Chapter 3 Exposure Reduction Strategies: Alison
Clune, clutie.alisoti@cna.PT)v
Respirators: Lewis Radonovich, mto5@cdc.gov and
Maryann D'Alessandro, bni5@.cdc.p;ov
Chapter 4 Air Quality Communication: Miki
Wayland, wayland.michelle@epa.gov
Chapter 5 Public Health Actions: Maria Mirabelli,
zif7 @.cdc.P'Ov
Photos: Front cover, back cover, and Chapter 2 title
page courtesy of the U.S. Forest Service. Chapter
4 title page courtesy of Robert Elleman, U.S.
Environmental Protection Agency.
Disclaimer
The viewpoints and policies expressed herein do not
necessarily represent those of the various agencies
and organizations listed. Mention of any specific
product name is neither an endorsement nor a
recommendation for use.
ii
-------
TABLE OF CONTENTS
Team, Authors, Contributors, Reviewers viii
Executive Summary 1
Health Effects of Wildfire Smoke 1
Wildfire Smoke and Air Quality Impacts 1
Specific Strategies to Reduce Exposure to Wildfire Smoke 2
Communicating Air Quality Conditions during Smoke Events 2
Recommendations for Public Health Actions 3
I. Health Effects of Wildfire Smoke 4
At-risk lifestages and populations 6
Summary 9
II. Wildfire Smoke and Air Quality Impacts 11
Composition of wildfire smoke 12
Characteristics of wildfires 13
Wildland fuels 14
Meteorology and smoke 15
Wildland fire management 15
Incident Management Teams 16
III. Specific Strategies to Reduce Exposure to Wildfire Smoke 17
Stay indoors 18
Reduce activity 19
Reduce other sources of indoor air pollution 19
Use air conditioners and filters 19
Central air systems 20
Swamp coolers 21
Ductless mini-split systems 21
Window-mounted and portable air conditioners 22
Use room air cleaners 22
Choose an air cleaner appropriate for the size of the indoor environment 22
Choose an air cleaner that effectively removes particles without producing ozone 23
Place and operate the air cleaner to maximize particle removal 23
Air cleaners for gases and odors 23
Do-it-yourself box fan air cleaners 23
Avoid ozone generators 24
Humidifiers 24
Create a clean room at home 25
Cleaner air shelters and cleaner air spaces 25
iii
-------
Cleaner air shelters 25
Cleaner air spaces 25
Inside vehicles 26
Respiratory protection for wildfire smoke and ash 26
Children and respirator use 27
Who may need to wear a respirator 27
Choosing the correct respirator 28
How to use a tight-fitting respirator 28
Possible risks from wearing a respirator 28
Certain "masks" do not provide protection 29
Handling respirator shortages 29
Respiratory protection resources 29
Avoiding smoky periods 30
Closures 30
Evacuation 30
Summary of strategies to reduce smoke exposure 31
IV. Communicating Air Quality Conditions during Smoke Events 32
Air Quality Index 33
AirNow 33
Interagency Wildland Fire Air Quality Response Program and Air Resource Advisors 35
New monitoring and air quality estimation technologies a caution 36
Using visual range to assess smoke levels in the interior western United States 37
Basic Approach: 37
V. Recommendations for Public Health Actions 39
Public advisories and protective measures 40
Protecting children 40
Protecting other at-risk groups 41
Protecting outdoor workers 41
Prolonged smoke events 42
Protecting pets and livestock 43
Air quality cautionary statements and recommended public actions 43
Public service announcements 47
General recommendations to the public 47
Recommendations for people with chronic diseases 48
Use social media to raise awareness 48
Preparedness 49
Recommended steps for public health officials before fire season 49
Build strong partnerships 50
Putting together a wildfire smoke team 50
Cleaning up after the fire 51
iv
-------
References 53
Additional Resources and Links 56
Active Wildfire Information 56
Satellite Images of Fires and Smoke 56
Weather 56
Information about Wildfire Smoke and Health Effects 56
Appendix A A-l
Available Factsheets as of March 2019 A-l
Appendix B B-l
Identification and Preparation of Cleaner Air Shelters for Protection of the Public
from Wildfire Smoke B-l
Appendix C C-l
Technical Wildfire and Smoke Resources C-l
Accessing Information about Active Wildfires C-l
Seeing Smoke from Space C-2
AirNow-Tech C-2
U.S. Forest Service/Interagency Wildland Fire Air Quality Response Program Tools C-3
Particulate (PM2 5) Monitoring Website Tool C-3
BlueSky Daily Smoke Model Runs C-5
Appendix D D-l
Guidance on Protecting Workers in Offices and Similar Indoor Workplaces from
Wildfire Smoke D-l
Using the HVAC System(s) to Protect Building Occupants from Smoke D-l
Other Actions to Protect Employees from Wildfire Smoke D-2
Additional Information D-2
Appendix E E-l
Hazards during Cleanup Work Following Wildfires from National Institute
for Occupational Safety and Health E-l
v
-------
LIST OF FIGURES
Figure 1. Fine, inhalable particulate matter (PM2 5) is the air pollutant of greatest concern to public
health from wildfire smoke because it can travel deep into the lungs and may even enter the
bloodstream 12
Figure 2. Wildfire rate of spread, fuel consumed, smoke produced, and duration are all influenced by
vegetation type 13
Figure 3. Strong winds can cause rapid fire spread and move smoke into communities far from a wildfire.14
Figure 4. Two types of N95 disposable particulate respirators. Note the presence and placement of the two
straps above and below the ears 27
Figure 5. A one-strap paper mask is not a respirator and provides little or no protection from smoke
particles. Photo courtesy of the California Department of Public Health 29
Figure 6. A surgical mask is designed to capture infectious particles generated by the wearer, is not a
respirator, and provides little or no protection from smoke particles 29
Figure 7. Overall concept of the NowCast 33
Figure 8. Sample AirNow current air quality data, map, and AQI values 34
Figure 9. Sample AirNow Fires: Current Conditions map 34
Figure 10. Elements of the Wildland Fire Air Quality Response Program supporting an Air Resource
Advisor assigned to an Incident Management Team responding to a wildfire 35
Figure 11. Example smoke outlook (partially shown) produced by an Air Resource Advisor assigned to the
416 Fire 36
Figure CI. Smoke from many large fires creating haze across the western and central United States. Red dots
are satellite fire hot spot detections C-l
Figure C2. Smoke plumes from NOAA Hazard Mapping System. See more about the NOAA HMS here:
https://www.ospo.tioaa.gov/Prodiicts/latid/hms.htnil C-2
Figure C3. AirNow-Tech Navigator C-2
Figure C4. PM25 monitoring web tool display example. Current fine particulate NowCast conditions are
shown on the map C-3
Figure C5. BlueSky daily smoke model run for the Continental United States (CONUS) shown in the web
viewer version C-4
Figure C6. BlueSky hourly average surface smoke predictions at lam on 8/19/2018 at 3 grid resolutions: (a)
1.33 km, (b) 4 km, and (c) 12 km in north central Washington C-4
vi
-------
LIST OF TABLES
Table 1. Summary of lifestages and populations potentially at-risk of health effects from wildfire smoke
exposures 10
Table 2. Particle size efficiency for select MERV ratings 21
Table 3. Visual range and actions to take to reduce smoke exposure when wildfire smoke is in the air 38
Table 4. Health effects and cautionary messages for at risk populations for each
AQI category 44
Table 5. Recommended actions for consideration by public health officials 46
vii
-------
TEAM,AUTHORS, CONTRIBUTORS,
REVIEWERS
Team Members
Susan Lyon Stone MS, Senior Environmental
Health Scientist, Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711. Project Lead
Martha Berger MPA, Program Analyst, Office of
Children's Health Protection, U.S. Environmental
Protection Agency, Washington, DC, 20460.
Cory R. Butler MS, Occupational Safety and Health
Specialist, Western States Division, National Institute
for Occupational Safety and Health, U.S. Centers for
Disease Control and Prevention, CO 80215.
Wayne E. Cascio MD, Director, National Health and
Environmental Effects Research Laboratory, U.S.
Environmental Protection Agency, Research Triangle
Park, NC 27711.
Alison Clune MPH, Biologist, Office of Radiation
and Indoor Air, U.S. Environmental Protection
Agency, Washington, DC, 20460.
Scott Damon MAIA, Health Communication Lead,
Asthma and Community Health Branch, National
Center for Environmental Health, U.S. Centers for
Disease Control and Prevention, Atlanta, GA 30341.
Phillip G. Dickerson BS CPE, Supervisory
Environmental Protection Specialist, Office of Air
Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, NC
27711.
Paul Garbe DVM, Retired, Air Pollution and
Respiratory Health Branch, National Center for
Environmental Health, U.S. Centers for Disease
Control and Prevention, Atlanta, GA 30341.
William E. Haskell MS, Retired, National Personal
Protective Technology Laboratory, National Institute
for Occupational Safety and Health, U.S. Centers for
Disease Control and Prevention, MA 01810.
Sumi Hoshiko MPH, Research Scientist,
Environmental Health Investigations Branch,
California Department of Public Health, Richmond,
CA 94804.
Ali Kamal PhD, Physical Scientist, Office of Air
Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, NC
27711.
Peter Lahm MEM, Air Resource Specialist, Fire
& Aviation Management, U.S. Forest Service,
Washington, DC 20250.
Barbara Materna PhD, CIH, Chief, Occupational
Health Branch, California Department of Public
Health, Richmond, CA 94804.
Maria C. Mirabelli PhD, MPH, Senior Service Fellow,
Asthma and Community Health Branch, National
Center for Environmental Health, U.S. Centers for
Disease Control and Prevention, Atlanta, GA 30341
Tracey Mitchell RRT, AE-C, Environmental
Protection Specialist, Office of Radiation and
Indoor Air, U.S. Environmental Protection Agency,
Washington, DC, 20460.
Karen Riveles PhD, MPH, Staff Toxicologist
& Emergency Response Coordinator, Office
of Environmental Health Hazard Assessment,
California Environmental Protection Agency,
Sacramento, CA 95812.
Jason Sacks MPH, Epidemiologist, National Center
for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC
27711.
Michelle Wayland BSE, Environmental Engineer,
Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Research Triangle
Park, NC 27711.
viii
-------
John E. White BSM, Environmental Protection
Specialist, Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711.
Jeffery R. Williams PhD, Air Pollution Specialist,
Research Division, California Air Resources Board,
Sacramento, CA 95812.
Authors
Susan Lyon Stone MS, Senior Environmental
Health Scientist, Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711. Project Lead,
health, health communication, public health policy.
Laura Anderko PhD, RN, Director, Mid-Atlantic
Center for Children's Health and the Environment,
School of Nursing and Health Studies, Georgetown
University, Washington DC 20057. Children's health.
Martha Berger MPA, Program Analyst, Office of
Children's Health Protection, U.S. Environmental
Protection Agency, Washington, DC, 20460.
Children's health.
Cory R. Butler MS, Occupational Safety and Health
Specialist, Western States Division, National Institute
for Occupational Safety and Health, U.S. Centers
for Disease Control and Prevention, CO 80215.
Occupational health.
Wayne E. Cascio MD, Director, National Health and
Environmental Effects Research Laboratory, U.S.
Environmental Protection Agency, Research Triangle
Park, NC 27711. Health, health research.
Alison Clune MPH, Biologist, Office of Radiation
and Indoor Air, U.S. Environmental Protection
Agency, Washington, DC, 20460. Indoor air quality,
filtration, air cleaning.
Scott Damon MAIA, Health Communication Lead,
Asthma and Community Health Branch, National
Center for Environmental Health, U.S. Centers for
Disease Control and Prevention, Atlanta, GA 30341.
Health communication.
Paul Garbe DVM, Retired, Air Pollution and
Respiratory Health Branch, U.S. Centers for Disease
Control and Prevention, Atlanta, GA 30341. Health,
epidemiology.
Maris sa Hauptman MD, MPH, Pediatric
Environmental Health Fellow, New England
Pediatric Environmental Health Specialty Unit,
Boston Children's Hospital, Boston, MA 02115.
Children's health.
William E. Haskell MS, Retired, National Personal
Protective Technology Laboratory, National Institute
for Occupational Safety and Health, U.S. Centers for
Disease Control and Prevention, MA 01810. Personal
protective technology.
Sumi Hoshiko MPH, Research Scientist,
Environmental Health Investigations Branch,
California Department of Public Health, Richmond,
CA 94804. Health, epidemiology.
Peter Lahm MEM, Air Resource Specialist, Fire
& Aviation Management, U.S. Forest Service,
Washington, DC 20250. Chapter 2 lead, air quality,
smoke emissions, smoke forecasting, smoke
management.
Barbara Materna PhD, CIH, Chief, Occupational
Health Branch, California Department of Public
Health, Richmond, CA 94804. Occupational health,
respirators.
Maria C. Mirabelli PhD, MPH, Senior Service Fellow,
Asthma and Community Health Branch, National
Center for Environmental Health, U.S. Centers for
Disease Control and Prevention, Atlanta, GA 30341.
Chapter 5 Lead, health, epidemiology.
Narasimhan (Sim) Larkin PhD, Climate Scientist, Air
Fire Team, U.S. Forest Service, Pacific Northwest
Fire Station, WA 98103. Air quality, smoke emissions,
smoke forecasting.
Susan O'Neill PhD, Research Air Quality Engineer,
AirFire Team, U.S. Forest Service, Pacific Northwest
Fire Station, WA 98103. Air quality, smoke emissions,
smoke forecasting.
Janice Peterson MS, Air Resource Specialist,
U.S. Forest Service, Pacific NW Region, Seattle,
WA 98103. Air quality, smoke emissions, smoke
forecasting.
ix
-------
Karen Riveles PhD, MPH, Staff Toxicologist
& Emergency Response Coordinator, Office
of Environmental Health Hazard Assessment,
California Environmental Protection Agency,
Sacramento, CA 95812. Smoke, ash, school closure,
toxic air contaminants, risk communication.
Jason Sacks MPH, Epidemiologist, National Center
for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC
27711. Chapter 1 Lead, health, epidemiology.
Michelle Wayland BSME, Environmental Engineer,
Office of Air Quality Planning and Standards,
U.S. Environmental Protection Agency, Research
Triangle Park, NC 27711. Chapter 4 Lead, air quality
communication.
Jeffery R. Williams PhD, Air Pollution Specialist,
Research Division, California Air Resources Board,
Sacramento, CA 95812. Chapter 3 Lead, indoor air,
filtration, portable air cleaners, personal exposure,
asthma, cleaner air shelters, ozone.
Contributors
Ann R. Brown BA, Communications Lead Air and
Energy National Research Program, National Health
and Environmental Exposure Research Laboratory,
U.S. Environmental Protection Agency, Research
Triangle Park, NC 27711.
Sarah Coefield MS, MA, Air Quality Specialist,
Missoula City-County Health Department, Missoula,
MT 59802.
Maryann M. D'Alessandro PhD, Director, National
Personal Protective Technology Laboratory, National
Institute for Occupational Safety and Health,
Pittsburgh, PA 15236.
Gayle S.W Hagler, PhD, Environmental Engineer,
Office of Research and Development, U.S.
Environmental Protection Agency, Research Triangle
Park, NC 27709.
Laura Kolb, Office of Radiation and Indoor Air,
Indoor Environments Division, U.S. Environmental
Protection Agency, Washington, DC, 20460.
Lewis Radonovich MD, Chief of Research, National
Personal Protective Technology Laboratory, National
Institute for Occupational Safety and Health,
U.S. Centers for Disease Control and Prevention,
Pittsburgh, PA 15236.
Reviewers
California Air Resources Board: Peggy L. Jenkins;
Lori Miyasato, PhD; Hye-Youn Park, PhD; Charles
Pearson; Feng-Chaio Su, PhD; Barbara Weller, PhD;
California Department of Industrial Relations,
Division of Occupational Safety and Health:
Eric Berg MPH; Amalia Niedhardt MPH.
California Office of Environmental Health Hazard
Assessment: Rupa Basu, PhD, MPH; Heather
Bolstad, PhD; Dharshani Pearson, MPH; Xiangmei
Wu, PhD.
U.S. Centers for Disease Control and Prevention:
Josephine Malilay PhD, MPH; Kanta Sircar PhD,
MPH.
U.S. Environmental Protection Agency: Kirk Baker
PhD; Pat Dolwick MS; Janice Dye DVM; Michael
P. Firestone PhD; Benjamin Gibson MPP; Joanna
Gmyr MEM; Elizabeth D. Hilborn DVM, MPH,
Dipl. ACVPM; Stacey Katz MPH; Laura Kolb; Gail
Robarge; Karen Wesson MS.
U.S. Forest Service: Melanie Pitrolo MS; Leland
Tarnay PhD.
U.S. National Park Service: Mark Fitch MS.
x
-------
SUMMARY
Wildfire smoke events can occur without warning
but we can be prepared. This Guide is intended
to provide state, tribal, and local public health
officials with information they need to be prepared
for smoke events and, when wildfire smoke is
present, to communicate health risks and take
measures to protect the public. Although developed
for public health officials, the information in this
document could be useful to many other groups
including health professionals, air quality officials,
and members of the public. The document is
divided into five Chapters and five Appendices.
Guide authors and contributors will post up-to-date
guidance, documents, and other new evidence-based
information here between revisions for use by public
health officials.
Health Effects ofWildfire Smoke
Wildfire smoke is a mixture of air pollutants of
which particulate matter is the principal public
health threat. The initial basis for understanding
wildfire smoke health effects was derived primarily
from studies of ambient air pollutants, specifically
particulate matter. Extensive scientific evidence has
demonstrated health effects in response to short-
term (i.e., daily) particulate matter exposure ranging
from eye and respiratory tract irritation to more
serious effects, including reduced lung function,
pulmonary inflammation, bronchitis, exacerbation
of asthma and other lung diseases, exacerbation of
cardiovascular diseases, such as heart failure, and
even premature death. Recent studies examining the
health effects of wildfire smoke provide evidence
of health effects consistent with those reported for
particulate matter. However, there is only limited
evidence about the potential health impacts due
to cumulative exposures from repeated, multi-day
wildfire smoke exposures or multiple, consecutive
fire seasons.
Although a large population can be exposed to
smoke during a wildfire event, most healthy adults
and children will recover quickly from wildfire
smoke exposure. Certain lifestages and populations
may, however, be at greater risk of experiencing
health effects, including people with respiratory or
cardiovascular diseases, children and older adults,
pregnant women, people of lower socioeconomic
status, and outdoor workers.
Wildfire Smoke arid Air Quality Impacts
The science of wildfire behavior and management
is complex and highly technical. Wildfire smoke
produced from combustion of natural biomass
contains thousands of individual compounds,
including particulate matter, carbon dioxide, water
vapor, carbon monoxide, hydrocarbons and other
organic chemicals, nitrogen oxides, and trace
minerals. Wildfires can move into the wildland urban
interface (WUI), burning homes and structures and
thereby consuming man made materials in addition to
natural fuels. More research is needed to understand
potential health impacts of breathing this complex
mix of natural and man made material emissions.
Wildfire behavior will vary depending on natural
fuel type; fires in forest fuels can range from mild
to severe and can spread very slowly or extremely
rapidly depending on weather and fuel conditions.
Wildfires in forests can last for weeks or months and
are often the type that results in the most severe and
longest duration air quality impacts. Smoke levels in
populated areas can be difficult to predict.
Most of the tens of thousands of wildfires in the
United States are suppressed when they first start.
Those that continue past the initial suppression
attempt can become large, of long duration, and a
significant source of smoke. On these types of fires,
an Incident Management Team (IMT) is usually
1
-------
engaged, which is then guided by the land owner/
manager/agency administrator and pre-existing land
management plans.
Specific Strategies to Reduce Exposure
to Wildfire Smoke
In areas where the public is experiencing wildfire
smoke, public health and air quality agencies should
provide advice on strategies to limit exposure, which
include staying indoors; limiting physical activity;
reducing indoor air pollution sources; effectively
using air conditioners and air filters or cleaners;
creating cleaner air shelters; and using respiratory
protection appropriately.
The most common advisory during a smoke episode
is to stay indoors, where people can better control
their environment. Whether at home or in a public
space, indoor environments that have filtered air
and climate control can provide relief from smoke
and heat. High-efficiency heating, ventilation, and
air-conditioning (HYAC) filters (rated MERV 13 or
higher) in systems that can accommodate them can
help reduce particle concentrations indoors.
Appropriately sized room air cleaners can also reduce
particle concentrations in individual rooms. It is
important to choose a room air cleaner that produces
little or no ozone. The California .Air Resources
Board provides a list of air cleaners that meet the
ozone emissions limit. High-efficiency filters and
room air cleaners are more effective with more
frequent operation. Individuals can use a room air
cleaner in a designated room in the house to create
a protected environment called a "clean room" at
home. Public cleaner-air shelters and spaces can
provide relief from smoke for individuals who do
not have adequate air filtration or cooling equipment
at home. When traveling between indoor locations
with cleaner air, people can reduce particle levels in
vehicles by keeping windows and vents closed and
operating the air conditioning in "recirculate" mode.
Properly wearing a NIOSH-certified N95 or PI00
particulate respirator that fits closely to the face can
help reduce personal exposure to wildfire smoke and
ash. Adults who must remain outdoors in unhealthy
air for extended periods due to work or other factors
may particularly benefit from using this strategy.
People should avoid using masks that do not provide
proper protection, such as single-strap dust masks
or surgical masks. Respirators are not made to fit
children and will not protect them from breathing
wildfire smoke.
Smoke levels can vary throughout the day, so people
may be able to plan necessary trips outside during
times when the air is less smoky or minimize their
time in smoke impacted areas. Smoke outreach and
forecasting tools can help people make decisions
about when and where they can go to minimize their
smoke exposures. When smoke levels are especially
high, local officials may take actions such as closing
schools or canceling public events. Where evacuation
is necessary because of fire danger, public health
officials should consider appropriate strategies to
reduce smoke exposure during the evacuation, at
evacuation centers, and after allowing evacuees to
return home.
Communicating Air Quality Conditions
during Smoke Events
The goal of air quality monitoring during a wildfire
smoke event is to relay information to the public in
a timely manner so people can make decisions about
how to protect their health. Tools for measuring and
estimating air quality conditions and conveying them
to the public include the .Air Oualitv Index (AQI;
available on AirNow). visual range scale, or other
approaches. The Current Conditions .Map provides
a one-stop place for the public on current wildfire
and air quality information. School-focused guidance
addresses outdoor activities, and the .Air Quality
Flap; Program uses a visual flag alert for schools
and organizations to take health protective actions.
When requested by the land manager responding
to a large wildfire, the I ti terage ticy Wi Id land Ft re
2
-------
.Air Quality Response Program will deploy an Air
Resource Advisor (ARA) to the IMT. These technical
specialists are trained to monitor air quality, analyze
smoke impacts, model future smoke impacts, and
provide smoke outlooks for impacted communities
which will help public health officials in advising the
public.
Areas without continuous PM monitors may be able
to get temporary, portable monitors through their
federal, state, tribal, or local air quality agencies or
the U.S. Forest Service, especially when associated
with a wildfire incident with an assigned ARA.
Emerging technology has expanded sources for air
quality information, including miniaturized PM2
sensors, mobile air quality monitoring systems, and
data fusion products. However, there are many
unknowns regarding their precision, accuracy, and
reliability, especially under wildfire conditions.
Therefore, sensor data and data fusion products
should be considered supplemental information, but
they need to be put into context with the help of
nearby regulatory monitors or short-term monitors,
AQI estimates, satellite data, and daily ARA Smoke
Outlooks.
Recommendations for Public
Health Actions
Communications planning for recommendations
should address not only messages and actions during
a wildfire event, but preparations to make before fires
occur and as well as guidance for cleaning up after
a fire. Many factors must be considered, so these
recommendations should be adapted to each specific
situation. Areas with established air quality programs
typically have a communication plan for wildfire
smoke events. One approach used by states and most
communities across the country is to refer the public
to the AitN ow website (www.a t r ti ow. g o v).
In areas where fires are likely to occur, state and
local public health agencies should consider
running pre-season PSAs or news and social media
announcements to advise the public on preparing
for the fire season. During smoke periods, public
advisories based on air quality levels should address
special needs of at-risk lifestages and populations (in
the Air Quality Index, the term "sensitive groups"
is used), including people with heart or lung disease,
older adults, children, pregnant women, and people
of lower SES. Other concerns include advisories
for outdoor workers, prolonged smoke events, and
protections for pets and livestock.
Preparation is key. Recommendations to the
public at risk for smoke exposure include advising
preparations in advance of wildfire season, e.g.
maintaining nonperishable groceries not requiring
cooking. People with chronic diseases should check
with their health care provider about precautions
ahead of smoke events and have an adequate supply
of medication available; asthmatics should have a
written asthma action plan.
Recommended steps for public health officials
to take before fires start include: check fire risk
in monthly outlooks at National Interagency Fire
Center (NIFC) website and, especially if high,
communicate risk to the public; consider how
to implement the recommended actions in the
Guide; prepare a communication plan; and form
partnerships with important partners or stakeholders
(e.g., air quality agencies, local health providers, the
media).
Even after the worst of the fire and smoke is over,
exposure to lingering smoke and ash from a wildfire
can cause significant health effects in both healthy
and at-risk populations, such as respiratory irritation,
heat-related illness and emotional stress, as well as
physical stress or injuries from cleanup activities. In
post-fire situations in which air quality is poor due to
smoke and ash residue in or near affected structures,
ventilation and other protective measures are advised
during cleanup.
3
-------
I. HEALTH EFFECTS
OF WILDFIRE SMOKE
generated from wildfire smoke are more, or less,
toxic than particles emitted from other sources
(US. EPA 2009; DeElorio-Barker et al. 2019). The
effects of particulate matter exposure range from
eye and respiratory tract irritation to more serious
disorders including reduced lung function, bronchitis,
exacerbation of asthma, heart failure, and premature
death. Short-term exposures (i.e., days to weeks)
to fine particles, a major component of smoke, are
associated with increased risk of premature mortality
and aggravation of pre-existing respiratory and
cardiovascular disease. In addition, fine particles
are respiratory irritants, and exposures to high
concentrations can cause persistent cough, phlegm,
wheezing, and difficulty breathing. Exposures to
fine particles can also affect healthy people, causing
respiratory symptoms, transient reductions in lung
function, and pulmonary inflammation. Particulate
matter may also affect the body's ability to remove
inhaled foreign materials, such as pollen and bacteria,
from the lungs. Specific lifestages and populations
may potentially be at increased risk of health effects
Wildfires expose populations to multiple
environmental hazards, from combustion
due to the fire itself to air pollution from
smoke and byproducts of combustion
such as ash. In addition, when wildfires
move into communities, chemicals
in plastics and other chemicals can
be released into the air from burning
structures and furnishings. Wildfires
also cause mental health concerns
and psychological stress. Recently,
epidemiological (e.g., Reid etal. 2016,
Tinling et al. 2016, Wettstein et al. 2018)
and toxicological (e.g., Kim et al. 2018)
studies have focused broadly on the
health effects of wildfire smoke exposure
and the toxicity of specific fuel sources,
respectively. These studies consistently
demonstrate a variety of respiratory-
related health effects with more recent studies also
providing some evidence of cardiovascular-related
health effects in response to short-term (i.e., daily)
wildfire smoke exposures. Although the body of
literature specifically examining the health effects
attributed to wildfire smoke exposure has grown, the
initial understanding of potential health effects was
derived from studies focusing on components of
ambient air pollution, primarily in urban settings, that
are also found in wildfire smoke (e.g., fine particulate
matter and carbon monoxide).
Particulate matter is the principal public health
threat from short-ami longer-term exposure to
wildfire smoke and is the focus of most of this
document. While particles from wildfire smoke can
vary in size (see Section II. Wildfire Smoke and
Air Quality Impacts), approximately 90% of total
particle mass emitted from wildfires consists of fine
particles (i.e., PM,5, particles 2.5 um in diameter or
smaller) (Vicente et al. 2013; Groj3 et al. 2013). The
scientific evidence does not indicate that particles
4
-------
due to particulate matter exposure (see next section)
and actions should be taken to reduce their exposure
to wildfire smoke.
Ground-level ozone, though less of a concern from
wildfires than particulate matter, can cause effects
such as reductions in lung function, inflammation
of the airways, chest pain, coughing, wheezing,
and shortness of breath even in healthy people.
These effects can be more serious in people with
asthma and other lung diseases. Respiratory effects
attributed to ozone exposure can lead to increased
use of medication, school absences, respiratory-
related hospital admissions, and emergency room
visits for asthma and chronic obstructive pulmonary
disease (COPD). Although the evidence of ozone's
effects on the cardiovascular system (the heart,
blood, and blood vessels) is more limited than the
evidence of effects on the respiratory system, it
indicates that short-term exposure to ozone may
cause effects such as changes in heart rate variability
and systemic inflammation. Additionally, evidence
indicates that short-term ozone exposures can lead
to premature mortality, as demonstrated by recent
epidemiologic studies that consistently report positive
associations between short-term ozone exposures
and total non-accidental mortality, which includes
deaths from respiratory and cardiovascular causes
(U.S. EPA, 2013).
Carbon monoxide is also present in wildfire smoke.
Typically, exposures to carbon monoxide from
wildfire smoke do not pose a significant hazard to
the public, except to some at-risk populations and
firefighters very close to the fire line. This is because
carbon monoxide does not travel far from the
point of combustion. Carbon monoxide enters the
bloodstream through the lungs and reduces oxygen
delivery to the body's organs and tissues. People
with cardiovascular disease may experience health
effects such as chest pain or cardiac arrhythmias
from lower levels of carbon monoxide than healthy
people. At higher levels (such as those that occur in
major structural fires), carbon monoxide exposure
can cause headache, weakness, dizziness, confusion,
nausea, disorientation, visual impairment, coma, and
death, even in otherwise healthy individuals.
Wildfire smoke also contains significant quantities
of respiratory irritants that can act in concert to
produce eye and respiratory irritation and potentially
exacerbate asthma. Additionally, Hazardous Air
Pollutants (HAPs) (also referred to as Toxic
Air Contaminants [TACs] by the California
Environmental Protection Agency [CalEPA]) are also
present in wildfire smoke (Reinhardt and Ottmar,
2010). HAPs may contribute to adverse health
effects in infants, children, pregnant women and
their fetuses, elderly persons, those with existing
lung, heart, or liver diseases, and persons engaging
in physical activity. Among the extensive list of
HAPs, acetaldehyde, acrolein, formaldehyde and
benzene, are of concern because of their differential
impact on infants and children compared to adults.
These HAPs overall contribute to the cumulative
irritant properties of smoke and are present in
concentrations that may be above regulatory health
guidance values (e.g. ;retice Exposure
Levels and US. EPA. Reference ( Concentrations).
While most of the focus on health effects of wildfire
smoke is on those attributed to short-term exposures
(i.e. over a few days to weeks), it is also important to
consider the health effects people may experience
from cumulative exposures, whether due to repeated,
multi-day exposures or multiple consecutive fire
seasons. For example, there is concern that long-term
exposures to chemicals in wildfire smoke at sufficient
concentrations and durations might be a contributor
to overall lifetime risk for heart disease, lung disease,
and cancer. Unfortunately, there is little information
on potential health effects from these types of
exposures. The limited number of epidemiologic
studies that have specifically examined the cumulative
effect of wildfire smoke exposure on health have
been studies of wildland firefighters. There is initial
evidence that continuous occupational wildland fire
smoke exposure (i.e., over multiple days) may have a
cumulative effect on lung function, with some studies
observing a progressive decline during burn seasons.
However, it is unclear if this decline persists across
off-seasons and it is difficult to compare a wildland
5
-------
firefighter's occupational exposure and resulting
health effects to those experienced by the general
population (Adetona et al. 2016).
Overall, it is important to recognize that not
everyone who is exposed to smoke from wildfires
will experience health effects. The level and
duration of exposure, age, individual susceptibility,
including the presence or absence of pre-existing
lung (e.g., asthma, COPD) or heart disease, and
other factors play significant roles in determining
whether someone will experience smoke-related
health problems.
At-risk lifestages arid populations
Most healthy adults and children will recover quickly
from smoke exposure and will not experience long-
term health consequences. However, certain at-risk
lifestages and populations may be at greater risk of
experiencing severe acute and chronic symptoms
(See Chapter 5 for strategies to reduce exposure for
at-risk lifestages and populations). Key risk factors
that shape whether a population or individual is at
increased risk of health effects from wildfire smoke
have been identified primarily from epidemiologic
studies examining exposure to fine particulate matter
in urban settings. These studies provide evidence
indicating the risk of health effects due to fine
particulate exposures can vary based on lifestage
(i.e., children, <18 years of age; and older adults, >
65 years of age), health status, and socioeconomic
status. However, studies suggest that the health
effects due to wildfire smoke exposure are likely to be
similar to those of urban particle pollution (Adetona
et al. 2016, Liu et al. 2015, Naeher et al. 2007, Reid et
al. 2016).
It appears that the risk of fine particle-related health
effects varies throughout a lifetime, generally being
higher during early childhood, lower in healthy
adolescents and younger adults, and increasing
during middle age through old age as the incidence
of heart and lung disease, hypertension, and diabetes
increases. Therefore, certain lifestages (e.g., children)
and populations (e.g., people with pre-existing
respiratory and cardiovascular disease) should be
particularly diligent about taking precautions to limit
exposure to wildfire smoke. The following sections
provide more specific information on subsets of
the population that may be differentially affected by
exposure to wildfire smoke.
While the focus of this section is on those groups
at greatest risk of experiencing health effects from
exposure to fine particles, as noted previously,
pollutants emitted from wildfires can undergo
atmospheric reactions and form secondary pollutants,
such as ozone. Some of the same groups that
are at increased risk of health effects due to fine
particles are also at increased risk of health effects
from exposure to ozone. This includes people
with asthma and other lung diseases, children,
older adults, and people who are active outdoors
(e.g., outdoor workers).
Therefore, the lifestages and population groups
considered as being at greatest risk of a health effect
from exposure to fine particles and ozone should
be aware of the potential effect of these pollutants
on their health during wildfire events by checking
the .Air Quality Index (API) forecast each day and
following recommendations to reduce fine particle
and ozone exposure.
People with asthma and other respiratory diseases.
More than 25 million people in the United States,
including more than 6 million children, experience
chronic lung diseases such as asthma with another
16 million experiencing CPPD (CDC 2017, CDC
2018). Air pollution, such as wildfire smoke, can lead
to breathing difficulties for people with chronic lung
diseases, such as asthma and CPPD, and potentially
trigger exacerbations of their disease. Extensive
evidence from epidemiologic studies focusing on
exposure to fine particles demonstrates increased
risk of emergency department visits and hospital
admissions for asthma and CPPD (U.S. EPA, 2009).
Asthma is a condition characterized by chronic
inflammation of the bronchi and smaller airways,
with intermittent airway constriction, causing
6
-------
shortness of breath, wheezing, chest tightness, and
coughing, sometimes accompanied by excess mucus
production. During an asthma attack, the muscles
tighten around the airways and the lining of the
airways becomes inflamed and swollen, constricting
the free flow of air. Because children's airways are
narrower than those of adults, irritation, such as from
wildfire smoke, that might create minor problems
for an adult may result in significant obstruction in
the airways of a young child. Additionally, minority
and impoverished children and adults bear a
disproportionate burden associated with asthma and
other diseases, which may increase their susceptibility
to the health effects of wildfire smoke (Brim et al.
2008, CDC 2014). However, these diseases affect all
age and sociodemographic groups.
A significant fraction of the population may
have airway hyper responsiveness; an exaggerated
tendency of the large and small airways (bronchi and
bronchioles, respectively) to constrict in response to
respiratory irritants including cold air, dry air, and
other stimuli, including wildfire smoke. While airway
hyper responsiveness is considered a hallmark of
asthma, this tendency may also be found in many
individuals without asthma for example, during
and following a lower respiratory tract infection. In
such individuals, wildfire smoke exposure may cause
asthma-like symptoms.
Individuals with COPD generally considered to
encompass emphysema and chronic bronchitis
may also experience worsening of their conditions
because of exposure to wildfire smoke. Patients with
COPD often have an asthmatic component to their
condition, which may result in their experiencing
asthma-like symptoms. However, because their lung
capacity has typically been seriously compromised,
additional constriction of the airways in individuals
with COPD may result in symptoms requiring
medical attention. Researchers have reported that
individuals with COPD run an increased risk of
requiring emergency medical care after exposure to
particulate matter or wildfire smoke. In addition,
because COPD is usually the result of many years
of smoking, individuals with this condition may also
have heart and vascular disease and are potentially at
risk of health effects due to wildfire smoke exposure
from both conditions.
People with cardiovascular disease. Cardiovascular
diseases are the leading cause of mortality in the
United States, comprising approximately 30 to 40
percent of all deaths each year (Xu et al. 2018).
Most of these deaths occur in people over 65 years
of age. Diseases of the circulatory system (e.g.,
high blood pressure, heart failure, vascular diseases
such as coronary artery disease, and cerebrovascular
conditions) can put individuals at increased risk
of cardiovascular-related events triggered by
air pollutants.
Following exposure to particulate matter, people with
chronic heart disease may experience one or more
of the following symptoms: palpitations, unusual
fatigue, or lightheadedness; shortness of breath,
chest tightness, pain in the chest, neck, or shoulder.
Chemical messengers released into the blood because
of particle-related lung inflammation may increase
the risk of blood clot formation, angina episodes,
heart attacks, and strokes. Studies have linked fine
particulate matter to increased risks of heart attacks,
and sudden death from cardiac arrhythmia, heart
failure, or stroke (U.S. EPA, 2009). Despite this
evidence regarding fine particulate matter effects and
cardiovascular effects, wildfire-related cardiovascular
studies have been inconsistent, although several
recent investigations have identified elevated risks
of specific health outcomes (Wettstein et al. 2018,
Deflorio-Barker et al. 2019).
Children. All children, even those without
pre-existing illnesses or chronic conditions, are
considered at-risk of experiencing a health effect due
to air pollution, including wildfire smoke. Compared
to adults, children spend more time outside, tend to
engage in more vigorous activity, and inhale more
air (and therefore more smoke constituents) per
pound of body weight all of which can affect
the developing lungs (Sacks et al. 2011). For these
reasons, it is important to try to limit children's
vigorous outdoor activities during wildfire events.
Although the focus of this document is wildfire
7
-------
smoke, children may encounter other environmental
hazards including air pollutants from burning
structures and furnishings, and exposure to fire ash if
children are present during fire clean up.
Wildfire smoke can persist for days or even months,
depending on the extent of the wildfire. Symptoms
of wildfire smoke inhalation, which can include
coughing, wheezing, difficulty breathing, and
chest tightness, are supported by evidence from
epidemiologic studies of particulate matter that
report increased respiratory symptoms and decreased
lung function (U.S. EPA, 2009). Air pollution
from wildfires can exacerbate asthma symptoms
and trigger attacks. Research has shown a higher
rate of asthma emergency department visits and
hospital admissions for children, especially infants
and very young children, during and after wildfires
(Hutchinson et al., 2007). Even children without
asthma could experience respiratory symptoms,
resulting in school absences and other limitations of
normal childhood activities.
In addition to the overt health effects and underlying
physiologic differences between children and adults,
children may also experience significant emotional
distress, resulting from anxiety and grief following
a wildfire. It is important to consider not only the
potential physical health implications of wildfire
smoke on children, but also the potential longer-term
psychological implications.
See factsheet Protecting Children from Wildfire
Smoke and Ash.
Pregnant women. During pregnancy, physiologic
changes, such as higher respiratory rates and
increases in blood and plasma volumes, increase a
woman's vulnerability to environmental exposures.
Additionally, during critical windows of human
development, a mother's exposure to wildfire smoke
may harm the developing fetus. A few studies have
examined potential health effects of wildfire smoke
exposure during pregnancy. Holstius et al. (2012)
examined the effect of wildfire smoke on pregnancy
outcomes in Southern California and reported some
evidence indicating a potential reduction in birth
weight due to in utero exposure to wildfire smoke. In
addition, psychosocial stress exacerbated by wildfires
is another mechanism through which wildfire events
may affect the health of pregnant women and their
fetuses (Kumagai et al. 2004). While there are few
studies examining the health effects of exposure
to wildfire smoke on pregnancy outcomes, there
is some available evidence of health effects due to
exposures to other combustion-related air pollutants.
Specifically, there is substantial evidence of low birth
weight due to repeated exposures to cigarette smoke,
including both active and passive smoking and an
emerging, but still inconsistent body of literature on
the health effects of prenatal exposure to ambient
air pollution. Specifically, studies examining chronic
maternal exposure to ambient particulate matter (U.S.
EPA 2009) and indoor biomass smoke (e.g., Amegah
et al. 2014) from wood-fired home heating devices
have provided some evidence of adverse birth and
obstetrical outcomes (e.g., decreased infant birth
weight, preterm birth).
Older adults. The number of U.S. adults 65 years
of age and older will nearly double between 2012
and 2050 (Ortman et al. 2014). Older adults are
at increased risk of health effects from short-
term exposures to wildfire smoke because of
their higher prevalence of pre-existing lung and
heart diseases, and because important physiologic
processes, including defense mechanisms, decline
with age. Epidemiologic studies of short-term
exposures to fine particles have reported greater
risks of emergency department visits and hospital
admissions and mortality, in older adults (U.S. EPA,
2009). Additional evidence from animal toxicological
studies and human clinical studies provides biological
plausibility and further support that older adults
should limit exposures to fine particle pollution, such
as wildfire smoke.
8
-------
Low socioeconomic status (SES). SES is often
defined in epidemiologic studies using a variety of
indicators such as educational attainment, median
household income, percentage of the population in
poverty, race/ethnicity, and location of residence. It
is well-recognized that SES is a composite measure
that encompasses multiple individual indicators
along with other factors and is often measured at
the population- or community-level. Epidemiologic
studies of fine particulate matter using indicators
of SES provide initial evidence that individuals of
low SES may be at increased risk of mortality due
to short-term exposures. With respect to wildfire
smoke the evidence is much more limited, although
Rappold et al. (2012) and Reid et al. (2016) reported
some evidence that locations classified as having the
lowest SES were at the greatest risk of health effects
attributed to wildfire smoke.
In addition, SES may contribute to differential
exposures to wildfire smoke across communities.
For example, access to air conditioning reduces
infiltration of particle pollution indoors. Less access
to air conditioning may lead to greater exposure to
wildfire smoke and greater sensitivity to extreme
heat and, subsequently, health disparities across
communities. People of color and impoverished
children and adults bear a disproportionate burden
of asthma and other respiratory diseases and
therefore they may be at increased risk of health
effects due to wildfire smoke exposure (Brim et al.
2008, CDC 2014). As a result, additional outreach
activities and support may be required to properly
communicate the actions that people of low SES
should take to both reduce and protect themselves
from wildfire smoke exposures.
Outdoor workers. Working outdoors during periods
of wildfire smoke exposure could result in a range
of health effects depending on the underlying health
status of the worker. Effects of exposure to wildfire
smoke range from eye and respiratory tract irritation
to the triggering of an asthma exacerbation or
cardiovascular event. For workers that encompass a
previously identified at-risk population or lifestage,
and workers who are negatively impacted by smoke
exposure, some of the same recommendations
listed in this document for the general public apply
when working outdoors in a smoky environment.
See C 'haptier 5 (Protecting Outdoor Workers) for
more information.
Summary
Particulate matter is the principal public health
threat from exposure to wildfire smoke. The
effects of particulate matter exposure range from
eye and respiratory tract irritation to more serious
disorders including reduced lung function, bronchitis,
exacerbation of asthma and heart failure, and even
premature death. Although exposure to fine particles
can lead to a range of health effects, certain lifestages
and populations are at greatest risk of health effects
due to fine particle exposures (Table 1). While
evidence about the implications of repeated or
prolonged smoke exposures on health is very limited,
when smoke exposure is expected to be prolonged,
public health officials should consider all options in
communicating the importance of actions that can
be taken to reduce smoke exposure.
9
-------
Table I. Summary of lifestages and populations potentially at-risk of health effects from
wildfire smoke exposures.
At-risk
Lifestage/
Population
Rationale and Potential Health Effects from Wildfire Smoke Exposure
People with asthma
and other respiratory
diseases
Rationale: Underlying respiratory diseases result in compromised health status that can result in the triggering of
severe respiratory responses by environmental irritants, such as wildfire smoke.
Potential health effects: Breathing difficulties (e.g.. coughing, wheezing, and chest tightness) and exacerbations of
chronic lung diseases (e.g., asthma and COPD) leading to increased medication usage, emergency department visits,
and hospital admissions.
People with
cardiovascular disease
Rationale: Underlying circulatory diseases result in compromised health status that can result in the triggering of
severe cardiovascular events by environmental irritants, such as wildfire smoke.
Potential health effects: Triggering of ischemic events, such as angina pectoris, heart attacks, and stroke: worsening of
heart failure; or abnormal heart rhythms could lead to emergency department visits, hospital admissions, and even
death.
Children
Rationale: Children's lungs are still developing and there is a greater likelihood of increased exposure to wildfire
smoke resulting from more time spent outdoors, engagement in more vigorous activity, and inhalation of more air
per pound of body weight compared to adults.
Potential health effects: Coughing, wheezing, difficulty breathing, chest tightness, decreased lung function in all
children. In children with asthma, worsening of asthma symptoms or heightened risk of asthma attacks may occur.
Pregnant women
Rationale: Pregnancy-related physiologic changes (e.g.. increased breathing rates) may increase vulnerability to
environmental exposures, such as wildfire smoke. In addition, during critical development periods, the fetus may
experience increased vulnerability to these exposures.
Potential health effects: Limited evidence shows air pollution-related effects on pregnant women and the developing
fetus, including low birth weight and preterm birth.
Older adults
Rationale: Higher prevalence of pre-existing lung and heart disease and decline of physiologic process, such as
defense mechanisms.
Potential health effects: Exacerbation of heart and lung diseases leading to emergency department visits, hospital
admissions, and even death.
People of low
socioeconomic status
Rationale: Less access to health care could lead to higher likelihood of untreated or insufficient treatment
of underlying health conditions (e.g., asthma, diabetes). Less access to measures to reduce exposure (e.g., air
conditioning) could lead to higher levels of exposure to wildfire smoke.
Potential health effects: Greater exposure to wildfire smoke due to less access to measures to reduce exposure,
along with higher likelihood of untreated or insufficiently treated health conditions could lead to increased risks of
experiencing the health effects described above.
Outdoor workers
Rationale: Extended periods of time exposed to high concentrations of wildfire smoke.
Potential health effects: Greater exposure to wildfire smoke can lead to increased risks of experiencing the range of
health effects described above.
10
-------
II. WILDFIRE SMOKE AND
AIR QUALITY IMPACTS
^to-
il
-------
Composition of wildfire smoke
Smoke from combustion of natural biomass is
a complex mixture of particulate matter, carbon
dioxide, water vapor, carbon monoxide, hydrocarbons
and other organic chemicals, nitrogen oxides, and
trace minerals. The individual compounds present
in smoke number in the thousands. Most research
on wildland fire emissions has centered on natural
biomass fuelsdie vegetative materials comprised
of trees, needles, leaves, branches, litter, duff, stumps,
grasses, shrubs, and downed trees. Wildfires may also
move into the WUI burning homes and structures in
the process and thus consuming man made materials
in addition to natural fuels. More research is needed
to understand potential health impacts of breathing
this complex mix of natural and man made material
emissions.
The Clean Air Act requires EPA to set National
Ambient Air Quality Standards (NAAQS) for
pollutants considered harmful to public health
and the environment.: EPA has set NAAQS for six;
principal pollutants, including three pollutants that
may be of concern during wildfire smoke events:
particulate matter (regulated in two size categories:
PM and PM, j, ground level ozone (03), and
carbon monoxide (CO).
In wildfire smoke, particulate matter, especially the
smallest size component PM 5, is the principal air
pollutant of concern for public health. Particulate
matter is a generic term for particles suspended in
the air, typically as a mixture of both solid particles
and liquid droplets. The size of the particles (Figure
1) affects their potential to cause health effects.
Particles larger than 10 micrometers in diameter do
not usually reach the lungs though they can irritate
the eyes, nose, and throat. Particles with diameters
less than 10 micrometers (PM,0) can be inhaled
into the lungs and affect the lungs, heart, and blood
vessels. The smallest particles, those less than 2.5
micrometers in diameter (PM ^ are the greatest risk
to public health because they can reach deep into the
lungs and may even make it into the bloodstream.
Most of the effort to quantify, describe, and monitor
smoke and health effects from wildfires focuses on
Figure I. Fine, inhalable particulate matter (PM} j is the
air pollutant of greatest concern to public health from
wildfire smoke because it can travel deep into the lungs
and may even enter the bloodstream.
PM, . Particles from smoke tend to be very small,
with a size range near the wavelength of visible
light (0.40.7 micrometers), and therefore efficiently
scatter light and impact visibility, which can pose
a serious safety risk when smoke crosses roads or
impacts airports.
Two other pollutants that may be of concern during
wildfire smoke events are carbon monoxide and
ozone. Carbon monoxide is a colorless, odorless
gas produced by incomplete combustion of wood
or other organic materials. Carbon monoxide dilutes
rapidly so is rarely a concern for the general public,
or people with heart disease who are at-greater
risk from exposure, unless they are in very close
proximity to the w'ildfire (generally within three
miles of the fire line and when smoldering fuels
are present). Carbon monoxide can be a concern
to firefighters close to the fire line. Smoke episodes
can also be associated with elevated levels of ozone.
Ozone is not emitted directly from a wildfire but
forms in the plume as smoke moves downwind. It
can be further enhanced if given the opportunity to
mix with urban sources of nitrous oxides. Note that
ozone is not always enhanced downwind of a fire as
the formation and breakdown of ozone is a complex
photo-chemical process.
(microns) in diameter
HUMAN HAIR
90 (Xm (microns) in diameter
FINE BEACH SAND
C PM2.5
Combustion particles, organic
compounds, metals, etc.
< 2.5 |im (microns) in diameter
4* PM10
Dust, pollen, mold, etc.
:10 |im (microns) in diameter
12
-------
7~H,rT:"nr*-T-
Vegetation
/ / S7
i
'"J;
--L
>
y>
tB,r
"T"1-
J J
0
! J
MID-LATITUDE
FOREST
| Coniferous Forest
| Broadleaf Forest
f Mixed Coniferous
and
Broadleaf Forest
] Woodland and
Shrub
(Mediterranean)
MID LATITUDE GRASSLAND
I I Short Grass (Steppe)
, 1 [ Tall Grass (Prairie) IH SWAMP
iig TROPICAL ~ DESERT AND I
RAINFOREST DESERT SHRUB
1 TROPICAL rI pcpuAurur ipr ~ UNCLASSIFIED
GRASSLAND 14 PERMANENT ICE
|TUNDRA AND
ALPINE
Figure 2. Wildfire rate of spread, fuel consumed, smoke produced, and duration are all influenced by vegetation
type. Fires in grass fuels tend to spread quickly and burn out quickly. Fires in brush fuel types can burn hot
and spread fast if weather conditions are right. Fires in forest fuel types can range from slov,v moving to rapidly
spreading; long lasting fires in this fuel type tend to produce the most serious and prolonged smoke impacts but
smoke can cause problems from wildfires in all fuel types.
Many other chemicals are present in wildfire smoke
but at much lower concentrations than particulate
matter, ozone, and carbon monoxide. These include
an extensive list of HAPs that can be potent
respiratory irritants and carcinogens. Given that
the specific effects of these pollutants are hard
to quantify and measure during an active smoke
incident, PM, g is typically the pollutant that is tracked
and monitored, and the pollutant that is used to
estimate public health effects from wildfire smoke
Characteristics of wildfires
Wildfires need three conditions to startfuel,
oxygen and a heat sourcethese three together are
known as the fire triangle. Fuel is anything that can
burn such as grass, brush, trees and even homes and
other structures. The more fuel there is to burn, the
more intense a fire can be. Fire needs oxygen to grow
and winds increase oxygen supply and fire intensity.
Plus, winds can push heat from the fire into new
areas, preheating and drying fuels and moving the fire
rapidly forward. Heat sources spark the fire and bring
fuel temperatures hot enough to ignite and burn. The
sun, lightning, burning campfires, cigarettes, sparks,
and hot winds are all examples of heat sources
13
-------
1
m
Figure 3. Strong winds can cause rapid fire spread and move smoke into communities far from a wildfire. In 2018,
smoke from the Camp fire caused weeks of poor air quality in the San Francisco Bay area (a). Light winds and
stable atmospheric conditions cause smoke to pool near a wildfire and flow down valleys to nearby communities as
seen in central Idaho in 2012 (b).
necessary to start and promote growth of wildfires.
Once ignited, fuels, weather, and topography govern
fire behavior and determine how fast the fire spreads,
how intensely it burns, and how much smoke it will
put into the air on a given day. The changing climate
is also influencing the frequency, duration, and
severity of wildfires due to a warming climate, longer
fire seasons, and increases in drought conditions
(Westerling et al. 2003; USGCRP 2018).
Wildland fuels
The general characteristics of wildland fuels help
predict some of what will happen during a wildfire
smoke incident. Very generally, natural fuel fires can
be described in three large and diverse categories:
grass, brush, and forest (Figure 2). Wildfires in
grass typically spread very rapidly but generally
burn themselves out and are brought under control
within hours to days of ignition. Brush-type fuels,
for example chaparral, gallberry, and ceanothus
often contain volatile compounds that result in hot,
fast moving fires that are very difficult to control
especially if the brush is growing on slopes or in
dense clusters. Wildfires in forest fuel types can range
from mild to severe in intensity and can spread very
slowly or extremely rapidly depending on weather
and tuel conditions. Fires in forests can last for
weeks or months and are often the wildfire type that
results in the most severe and longest duration air
quality impacts. Fires in forest fuel types are more
likely to be in remote and inaccessible areas making
firefighting more difficult. Wildfires of course often
burn over multiple fuel types and may start in one
fuel type before moving into another.
The amount and type of fuel and its moisture
content affect smoke production, as does the stage
of combustion (flaming and smoldering). The
smoldering phase of a fire when large rotten logs
and duff or peat are consumed, can sometimes
result in high particle emissions due to less
complete combustion than when flames are present.
Smoldering fuels are the sign of a cooler fire so
smoke generally stays closer to the source and closer
14
-------
to the ground, and air quality impacts are often closer
to the fire, especially at night and downslope of
smoldering activity.
Meteorology arid smoke
Weather conditions such as wind, temperature, and
humidity contribute to fire behavior and smoke
accumulation. Winds brings a fresh supply of oxygen
to the fire and pushes the fire into new fuels. Strong,
hot, and dry winds can cause a wildfire to grow
very rapidly or "blow up". Winds also move smoke
away from the fire and contribute to atmospheric
mixing meaning smoke impacts to the public may
be lessened near the fire although winds can move
smoke long distances into communities far from
where the wildfire is burning (Figure 3).
Once smoke enters the atmosphere, its concentration
at any one place and time depends on mechanisms
of transport and dispersion. Transport refers to
whatever process may carry a plume vertically or
horizontally in the atmosphere. Vertical transport is
controlled by the buoyancy of the smoke plume and
stability of the atmosphere. Horizontal transport
is controlled by wind. The larger the volume of
space that smoke is allowed to enter and the farther
it can be transported, the more dispersed and less
concentrated it will become.
The intense heat generated by an active wildfire
drives smoke high into the air where it remains until
it cools and begins to descend. As smoke moves
downwind, it becomes more dilute and often more
widespread, eventually reaching ground level. Terrain
also affects localized weather. For example, as the
sun warms mountain slopes, air is heated and rises,
bringing smoke and fire with it. After sunlight passes,
the terrain cools and the air begins to descend. This
creates a down-slope airflow that can alter the smoke
dispersal pattern seen during the day. These daily
cycles sometimes help predict repeating patterns of
smoke impacts in communities.
In the evening, especially in mountain valleys and
low-lying areas, temperature inversions in which the
air near the ground is cooler than the air above are
common. Temperature inversions prevent upward
air movement. The lid effect of inversions, coupled
with a drop in wind speed, can favor smoke and
pollutant accumulation in valleys close to the fire at
night. Strong inversions can also allow for smoke
to accumulate in an area for days or weeks with
little opportunity for clean air to help improve
smoke concentrations.
Smoke levels in populated areas can be difficult to
predict and will often depend on a suite of local
terrain, weather, and fire-behavior-based factors. A
wind that usually clears out a valley may simply blow
more smoke in or may fan the fires, causing a worse
episode the next day. Smoke concentrations change
constantly. Sometimes, by the time officials can issue
a warning or smoke advisory, the smoke may already
have cleared.
Wildland fire management
Most of the tens of thousands of wildfires in the
United States are suppressed during initial attack
efforts. For many jurisdictions, from federal to
private lands, there are specific plans in place
addressing fire suppression efforts and response. For
federal land managers, land management plans are
created with annually updated fire management plans
that help guide the appropriate response to a wildfire
in a specific area. When these land management
plans are revised, they undergo public review, which
provides an opportunity for input on how the land is
managed by a federal agency.
When there is an ignition, whether human caused or
from lightning, the first order of business is always
protecting the safety of the public and fire fighters.
Some wildfires continue past the initial attack or
occur in areas where the risks of attack are high or
the likelihood of suppression success is low. Such
fires can become large, of long duration, and a
significant source of smoke. When these wildfires
elude initial attack efforts, exceed local firefighting
capabilities, or become large quickly, the land owner
or, for federal lands, the agency administrator, has
15
-------
the opportunity to engage external assistance for
additional resources to assist their local efforts. On
these types of fires, an Incident Management Team
(IMT) is usually engaged. The land owner/manager/
agency administrator where the wildfire is burning
advises the IMT on strategies, constraints, and
priorities so that fire management and suppression
efforts align with other land management goals
in the area.
Fire management strategies designed for a remote
wildfire in a wilderness area will be much different
from tactics used on lands adjacent to or in
communities. Wildfires in remote areas with no risk
to public resources may be monitored and largely
left to take a natural course and eventually burn
themselves out, especially when firefighting resources
are scarce. Similarly, only sections of a wildfire
may be suppressed due to resource capabilities or
threats to public and private resources. Wildfires
that threaten homes or other infrastructure will be
attacked aggressively. This may include retardant
drops from aircraft, bulldozers, fire engines, and
multiple 20-person fire crews. Public and firefighter
safety is considered above all else in determining the
fire management or suppression approach that will
be implemented.
Incident Management Teams
An IMT is a group of trained professionals that
respond to national, regional, or local emergencies.
IMTs are used to manage large-scale, complex
wildfire incidents. Team members have expertise in
finance, logistics, operations, information, safety,
planning, public information, and other areas needed
to manage a wildfire. Every incident management
team has an incident commander to oversee and
control the infrastructure of the team. IMTs work,
eat, and sleep in a safe location near the wildfire
frequently in camps or nearby public facilities. The
IMTs hold both public and cooperator meetings
where updates about the fire, upcoming fire tactics,
and concerns are discussed. These are important
opportunities for engagement on smoke issues.
If smoke and air quality issues become a concern,
the IMT can order a technical specialist called an Air
Resource Advisor (ARA). ARAs come from a variety
of backgrounds but have specialized training in
health effects of fine particles, air quality monitoring,
smoke dispersion modeling, predicting future air
quality, and communicating this information to the
public in an understandable and consistent way.
Much of the work of an ARA fits well with the work
of public health officials because ARAs produce a
"Smoke Outlook" that tells when and where smoke
levels will be high during the next couple of days.
Further discussion and an example outlook can be
found in Cha.oter 4.
16
-------
III. SPECIFIC STRATEGIES TO
REDUCE EXPOSURE TO
WILDFIRE SMOKE
17
-------
In areas where the public is experiencing wildfire
smoke exposure, public health and air quality
agencies should provide advice on actions that can
be taken to reduce smoke exposure. The following
strategies to reduce wildfire smoke exposure can be
used individually or in combination by individuals
and communities, as feasible and appropriate
for the smoke event they are experiencing.
Recommendations for communicating these
strategies to the public are provided in Chapter S and
summarized in '.Fable 4.
Individuals with heart or lung disease who are
concerned about the potential health implications of
exposure to wildfire smoke and actions they can take
to limit exposures, should be advised to discuss this
with their primary health care provider. They should
also check the Air Quality Index (AQI, discussed
below) each day for the air quality forecast and for
information about ways to reduce exposure.
Stay indoors
The most common advisory issued during a smoke
episode is to stay indoors. The effectiveness of this
strategy depends on how well the building limits
smoke from coming indoors, and on efforts to
minimize indoor pollution sources. Staying indoors
will provide some protection from smoke, especially
in a tightly closed, air-conditioned home in which
the air conditioner recirculates indoor air. Generally,
newer homes are "tighter" and keep ambient air
pollution out more effectively than older homes.
Staying inside with the doors and windows closed
can reduce the entry of outdoor air into homes, in
some cases by a third or more (Howard-Reed et al.,
2002). Homes with central air conditioning generally
recirculate indoor air, though some smoky outdoor
air can still be drawn inside (e.g., when people enter
or exit or when the central system can be set to bring
in outdoor air). In homes without air conditioning,
indoor concentrations of fine particles can approach
70100% of the outdoor concentrations; however, it
is more common that the indoor concentrations of
fine particles that come from outdoors are 50% or
less of outdoor concentrations when windows and
doors are closed (Allen et al. 2012, Chen and Zhao
2011, Singer et al. 2016). In very leaky homes and
buildings, outdoor particles can easily infiltrate the
indoor air, so guidance to stay inside may offer little
protection. In any home, if doors and windows are
open, particle levels indoors and outdoors will be
about the same.
Sometimes smoke events can last for weeks or even
months. These longer events are usually punctuated
by periods of relatively clean air. When air quality
improves, even temporarily, residents should "air
out" their homes to reduce indoor air pollution.
People who wish to clean their residences after or
between wildfire smoke events should use cleaning
practices that reduce re-suspension of particles that
have settled, including damp mopping or dusting and
using a high-efficiency particulate air (HEPA) filter-
equipped vacuum.
Staying indoors is a recommended strategy for
avoiding both heat and smoke exposure, as long as
the indoor air environment is protected. In high-
heat conditions, people are advised to stay cool, stay
hydrated, and stay inside. An important caveat about
advising people to stay inside and close windows
and doors of homes without air conditioning is the
increased risk of heat stress. Even without smoke
exposure, extreme heat poses a substantial health
risk, especially for at-risk groups, including young
children, the elderly, those with chronic diseases
or disabilities, and pregnant women. These at-risk
groups largely overlap with those at higher risk from
smoke exposures. Heat-related illnesses include heat
exhaustion, heat stroke and death. Warning signs
include heavy sweating, muscle cramps, weakness,
headache, nausea, vomiting, paleness, confusion,
fainting (passing out), and dizziness. To prevent
overheating, use cool compresses, misting, showers,
baths, and drink plenty of water. In some high-
heat conditions, windows and doors will need to be
opened to allow cooling even if smoke enters.
People who do not have air conditioning at home
should be advised to visit family members, neighbors,
or public buildings with air conditioning and
appropriate air filtration (such as a shopping mall,
library, cooling center, or movie theatre) during high
18
-------
smoke conditions to cool off for a few hours each
day. Public health officials should get information
about cooling and filtration status of buildings before
recommending where people can seek shelter from
heat or smoke. Some public buildings may have older
heating, ventilating, and air-conditioning (HVAC)
systems that use low-efficiency filters (see section
below on air conditioners and filters).
In preparation for the fire season or a smoke event,
it is a good idea to have enough food on hand to last
several days, to minimize driving and trips outdoors.
Foods stored for use during the fire season should
not require frying or broiling, since these activities
can add particles to indoor air. It is also important to
have at least a several-day supply of medication for
the same reason.
Guidance on protecting office and other indoor
workers from wildfire smoke has been developed
by the California Division of Occupational Safety
and Health (Cal/OSHA), in consultation with
technical staff from several other California agencies
(Appendix D) . This guidance describes how to
maximize the protection provided by HYAC systems
common in public and commercial buildings, as well
as other steps to protect occupants.
Reduce activity
Reducing physical activity lowers the dose of inhaled
air pollutants and reduces health risks during a
smoke event. When exercising, people can increase
their air intake 10 to 20 times over their resting level.
Increased breathing rates bring more pollution deep
into the lungs. People tend to breathe through their
mouths during exercise, bypassing the natural filtering
ability of the nasal passages and delivering more
pollution to the lungs. They also tend to breathe
more deeply, modifying the usual patterns of lung
particle deposition. This guidance addresses outdoor
exercise during smoky periods; residents need not be
discouraged from indoor exercise in an environment
with acceptable air quality.
Reduce other sources of indoor
air pollution
Indoor sources of air pollution such as smoking
cigarettes, using gas or wood-burning stoves and
furnaces, spraying aerosol products, frying and
broiling meat, burning candles and incense, and
vacuuming can all increase indoor particle levels.
Some of these same pollutants are also present
in wildfire smoke. Reducing indoor air pollutant
emissions during smoke events can decrease indoor
particle levels.
Cigarette smoke significantly increases levels of
particles and other pollutants. For instance, in a
closed room of 125 square feet, it takes only 10
minutes for the smoke of four cigarettes to generate
hazardous levels of particles (644 micrograms per
cubic meter of air or /zg/m3 PM25) The second
largest source of indoor air pollutants is indoor
combustion sources without proper ventilation to the
outdoors. "Room-vented" or "vent-free" appliances
such as unvented gas or propane fireplaces,
decorative logs, and portable heaters can contribute
substantial quantities of particles to indoor air and
are of significant concern. Frying or broiling some
foods also can produce high levels of particles in
the kitchen and dining areas. These sources can
also increase the levels of polycyclic aromatic
hydrocarbons (PAHs), carbon monoxide, acrolein,
and nitrogen oxides, all of which are potentially
harmful to health. In addition, small sources such as
candles and incense burning can produce surprisingly
large quantities of particles and should not be used
during wildfire smoke events. To avoid re-suspending
particles, do not vacuum during a smoke event,
unless using a HEPA-filter-equipped vacuum. When
cleaning, use a damp mop or damp dust cloth to
minimize re-suspending settled particles.
Use air conditioners and filters
When wildfire risk rises, and before the smoke
arrives, public health agencies can help their
communities prepare by developing public service
announcements with information about upgrading
the filters in their central air systems. The message
should include information about different filter
19
-------
types, the importance of stocking up on filters ahead
of wildfire season, and how to turn off fresh air
intakes. Highlight the importance of creating clean
air spaces in homes with individuals in at-risk groups
and encourage residents to install high-efficiency
filters (MERV 13 or higher), if possible. Engage
with local health care professionals and provide
information they can pass on to their patients. A
fact sheet on indoor air filtration and air cleaners is
available at: https: / /www3.eoa.p~ov /airflow/smoke
fires/indoor-air-fiitratiori-factsheet-SOB.pdt-
Homes with central air conditioners generally have
lower concentrations of particles from the outdoors
compared to homes that use open windows for
ventilation. Much less is known about the effect
of using various types of room air conditioners
(e.g., window units) and their air filters on smoke
concentrations in homes. Most air conditioners
are designed by default to recirculate indoor air.
Those systems that have both "outdoor air" and
"recirculate" settings need to be set on "recirculate"
during smoke events. Other types of air conditioners,
such as swamp coolers, can actually bring in large
quantities of outdoor air. Below is a brief overview
of common types of cooling systems.
Central air systems
Central heating and air conditioning systems (and
some room air conditioners) contain filters that
remove some airborne particles with different
degrees of efficiency. The most helpful parameter for
understanding the efficiency of HVAC filters is the
fractional removal efficiency. The most widely used
test method for HVAC filters in the United States is
the American Society of Heating, Refrigerating and
Air-Conditioning Engineers (ASHRAE) Standard
52.2, which evaluates the removal efficiency for
particles 0.3 to 10 [j.m in diameter. Results are
reported as a Minimum Efficiency Reporting Value
(MERV) ranging from MERV 1 to MERV 16 based
on the average removal efficiency across three
particle size ranges: 0.31 [j.m, 13 [j.m, and 310 [j.m
(Table 2). Other commercially common proprietary
rating systems for in-duct air filters include the
Microparticle Performance Rating (MPR) and Filter
Performance Rating (FPR). In general, the higher the
filter rating, the higher the filter's removal efficiency
for at least one particle size range.
If possible, the HVAC filter should be replaced
with a pleated medium- or high-efficiency particle
filter. Higher-efficiency filters (e.g., filters rated
at MERV 13 or higher) are relatively inexpensive
and preferred because they can capture more of
the fine particles associated with smoke and can
reduce the amount of outdoor air pollution that
gets indoors. However, caution must be taken to
ensure that the central system is able to handle the
increased airflow resistance from a higher-efficiency
filter. Consultation with an HVAC technician or the
central air system manufacturer may be necessary
to confirm if or which high-efficiency filters will
work with an individual system. Filters need to
be replaced regularly and should fit the filter slot
snugly. Filters only remove particles while the
system fan is operating and passing air through the
filter. Regardless of whether a filter upgrade has
been performed, during a wildfire smoke event, the
central system's circulating fan can be set to operate
continuously (i.e., fan switch on the thermostat set
to "ON" rather than "AUTO") to obtain maximum
particle removal by the HVAC filter, although this
will increase energy use and costs (Fisk and Chan
2017). The thermostat can be reset back to "AUTO"
after the wildfire smoke clears.
In addition to high- and medium-efficiency filters,
electrostatic precipitators (ESPs) or other electronic
particle air cleaners can sometimes be added by a
technician to central air conditioning systems to
keep particle levels in indoor air within acceptable
levels during a prolonged smoke event. However,
ESPs may produce some amount of ozone
as a byproduct, so only ESPs that have been
independently tested and produce little or no ozone
should be used.
For newer air conditioners with a "fresh air
ventilation system" that brings in outdoor air
continuously or semi-continuously, the "fresh air"
setting for the system should be turned off during
smoke events. This may require closing the outdoor
20
-------
air damper or sealing off outdoor air intakes, setting
the system on "recirculate" only, or turning off the
energy- or heat-recovery ventilator or exhaust fans
that are part of the system. If the control system
instructions are not clear or accessible, residents
should contact their builder or heating and cooling
contractor to help temporarily adjust the system.
However, residents should also place a reminder tag
in a visible spot so that they reset the system once the
smoke clears.
Many newer homes currently have whole-dwelling
mechanical ventilation systems that intentionally
bring outdoor air inside, often designed to meet
the requirements of ASHRAE Standard 62.2. This
can be achieved through dedicated supply ductwork
(creating positive pressure in the building), controlled
exhaust ventilation (creating negative pressure in the
building), or "balanced" ventilation strategies that
typically employ a heat recovery or energy recovery
ventilator (HRV/ERV). Mechanical ventilation
in new homes is now required by building codes
in some jurisdictions. These systems may need to
be turned off or adjusted during periods of high
outdoor air pollution from wildfires to avoid entry of
outdoor air pollutants, especially exhaust ventilation
systems. Mechanical ventilation systems used in
public and commercial buildings differ and are
discussed further in appendices B and D.
Swamp coolers
Many older homes use evaporative coolers, known as
"swamp coolers," to condition the air in the home. A
cooler unit operates by evaporating water off large
pads located in the cooler housing. The unit also
contains the fan motor, fan, water tray, and pump
and is usually located on the roof of a house. The
coolers rely on bringing large volumes of outside air
into the home and they will not cool effectively if
the home is sealed up and the incoming air cannot
be exhausted from the home. Although a laboratory
study has shown that evaporative coolers can reduce
PM10 up to 50%, and PM05 by 1040% (Paschold et
al., 2003), other outdoor pollutants such as ozone are
not filtered out and can reach indoor levels that are
nearly equal to the outdoor levels. Therefore, unless
there is a heat emergency, evaporative coolers should
not be used during periods when there is heavy
smoke outside.
Ductless mini-split systems
Some new or recently renovated homes may have
ductless mini-split heat pumps or air conditioning
systems. Ductless mini-split systems, which use an
air handling unit mounted inside the home's pressure
boundary, will still cool effectively in a home that
has been sealed up to minimize smoke infiltration
and generally do not compromise indoor air quality.
These systems have the advantage of not requiring
Table 2. Particle size efficiency for select MERV ratings*
MERV Rating
Average Particle Size Removal Efficiency (%)
Particle Size (|jm)
0.3-1.0
1.0-3.0
3.0-10.0
Low (1 4)
n/a
n/a
<20
Medium (5-8)
n/a
>20+
20 to >70
Medium (9-12)
20 to >35++
35 to >80
75 to >90
High (13-16)
50 to >95
>85
>90
HEPA( 17-20)**
>99.97
^Adapted from ANSI/ASHRAE Standard 52.2
**Not part of the official ASHRAE Standard 52.2 test but added for comparison purposes
n/a: Not applicable to MERV rating (not tested)
+ Not applicable for MERV 5-7
++Not applicable for MERV 9-10
21
-------
ductwork throughout the attic or basement space.
From an air-balance standpoint, these systems do
not significantly affect the air pressure in the home
and do not result in extra air being brought into or
exhausted from the home. Some mini-split systems
include ducts connected to a low-profile air handler,
which may be installed in an unconditioned area and
may be susceptible to outdoor air exchange issues,
depending on the effectiveness of the duct sealing
during installation.
Window-mounted and portable air
conditioners
Some residences are cooled or heated using window-
mounted air conditioners. To function properly
and efficiently, these units must form a tight seal
with the window frame in which they are mounted.
People who have window units should be advised to
check the quality of the seal by looking around the
perimeter of the window unit for any visible gaps.
Light or air leaking in from the outside is an easy way
to determine whether the seal is tight. Also, window
units can be operated in recirculation mode or fresh
air mode. During a high smoke event, people should
be advised to set the window AC unit to operate in
recirculation mode.
Use of a single-hose portable air conditioner might
result in outdoor smoke being drawn into the
home. Portable air conditioners are usually used to
condition the air in a single room of the home. These
units have a cooling capacity that can range from
6,000 to 15,000 BTU and many of these units also
have a heating mode of operation. Depending on
the make and model, a portable air conditioner will
have either a single- or dual-hose configuration. The
single-hose configuration expels hot exhaust air to
the exterior of the home, but the supply air is taken
from the home itself, so the net effect is that the
room is placed under slight negative pressure. This
means that air is drawn into the home through any
leaky points in the building envelope. This is not a
problem with dual-hose configurations, because they
draw and deliver supply air from the outside so the
air pressure inside the room remains balanced.
Use room air cleaners
Choosing to buy an air cleaner is a decision that
ideally should be made before a smoke emergency
occurs, particularly in homes with occupants in at-
risk groups. During a smoke emergency, it may be
hazardous to go outside or drive, and appropriate
devices may be in short supply. It is unlikely that local
health officials or non-governmental organizations
will be able to buy or supply air cleaners to those
who might need them. Note that air cleaners are
frequently referred to as "air purifiers" by retailers
and the general public.
Choose an air cleaner appropriate for the size
of the indoor environment
Air cleaners can help reduce indoor particle levels,
provided the specific air cleaner is properly matched
to the size of the indoor environment. Room air
cleaners are available as portable units designed to
clean the air in a single room ($90$900). Central air
cleaners, which may be large portable units or in-duct
units installed by an HYAC professional, are intended
to clean the whole house ($450$1,500). Central
air cleaners can be more effective than room air
cleaners (depending on how much they are operated),
although two or more well-placed portable air
cleaners can be equally effective, and their cost may
still be less than a large central air cleaner.
Room air cleaner units should be sized to provide a
filtered airflow at least two to three times the room
volume per hour. Most portable units will state on
the package the unit's airflow rate, the room size it
is suitable for, its particle removal efficiency, and
perhaps its Clean Air Delivery Rate (CADR). The
CADR is a rating that combines efficiency and
airflow.
The Association of Home Appliance Manufacturers
(AHAM) maintains a certification program for air
cleaners. The AHAM seal on the air cleaner's box lists
separate CADR numbers for tobacco smoke, pollen,
and dust. Higher numbers indicate faster filtration
of the air. For wildfire smoke, choose a unit with a
tobacco smoke CADR at least 2/3 of the room's
area. For example, a 10' x 12' room (120 square feet)
would require an air cleaner with a tobacco smoke
22
-------
CADR of at least 80. If the ceiling is higher than 8',
an air cleaner rated for a larger room will be needed.
Choose an air cleaner that effectively removes
particles without producing ozone
The two common mechanisms for particle removal
include:
Mechanical air cleaners that contain a. fiber or
fabric filter. The filters need to fit tightly in their
holders and be cleaned or replaced regularly.
HEPA filters (and Ultra-Low Penetration Air
[ULPA] filters, which are not generally available
for residential use) are most efficient at removing
particles.
Electronic air cleaners, such as electrostatic pre-
cipitators (ESPs) and ionizers. ESPs use a small
electrical charge to collect particles from air
pulled through the device. Electronic air cleaners
usually produce small amounts of ozone (a respi-
ratory irritant) and some, especially those that are
combined with other technologies, may produce
substantial levels of ozone (see next section on
Ozone Generators). Only ESPs that have been
independently tested and documented to produce
little or no ozone should be used. Ionizers, or
negative ion generators, cause particles to stick to
materials (such as carpet and walls) near the de-
vice and are also often a source of ozone. Ionized
particles deposited on room surfaces can cause
soiling and, if disturbed, can be resuspended into
the indoor air.
Only portable (room) air cleaners that do not
produce ozone above 0.050 ppm should be used
(see below). The California Air Resources Board
(CARB) certifies air cleaners that produce little or no
ozone and only CARB-certified air cleaners may be
sold in California.
A list of CARB-certified air cleaners can be found
at: https: / /www.arb.ca.p-ov/research/indoor/
ai re lea, tie rs/certified.htm.
Place and operate the air cleaner to maximize
particle removal
Room air cleaners will provide the most protection
when placed where people spend the most time, such
as a bedroom. A good portable air cleaner placed in
a bedroom may be particularly helpful to a person
with asthma or COPD. For retired or homebound
individuals, the portable room air cleaner should
be set up in whichever room is used the most.
To maximize air cleaner effectiveness, operate it
continuously, or as often as possible. Use the highest
fan speed and make sure the air flow to the air
cleaner is not obstructed. Keep outside doors and
windows closed to prevent additional particles from
entering the room.
Air cleaners can be used in combination with central
air system filter upgrades described in the preceding
section to maximize the reduction of indoor
particles. Air cleaners alone can effectively reduce
particle concentrations even in homes that do not
have central air conditioning if windows and doors
remain closed and excessive heat is not a concern.
Under normal (non-smoky) conditions, portable
air cleaners fitted high-efficiency filters can reduce
indoor particle concentrations by as much as 90
percent (Singer et al. 2016). During a wildfire smoke
event, portable air cleaners fitted with high-efficiency
filters may reduce indoor particle concentrations by
as much as 45% (Fisk and Chan 2017).
Air cleaners for gases and odors
Most air cleaners are not effective at removing gases
and odors, although some specialized models that
perform this task well are available. Devices that
remove gases and odors can cost more than particle
air filters, both to purchase and maintain. They force
air through materials such as activated charcoal
or alumina coated with potassium permanganate.
However, with smaller-sized air cleaners, the filtering
medium can become quickly overloaded and may
need to be replaced often. Large gas-removing
devices may be useful for individuals that encompass
an at-risk lifestage or population and may require
less-frequent replacement of the filtering medium.
New models that combine particle and gas removal
are available in both portable and in-duct models.
Do-it-yourself box fan air cleaners
Some organizations provide instructions to assemble
a do-it-yourself (DIY) box fan air cleaner by
23
-------
attaching a high-efficiency filter to a box fan. There
is currently some limited evidence to support the
filtration efficacy of these DIY devices. However,
concerns have been raised that the box fan motor
may overheat when operated with a filter attached.
We expect there will be more research conducted
on the safety and efficacy of DIY air cleaners in
the coming years. In the meantime, though there is
not enough evidence for us to endorse their use, we
acknowledge that during a wildfire smoke event some
people may choose to assemble a DIY air cleaner
to reduce their exposure to wildfire smoke. Those
who make this choice should be advised to use the
device with caution and not to operate it unattended
or when sleeping, to avoid any potential fire or
electrical hazard.
For more information about residential air cleaners:
hftps: / / www.epa.gov / indoor-air-quaiity-iaq /air-
cleaners-and-air-filters-home
https:/ /www.a.rh.ca..gov/ research/indoor/
aircleaners / cotisumers.htm
http://ahanwerifide.org
Avoid ozone generators
Some devices, known as ozone generators, personal
air purifiers, "super-oxygen" air purifiers, and
"pure air" generators, are sold as air cleaners, but
the position of public health agencies, including
the California Air Resources Board and U.S.
Environmental Protection Agency, is that they do
more harm than good. These devices are designed
to intentionally produce large amounts of ozone gas.
Ozone generator manufacturers claim that ozone
can remove mold and bacteria from the air, but this
occurs only when ozone is released at levels many
times higher than those that are known to harm
human health.
Relatively low levels of ozone can irritate the
airways, causing coughing, chest pain and tightness,
and shortness of breath. Low levels of ozone can
also worsen chronic respiratory diseases such as
asthma and compromise the body's ability to fight
respiratory infections. As a result, using an ozone
generator during a smoke event may actually increase
the adverse effects from the smoke. In addition,
ozone gas does not remove particles from the air
and can lead to particle formation; ozone reacts
with certain chemicals commonly found indoors to
produce particles and formaldehyde. California now
prohibits the sale of air cleaners that emit potentially
harmful amounts of ozone. A list of air cleaners that
California has certified to emit little or no ozone is
available at:
https:/ /www.arb.ca.gov/ research/indoor/
atrcleaners / certified.htm
For more information about ozone generators
marketed as air cleaners:
https: / / www.epa.gOY / indoor-a.ir-auality-ia.a / ozotie-
generators-are-soid-air-cieariers
https:/ /www.arb.ca.gov/research/indoor/ozone.htm
Humidifiers
Humidifiers are not air cleaners and will not
significantly reduce the number of particles in the
air during a smoke event. Nor will they remove gases
like carbon monoxide. However, humidifiers and
dehumidifiers (depending on the environment) may
slightly reduce pollutants through condensation,
absorption, and other mechanisms. In an arid
environment, one possible benefit of running
a humidifier during a smoke event might be to
help the mucous membranes remain comfortably
moist, which may reduce eye and airway irritation.
However, if not properly cleaned and maintained,
some humidifiers can circulate mold spores and
other biological contaminants. The usefulness
of humidification during a smoke event has not
been studied.
24
-------
Create a clean room at home
Creating an in-home "clean room" is a good
exposure reduction strategy for people who live in
areas regularly affected by wildfire smokeespecially
those with pre-existing conditions that increase the
risk of air pollution-related health effects. It is also
a good strategy for those who must work outside
so that they can breathe cleaner air while indoors at
home after work. A good choice for a clean room
is an interior room with few windows and doors,
such as a bedroom. Anyone who cannot create an
adequate clean room in their own home should be
encouraged to seek out cleaner air shelters or cleaner
air spaces located in their communities for periods of
respite from the smoke (see discussion below).
Some suggestions for creating and maintaining a
clean room:
Keep windows and doors closed.
Set up a properly sized room air cleaner (see
above) to help remove particles from the air while
emitting little or no ozone.
Run an air conditioner or central air conditioning
system. If the air conditioner provides a fresh air
option, keep the fresh-air intake closed to prevent
smoke from getting inside. Make sure that the fil-
ter is clean enough to allow good airflow indoors.
Do not vacuum anywhere in the house, unless
using a HEPA-filter equipped vacuum.
Do not smoke or burn anything, including can-
dles or incense, anywhere in the house.
Keep the room clean by damp mopping or dust-
ing with a damp cloth.
Long-term smoke events usually have periods
when the air is better. When air quality improves,
even temporarily, air out your home to reduce
indoor air pollution.
People in homes that are too warm to stay inside
with the windows closed or who are at-risk of
smoke-related health effects should seek shel-
ter elsewhere. Keep in mind that many particles
will enter the home even if all of these steps are
taken.
For additional information, see the EPA website
Create a Clean Room to Protect Indoor .Air Qual-
ity During a. Wildfire.
Cleaner air shelters and cleaner
air spaces
Public health officials in areas at risk from wildfire
smoke episodes should identify and evaluate public
spaces where people can seek relief from wildfire
smoke. For the purposes of this guide, these public
spaces are defined as either cleaner air shelters or
cleaner air spaces. People should be made aware
that driving to and from a public shelter or cleaner
air space for short-term relief and the stress of
evacuating for an extended stay in a shelter can also
have health consequences. Therefore, whether to
create a clean room at home or leave for a public
shelter or cleaner air space will depend on factors
that the individual must assess.
Cleaner air shelters
Cleaner air shelters are public spaces for people
who are displaced by wildfire or smoke. People
who take refuge in these shelters may only need
to stay overnight or may need the shelter for
extended periods (days or even weeks). Some
examples of cleaner air shelters are school
gymnasiums, buildings at public fairgrounds, and
civic auditoriums. A cleaner air shelter may also be
considered an evacuation shelter but be aware that
not all evacuation centers provide cleaner air for the
occupants. Therefore, public health officials in areas
at risk from wildfire smoke episodes should identify
and evaluate public spaces where people can shelter
from wildfire smoke well in advance of fire season.
Guidance for identifying or setting up a cleaner air
shelter is provided in .Appendix B.
Cleaner air spaces
During severe smoke events, it is often impractical or
impossible for people to set up a clean room in their
homes. Individuals who cannot create an adequate
clean room should be encouraged to seek out cleaner
air spaces located in their communities for periods of
respite from the smoke. People can find temporary
relief from smoke, heat, or cold at public cleaner air
25
-------
spaces for several hours, or perhaps for the better
part of a day; however, many of these commercial
spaces and public facilities are unlikely to be open at
night. Examples of cleaner air spaces could include
libraries, museums, shopping malls, theaters, sports
arenas, senior centers, and any indoor area with
effective particle filtration and air conditioning.
Inside vehicles
Individuals can reduce the amount of smoke in their
vehicles by keeping the windows and vents closed,
and, if available, operating the air conditioning in
"recirculate" mode. However, in hot weather, a car's
interior can heat up very quickly to temperatures
that far exceed that outdoors and heat stress or heat
exhaustion can result. Children and pets should
never be left unattended in a vehicle with the
windows closed. The ventilation systems of older
cars typically remove a small portion of the particles
coming in from outside. Newer models may have
better air filters that remove more particles from the
air, but the vehicle owner should not assume that
they will get the same level of protection they would
get from a dedicated clean room or cleaner air space.
Most vehicles can recirculate the inside air, which will
help keep the particle levels lower.
Drivers should check the owner's manual and
assure that the system is set correctly to minimize
entry of outdoor smoke and particles. However,
studies have shown that carbon dioxide levels can
quickly accumulate to very high levels (possibly
exceeding 2500 parts per million) in newer cars
due to occupants' exhaled breath when vents and
windows are closed and the recirculation setting is
used (Fruin et al. 2011, Hudda and Fruin 2018, Lee
and Zhu 2014). Therefore, if driving a recent model
vehicle for more than a short period of time, it may
be a good idea to briefly open windows or vents
occasionally when smoke levels are low to avoid the
build-up of carbon dioxide. Finally, vehicles should
not be used as a shelter, but rather as a means of
transportation to indoor locations with cleaner air.
Respiratory protection for wildfire
smoke and ash
Respiratory protection (commonly referred to
as "masks") can be useful for reducing personal
inhalation of wildfire smoke or ash. Respirators are
widely available and offer some protection for adults
if selected and used properly, although the public
should be advised to take more effective measures
first to limit their exposures. Information provided
in this section describes selection and proper use
of tight-fitting particulate respirators certified by
the National Institute for Occupational Safety and
Health (NIOSH).
Drawbacks to recommending the use of respirators
include the possibility that users will select the wrong
type or use them incorrectly. A stand-alone factsheet,
'Protect Your LutiP's from Wildfire Smoke or Ash.
has been designed for the public and includes links
to other resources. The use of respiratory protection
without first ensuring that no medical conditions
exist that would make use of respiratory protection
a risk or first providing users with "fit tests" to
ensure a reliable seal to the face is not ideal although
inevitable in the case of public wildfire smoke
exposure. A fit test is a procedure that quantitatively
or qualitatively evaluates the fit of a specific model
and size of respirator on an individual and is required
in workplace settings. However, the respirators
described in this section are available in multiple sizes
and are likely to provide some protection to users
who can achieve a reasonably close fit to the face,
even without fit testing.
Respirators described in this section would also help
to protect the public involved in cleaning up fire
ash. There is additional guidance in this document
on wildfire ash, and a factsheet for the public on
cleaning up ash, Protect Yourself from .Ash.
Respiratory protection use in workplace situations
is beyond the scope of this section, see Chapter
5, P ro tec ting Ou tdoo r Wo rke rs. Employers who
anticipate that their workers may need to wear
respiratory protection are expected to put in place
a full respiratory protection program prior to use.
26
-------
In emergency situations, employers should consult
the applicable Occupational Safety and Health
Administration (OSHA) program for current
guidance. Where respirator use is not required by
OSHA regulations or by the employer, the employer
may provide respirators at the request of employees
Or permit employees to use their own respirators, if
the employer determines that such respirator use will
not in itself create a hazard and provides some basic
information about proper use and the limitations of
respirators.
Children and respirator use
Respirators are not made to fit: children and will not
protect tliem from breathing wildfire smoke. Children
are especially at risk from exposure to wildfire smoke
because their lungs are still developing. Reduce
children's exposure to wildfire smoke by checking
air quality, keeping them indoors, creating a clean air
room, and being ready to evacuate if necessary. See
also the factsheet Protecting Children from Wildfire
Smoke or Ash.
\ K )SI I does not currently certify respirators for
children. As new research findings on efficacy
become available, guidance by U.S. government
agencies may be issued on the proper use of
respirators by older children.
Who may need to wear a respirator
The most effective action the public can take to
reduce the risk of health effects from inhalation
of wildfire smoke or ash is to stay indoors or limit
the time spent outdoors during wildfire smoke
emergencies. People at higher risk of adverse effects,
such as those with heart or lung disease and older
adults, should check with their health care providers
before using a respirator, since using a respirator
can make it harder to breathe. If the smoke event
is expected to be prolonged, these groups should
consider temporary relocation out Ot the smoky area:.
People who must be outdoors for extended periods
of time in smoky air or in an ash-covered area may
benefit from using tight-fitting, NIOSH-approved
N95 or PI00 respirators to reduce their exposures.
People experiencing health effects from a smoky
environment, even if indoors, may also benefit from
using N95 or P100 respirators if they cannot move
to locations with better air quality or take other steps
to clean their indoor air.
For people who wish to wear respirators, learning
how to select respirators and use them correctly is
important for achieving the best protection possible.
Figure 4.Two types of N95 disposable particulate respirators. Note the presence and placement of the two straps
above and below the ears. Photos courtesy of the California Department of Public Health
27
-------
Choosing the correct respirator
Tight-fitting "particulate" respirators are designed
to capture or filter out particles from contaminated
air before the user can breathe them in. A "filtering
facepiece" respirator, commonly called a disposable
N95 or P100 respirator, has two straps and a
facepiece made entirely of filtering material (Figure
4). Respirators must be certified by NIOSH, and the
words "NIOSH" and either "N95" or "PI00" will
be printed on the facepiece by the manufacturer. The
user should select a size and model that fits over the
nose and under the chin and seals tightly to the face.
Any leakage around the face seal causes unfiltered
air to enter and be inhaled by the wearer, reducing
or eliminating the ability of the respirator to provide
protection. A good seal is not possible if the user
has a beard or other excess facial hair where the
respirator seals to the face.
The numbers "95" and "100" on a respirator
facepiece indicate that the filter material captures
95% or 99.97%, respectively, of particles passing
through it when tested using particles 0.3 micron in
diameter that are the hardest to capture. However,
when used by the public without individual user fit
testing, there is likely little difference in effectiveness
between N95 and P100 respirators, as leakage
around the face seal will be a more significant factor
determining effectiveness than filtration efficiency.
"N" indicates filter material that is not resistant to
degradation in the presence of oil mist; "P" identifies
filters that are resistant. In environments where
smoke or ash are present, N95 or PI00 respirators
can be used. Both types can be found in retail
pharmacies, in hardware and home repair stores,
or online. NIOSH-approved respirators with filters
designated as N99, N100, R95, P95, and P99 are far
less common, but would also be appropriate.
Other non-disposable NIOSH-certified respirators,
such as elastomeric half-masks, can also be used
for wildfire smoke or ash. They have a tight-
fitting, flexible, re-useable half-mask facepiece
and replaceable filters or cartridges; these provide
similar protection from particles when they are used
with N95 or PI00 particulate filters. This type of
respirator may also be purchased with a combination
filter and organic vapor cartridge, which can reduce
exposure to irritating gases in smoke, such as
aldehydes. (Disposable N95 or P100 respirators
remove only particles, not gases or vapors.)
How to use a tight-fitting respirator
To get a secure fit, a respirator user should put the
facepiece over the nose and under the chin and
position one strap at the back of the neck below
the ears, and the other at the crown or top of the
head, above the ears. Incorrect strap placement
is a common problem with untrained respirator
users and may compromise the face seal and reduce
effectiveness.
Users must be clean-shaven where the respirator
touches the skin. A good face seal is not possible
with facial hair. Care should be taken so that hair,
eyeglasses, or other objects do not interfere with the
seal of the respirator to the face.
Some N95 or P100 respirators have a metal nose
clip that should be pinched around the bridge of
the nose to fit securely. The user should follow
any instructions provided by the manufacturer for
checking for a tight face seal.
Disposable respirators should be discarded when
they become dirty, wet, deformed in shape, or when
it gets harder to breathe through them.
Possible risks from wearing a respirator
Wearing a respirator can make it harder to breathe.
Public health officials should encourage members
of the public who have heart or lung problems to
consult their health care provider before using a
respirator.
Anyone who has difficulty breathing while wearing a
respirator, feels dizzy, faint, or claustrophobic or has
other symptoms, should remove it and go to a place
with cleaner air.
Wearing a respirator, especially if a person is
physically active or in a hot environment, may
increase the risk of heat-related illness. Users should
take periodic breaks from physical activity or, if
possible, rest in a location with cleaner air where the
28
-------
Figure 5. A one-strap paper mask is not a respirator
and provides little or no protection from smoke
particles. Photo courtesy of the California Department
of Public Health
respirator can be removed. Rest in a cooler area such
as in shade and adequate hydration are important for
heat illness prevention, as is gradually acclimating
to physical activity in hot locations. Symptoms such
as dizziness, nausea, or feeling faint should prompt
the user to remove the respirator and seek medical
attention or emergency care as appropriate.
Certain "masks" do not provide protection
The public should be cautioned that masks with
one-strap nuisance dust masks (Figure 5) or surgical
or procedure masks with two straps that loop
around the ears (Figure 6) are not respirators. They
are not designed to seal tightly to the face and will
not provide protection from wildfire smoke or ash.
Bandanas (damp or dry), handkerchiefs, and tissues
held over the mouth and nose also should not be
relied On for protection.
Handling respirator shortages
In a large-scale wildfire smoke emergency, local
supplies of N95 and P100 respirators may become
limited or exhausted. Local health officials might
want to monitor respirator availability and consider
Figure 6. A surgical mask is designed to capture
infectious particles generated by the wearer, is not a
respirator, and provides little or no protection from
smoke particles. Photo courtesy of the California
Department of Public Health
ways to increase the supply it necessary. Extra
respirators may be available from regional or
state stockpiles of personal protective equipment,
or directly from respirator manufacturers and
distributors of safety equipment.
Respiratory protection resources
An excellent (but fairly technical) NIOSH article,
Non-occupational Uses of Respiratory Protection -
What Public Health Organizations and Users Need
to Know discusses common mistakes of untrained
users as well as best practices and provides references
to relevant studies.
NIOSH has a searchable website entitled Approved
N95 Particulate Filtering Facepiece Respirators
that lists NIOSH-approved N95s alphabetically by
manufacturer.
Public health officials can find additional information
on the NIOSH Respirator Trusted-Source
Information website.
29
-------
Avoiding smoky periods
Smoke levels from wildfires often change
substantially over the course of the day, so there may
be opportunities for the public to plan necessary
trips outside at times of day that avoid the worst
periods of smoke. Ground-level smoke impacts are
often forecasted and posted on state smoke blogs
in states that use these outreach tools. For example,
officials in California. Idaho. Oregon. Washington,
currently post forecasts to smoke blogs during
fire season. Forecasts can also be found on the
ificiweb site by specific named wildfire incidents
and at the Wildland Fire Air Quality Response
Program page (https:/ /wildlatidfiresfiioke.tiet).
For communities near active wildfires, smoke
impacts often follow a pattern such as nighttime
smoke draining downhill and settling into valleys
before lifting out the next day. Communities farther
downwind of a fire may see smoke arrive in the mid-
to-late afternoon and occasionally linger overnight.
Either way, it is sometimes possible for people to
plan their days around the smokiest times in order
to minimize exposure. Public health officials can
recommend the use of NowCast AQI (current air
quality in terms of the AQI) values from nearby or
representative monitors to help people identify and
avoid the smokiest times of day (see). Visual range-
based estimation can be used if no monitoring is
representative of the impact areas. Links to smoke
forecasts can be disseminated to provide daily
smoke impact patterns in your local Public Service
Announcements (PSAs) (see Chapter 5). Chaper 5
describes the Wildland Fire Air Quality Response
Program and provides an example of a smoke
forecast from a large wildfire.
Closures
The decision to close schools, curtail business
activities, or cancel public events is made at the local
level and will depend upon predicted smoke levels
and other local conditions. Check to see if your state
or local air quality or public health agencies have
developed guidance that local health officials can
reference when trying to evaluate when or where
closures should occur. Other factors to consider are
whether pollutant levels inside schools and businesses
are likely to be similar to or lower than those in
homes. Children's physical activity may be better
controlled in schools than in homes. On the other
hand, smoky conditions may make travel to school
hazardous. In many areas, it will not be practical
to close businesses and schools, although partial
closures may be beneficial. Closures and cancellations
can target specific groups (e.g., the at-risk groups
described earlier) or specific high-risk activities,
such as outdoor sporting events and practices.
Curtailing outside activities can reduce exposures,
as can encouraging people to stay inside and restrict
physical activity.
Evacuation
The most common reason for evacuation during a
wildfire is the direct threat of engulfment by the fire,
rather than exposure to smoke. Leaving an area of
thick smoke may be a good protective measure for
members of at-risk groups, but it is often difficult
to predict the duration, intensity, and direction of
smoke, making this an unattractive option to many
people. There is stress associated with evacuation and
most people do not want to leave their homes. Even
if smoky conditions are expected to continue for
weeks, it may not be feasible for a large percentage
of the affected population to evacuate. Moreover,
the process of evacuation can entail serious risks,
particularly if poor visibility makes driving hazardous.
In these situations, the risks posed by driving need
to be weighed against the potential benefits of
evacuation. Therefore, in areas where fires are likely
to occur, public health officials are encouraged to
develop plans to help at-risk groups shelter locally.
Where individuals are evacuated to a common center
because of fire danger, public health officials need
to pay particular attention to the potential for smoke
to affect the evacuation center itself. It is not always
possible to locate evacuation centers far away from
smoky areas, or to expect that evacuees will be able
to take the steps necessary to reduce their exposures
in their new surroundings. Public health officials
should consider informing incident commanders
if this situation could arise and supplying evacuees
with information and materials to further reduce
30
-------
exposures, including provision of a cleaner air
shelter within the evacuation center, if possible, as
well as other means of respiratory protection. (See
"Respiratory Protection" above.) It is important to
consider smoke levels when allowing those evacuated
for fire safety reasons to return to their homes.
Medical capability (from available transport to urgent
care and hospital capacity) to address smoke induced
medical situations should be assessed if smoke levels
are predicted to be high. Additionally, the smoke
from smoldering natural and (if structures are burned
in fires) possibly manmade materials pose ongoing
hazards that should be considered.
Summary of strategies to reduce
smoke exposure
The public should be encouraged to prepare to
minimize trips out of the home before fire season
arrives by having food and medicine on hand to last
several days. Foods stored for use during a smoke
event should not require frying or broiling, since
these activities can add particles to indoor air.
When smoky conditions are expected, people
can pursue a number of strategies to reduce their
exposure. Those with moderate to severe heart or
lung disease might consider staying with relatives or
friends who live away from the smoke impact area.
If smoke is already present in substantial quantities,
such individuals may want to evaluate whether
their exposure during evacuation would be greater
than staying at home and using other precautions
described above. Depending on how sensitive they
are to smoke, as smoke levels increase it may be
appropriate for some people to stay in a clean room
in the home, relocate temporarily to a cleaner air
shelter, or to leave the area entirely if it is possible
and safe to do so.
Everyone in a smoky area should avoid strenuous
work or outdoor exercise to the greatest extent
possible. They should avoid driving or if driving
is necessary, run the air conditioner on recirculate
mode to avoid drawing smoky air into the car.
Smoke can also impair roadway visibility making
driving hazardous. Guidance on protecting outdoor
workers from wildfire smoke has been developed
by the California Division of Occupational Safety
and Health (Cal/OSH..A.). More information about
the protection of outdoor workers can be found in
Chapter 5.
Closing up a home by shutting windows and doors
can give some protection from smoke. Most air
conditioners are designed by default to recirculate
indoor air. Systems that have both "outdoor air" and
"recirculate" settings need to be set on "recirculate"
during fire/smoke events to prevent smoke-laden air
from being drawn into the building (note: this does
not apply to HVAC systems in office and commercial
buildings; see .Appendix D). Additional protection in
homes can be achieved by operating properly-sized
air cleaners and upgrading the filtration efficiency of
air filters in central air conditioning systems. High-
efficiency filters (rated at MERV 13 or higher) should
be installed when feasible. When filters have been
upgraded, central air conditioning fans can be set to
operate continuously during a wildfire event, and not
cycle on and off, although this will increase energy
use and costs.
Once people have closed up the building in which
they live, they should avoid strenuous activity, which
can make them breathe harder and faster. They
should drink plenty of fluids to keep their respiratory
membranes moist. Vacuuming (except with HEPA
filter-equipped vacuums) should also be avoided,
since most vacuum cleaners disperse very fine dust
into the air.
Smoke levels can change substantially over the course
of the day, so it may be possible to plan your day
around the smokiest times to minimize exposure
using tools and information in this Guide.
NIOSH-approved disposable particulate respirators
(e.g., N95 or PI00) available in hardware stores
and online provide some level of protection from
exposure to particles in smoke as long as a close-
fitting model and size is selected, and they are used
properly. One-strap paper masks, surgical masks, or
other face coverings are not recommended since they
provide little or no protection.
31
-------
IV. COMMUNICATING AIR
QUALDTY CONDITIONS
DURING SMOKE EVENTS
32
-------
An important goal of air quality monitoring during
a wildfire smoke event is to relay information to
the public in a timely manner so people can make
decisions about how to protect their health. Filter-
based PM monitors take days to process, but
continuous PM monitors give a near real-time reading
of PM concentrations every hour. This is an estimate
of the 24-hour average PM AQI using the NowCast
algorithm discussed below. Areas without continuous
PM monitors may be able to get temporary, portable
monitors through their federal, state, tribal, or
local air quality agencies or the U.S. Forest Service,
especially when associated with a wildfire incident
with an assigned Air Resource Advisor.
Air Quality Index
The Air Quality Index, or AQI, is a nationally
uniform index promulgated by the EPA for
reporting and forecasting daily air quality across
the country. It is used to report information about
the most common ambient air pollutants, including
those most relevant to wildfire smoke: particulate
matter (PM05 or PM10) and ozone. The AQI tells
the public how clean or polluted the air is using
standard descriptors (Good, Moderate, Unhealthy
for Sensitive Groups, Unhealthy, Very Unhealthy,
and Hazardous). The index converts ambient
concentrations (jjg/m3 or ppb) to a number and
category more easily understood by the public. The
AQI uses a normalized scale from 0 to 500 and
provides associated health-based descriptors for each
category. An AQI value of 100 corresponds to the
level of the short-term National Ambient Ar Quality
Standard for a given pollutant. An advantage of
using the AQI value over the concentration (|ig/m3)
for particulate matter is that the AQI value of 100
represents a clear demarcation between satisfactory
and unhealthy air quality, at least with reference
to the national standard, which is established at a
level that will protect public health, including the
health of at-risk groups. When AQI values exceed
100, air quality is considered to be unhealthy, at first
for members of at-risk groups (in the Air Quality
Index, the term "sensitive groups" is used), then for
everyone as AQI values increase. Another advantage
Air Quality
Less variable More variable
M ~
~ 12-hour average ~ 3-hour average
NowCast J
Figure 7. Overall concept of the NowCast
is that the AQI provides actionable activity advice for
at-risk groups, as well as the general public, to reduce
smoke exposure.
AirNow
The AirNow website, at www.alrnow.gov is a multi-
agency web site run by EPA that reports air quality
using the AQI. The AirNow program accepts, stores,
and displays data provided by state, local, and federal
air quality agencies. Agencies submit continuous PM
data to AirNow from over 1,200 PM05 monitors and
500 PM10 monitors, plus temporary monitors, on an
hourly basis. These data are available to the public via
an interactive map on airnow.gov and through email
notifications, widgets, and smart-phone apps. Media
outlets and web developers can also access the data
through AirNow's Application Program Interface
(alrnowapi.org). See Appendix C for a description of
AirNow-Tech, a website that air quality organizations
use for data analysis and management, including the
Navigator tool for wildfire evaluation.
NowCast. The AQI for PM05 and PM10 is a daily
(midnight to midnight) 24-hour average, so hourly
reporting requires a methodology called the NowCast
to estimate the 24-hour AQI for each hour. The
reported hourly value is what AirNow calls "current
air quality."
The NowCast method for reporting each hour's
current conditions is responsive to rapidly changing
air quality such as occurs during a wildfire (Figure
7) The NowCast uses a weighted average of the
previous 12 hours. When air quality is changing
rapidly, the most recent hours are weighted more
heavily. A longer average, approaching 12 hours,
33
-------
Local Air Quality
Zip Code: Zip Code I Go
Sunnyside
Data and Forecasts courtesy of:
Northwest Clean Air Agency, Olympic Region Clean Air Agency, Puget Sound Clean Air Agen>
Forecast AQI Loop More Maps
Current Conditions
Air Quality Index (AQI)
observed at 7:00 PDT
76 Moderate
Health Message: Unusually sensitive people should consider
reducing prolonged or heavy exertion.
iVofe: Vafd/as above 500 are considered Beyond the AQI. Follow recommendations for
the Hazardous category. Additional information on reducing exposure to extreme/y
high levels of particle pollution is -available here,
AQI - Pollutant Details
Particles (PM2.5)
Moderate
Figure 8. Sample AirNow current air quality data, map, and AQI values
is used when air quality is stable. The NowCast
helps ensure that AQI maps and data on AirNow
more closely match what people actually experience
outdoors (Figure 8).
Fires: current conditions map. The wildfire map
page on airnow.gov (https: / /aim ow.gov /index.
ctm?action=topics.smoke wildfires) is a one-stop
place where the public can assess current wildfire
activity and air quality conditions across the country
(Figure 9). The interactive map is a joint effort of
the U.S. Forest Service, EPA, and state and local
air quality agencies. The map displays several layers
such as the current network of PM,5 monitors as
well as any temporary I'M. monitors deployed for
a fire event. The monitors are shown in the color of
their current AQI value. Other layers include active
wildfires and smoke plumes. In addition, the page has
important links to state advisories and smoke blogs,
information about smoke and health, and a variety of
external web resources pertaining to wildfires.
Enviroflash. Offered in many areas around the
country, EnviroFlash is a system that sends the daily
air quality forecast by email to anyone who signs up.
It can also be used by state and local agencies to send
Search.
Local Air Quality Conditions
Zip Code: Go State: Alabama
Fires: Current Conditions
San Die9ฐ|ฉ ^ ^lexiฃj O
Figure 9. Sample AirNow Fires: Current Conditions map
Cur row
Monday^
34
-------
an email alert during an event such as a fire, including
suggested safety measures which are included when
air quality is unhealthy This service is provided by
the state or local environmental agency and EPA.
Information about Enviroflash is available at http:/ /
www.enviroflash.info.
Outdoor activity guidance. The Air Quality
and Outdoor Activity Guidance for Schools table,
developed by the EPA and the Centers for Disease
Control and Prevention (CDC), shows when and
how to modify outdoor physical activity based on the
AQL This guidance can help protect the health of all
children, including teenagers, who are more sensitive
than adults to air pollution. The activity guidance
can be found at: https:/ /www3.epa.gov/a.irnow/
flag/school-cha.rt-2014.pdf. A similar guide for PM
that includes activities for all ages can be found here:
https: / /www^.epa.gov /airnow/air-quality-guide
pm 20lS.pdh
Air Quality Flag Program. The activity guidance
can be used with the Air Quality Flag Program. The
Air Quality Flag Program (https: / /a.irnow7.gov/index.
cfm?a.ction=flag program-index) is a visual way to
alert schools and other organizations to the local air
quality forecast. Seeing the flag alerts people about
the local air quality so that they can take actions to
protect their health.
Interagency Wildland Fire Air Quality
Response Program and Air Resource
Advisors
The Interagency Wildland Fire Air Quality Response
Program (IWFAQRP, https://wildlandfiresmoke.
net) is an interagency effort led by the U.S. Forest
Service to provide enhanced information to wildfire
incidents, agencies, and communities dealing with
smoke issues. This need for predicting smoke
impacts associated with wildfires and the role of
the IWFAQRP was recognized and authorized
by Congress in 2019. The IWFAQRP has several
components including tools for enhanced monitoring
and modeling of smoke; creating consistent smoke
Outlook forecasts in a simple format for sharing
Planning Section
Satellite
Products
Smoke
Monitors
News/Social Media
Smoke
Models
Web
Tools
AIR
Resource
Advisor
Local Air Quality/Public Health
Agencies/EPA
PUBLIC
Incident
Decisions
Field
Reports
FBAN
IMET
PSC
SOF
PIO
Figure 10. Elements of the Wildland Fire Air Quality
Response Program supporting an Air Resource Advisor
assigned to an Incident Management Team responding
to a wildfire. Air Resource Advisors work under the
Planning Section of an Incident Management Team with
direct interaction with the Planning Section Chief (PSC),
Incident Meteorologist (IMET), Fire Behavior Analyst
(FBAN), Safety Officer (SOF), and Public Information
Officer (PIO),
with the public; and messaging in conjunction with
state, tribal, and local air quality agencies as well
as health departments. Much of this work is done
through the deployment of technical specialists
called Air Resource Advisors (ARAs) working with
either wildfire Incident Management Teams (IMT) or
directly with land management agencies that request
them as part of wildland fire management efforts.
Deployed AR As are a good resource for gaining
insight into expected fire growth, emissions, and
impacts. An ARA generally works in the planning
section of the IMT and consults closely with experts
in fire weather and fire behavior. ARAs are trained
to use a variety of smoke dispersion models in
conjunction with air quality monitoring to help
build smoke forecasts and information products for
the public.
35
-------
''*>5 Smoke Outlook for 6/14 - 6/15
SW Colorado 416 and Burro Fires
Issued at: 2018-06-14 14:35 UTC
Outlook for SW Colorado
Fire
416 Fire is at about 32,000 acres. 15% containment. Burro Fire
is about 3.000 acres at 0% containment. Predicted
thunderstorms may bring strong outflow winds and increase
the potential for extreme fire behavior.
Smoke
Durango and Bondad should get a reprieve from smoke today.
Hermosa will see smoke impacts at varying levels throughout
today. Silverton and Lake City will see greater smoke impacts
today and tomorrow. Vallecito may see smoke drifting in late
this afternoon as well tomorrow morning. Dolores and Aztec
should not see much smoke impacts today.
One way to reduce smoke exposure
Consider using a HEPA air filtration unit to help keep a room in
your home less smoky. For more information see:
https://www.missoulaclimate.org/hepa-air-filtration.html
Daily AQI Forecast for )un 14. 2018
Silverton Q
Dolores(
* -
Durangoฎ
Bondadn
Hermosa
Vallecito
Aztec Q
I armvlcn
Station
Yesterday
hourly
Wed
6/13
Forecast
Comment for Today Thu, Jun 14
Thu Fri
6/14 6/15
Bondad
6a f&:r\ Gp
IHKlillli,
Generally clear today, smoke returning tomorrow morning before clearing
around noon.
0
Oolores
4MMSB1 -
o
Generally clear today
Hermosa m
mmiinif.
Heavy smoke drift mid-afternoon, some clearing tonight, returning at heavy
levels early tomorrow morning, persisting to noon.
Generally clear today with heavy smoke retuminq early tomorrow morning
A
A
41
Figure 11. Example smoke outlook (partially shown) produced by an Air Resource Advisor assigned to the 416 Fire. Current
smoke outlooks are available at https://wildlandfiresmoke.net/outlooks.
Air Resource Advisors use a national cache of
deployable smoke monitors (typically E-SAMPTERS
and I I B WIS with real-time telemetry capability)
during wildland fire incidents to provide ground
information to communities lacking existing
monitoring capabilities* Enhanced smoke modeling
including high resolution grids over affected areas
can be requested of the National Weather Service
by an ARA. Air Resource Advisor deployments
and contact information are available at https:/ /
wildla.ndfiresmoke.net. ARA-developed outlooks are
available at https:/ Ayildlandfiresmoke.net/outlooks.
A collection of IWFAQRP related tools developed
by the LIS. Forest Service Pacific Northwest Research
Station's AirFire Team are shown in Appendix C and
are available at https://tools.airfire.org.
New monitoring and air quality
estimation technologies - a caution
In recent years, technology development has
expanded the variety of information available about
air quality. These emerging technologies include
miniaturized PM05 sensors stationed in outdoor or
indoor environments, mobile air quality monitoring
systems, air quality models that can estimate
36
-------
concentrations in locations without nearby monitors,
and data fusion products that blend together
observational data and models. Still in a research
phase, but likely to expand over time, are personal
wearable devices or apps designed to estimate an
individual's exposure to PM25.
In many areas, these emerging technologies and their
data are already part of the wildfire smoke dialogue.
During a wildfire smoke event, communities lacking
a centrally-located PM25 monitor may rely on sensors
as a primary source of air quality information.
Citizens, especially those in at-risk groups, might
make decisions based on localized estimates
from emerging technologies to mitigate their
smoke exposure.
Nevertheless, these data must still be regarded with
caution. At this writing there are still many unknowns
concerning the precision, accuracy, and reliability of
readings from sensors, air quality models, and data
fusion products, especially in extreme conditions like
a wildfire smoke event. Although the technology is
improving, it is important to recognize the limitation
of using these as stand-alone devices and data
products without a reference monitor nearby to
evaluate the new technology's performance.
In cases where ARA-implemented monitors or
official air quality network monitors exist and
emerging technology is implemented, conflicts in air
quality information may result. This does not mean
that either information set is necessarily wrong, but
reflects differences in the locations measured, how
data are averaged, or how the AQI is computed. An
additional cause for disagreement may be error in the
measurement device or data fusion product.
Therefore, sensor data, models, and data fusion
products should be considered as supplements to
a larger package of information to make better
informed decisions on smoke messaging. Comparing
sensor data, models, or data fusion products with
nearby reference monitors can help the public
official understand how to consider this information
in their assessment of smoke conditions and
communications. These new sources of data may
provide important information on the trends of
PM25, but they need to be put into context with the
help of nearby regulatory monitors or short-term
monitors implemented by an ARA, AQI estimates,
satellite data, and from daily ARA Smoke Outlooks.
Using visual range to assess smoke levels
in the interior western United States
Many communities do not have access to continuous
PM monitoring and may need other ways to
evaluate local air quality. Visual range (i.e., how far
can be seen?), like other instantaneous monitoring
approaches, can inform and help the public respond
to smoky conditions. This is true even in areas
that have continuous monitors, because smoke
concentrations can vary widely within a couple of
miles and can change rapidly.
Basic Approach:
To determine visual range, one must:
use this method only during daylight hours,
avoiding sunrise and sunset,
use this method only if relative humidity is less
than 65%,
focus on the darkest object (e.g., black is better
than green),
determine the limit of visual range by looking
for targets at known distances (miles), (the visible
range is the point at which even high-contrast
objects (e.g., a dark forested mountain viewed
against the sky at noon) totally disappear, and
after determining visual range in miles, use Table
3 to identify actions to take to reduce
exposure.
Often, it is difficult to assess "the point at which even
high-contrast objects (e.g., a dark forested mountain
viewed against the sky at noon) totally disappear."
Instead, it may be more useful to use known
landmarks at a given distance away to assess possible
visual ranges. For example, target A is 2 miles away
and visible, but target B, which is 4 miles away, is
not visible Therefore the visual range is somewhere
37
-------
Table 3.Visual range and actions to take to reduce smoke exposure when wildfire smoke is
in the air.**
Distance
seen
Population Type
OR
Specific Illness
A Healthy Adult,
Teenager, or Older Child
Older adults (>65 years),
Pregnant, or A Young Child
Asthma, Respiratory Illness, Lung or Heart
Disease
> 10 miles
Watch for changing
conditions and moderate
outdoor activities based on
personal sensitivity
Watch for changing conditions and moderate outdoor
activities based on personal sensitivity
5-10 miles
Moderate outdoor activity
Minimize or avoid outdoor activity
< 5 miles
Minimize or avoid outdoor
activity
Stay inside or in a location with good air quality
1 Sensitivity to smoke can vary greatly from person to person and individuals can become more sensitive to smoke after extended periods of exposure. Individuals should
pay attention to the advice of a medical professional or local health officials and adjust activity accordingly to their particular tolerance or sensitivity.
between 2 miles and 4 miles. Use Table 3 to identify
the range of actions to consider to reduce smoke
exposure.
Western United States: An important caveat is that
the above visual range categories only apply in dry
air conditions typically found in the interior west and
inland of coastal areas. The combination of water
and particulate matter in the atmosphere dramatically
reduces visibility therefore this method of estimation
should not be used when relative humidity is greater
than 65%.
Eastern United States and Higher Humidity
Locations: Until this approach can be assessed
for humid conditions, individuals may have to rely
on common sense in estimating smoke conditions
(e.g., mild, moderate, heavy smoke) and the kinds of
protective actions that might be necessary to address
personal response to the smoke.
Other Considerations: This method of estimating
a visual range also contains much uncertainty (as
discussed in Malm and Schichtel, 2013), further
strengthening the need to use personal judgment
when assessing smoke conditions. Smoke
concentrations vary substantially from minute to
minute. By comparison, continuous monitoring
devices average their measurements over 1, 3, or
even 24 hours, so what is seen at a particular moment
may not be representative of the average reported
at a nearby monitor. More uncertainty stems from
sighting on non-black bodies (e.g., green forested
landmarks, snow-covered peaks), difficulty at judging
when an object is just barely visible, variations in the
atmosphere and thickness of the smoke across the
line of sight, and assuming the atmosphere remains
constant after using an instantaneous "look" to assess
conditions. Another commonly occurring problem
with this method is that the concentration along the
visual path is not constant, for example, when there is
little smoke at the surface, but a thick layer of smoke
aloft and the reference point being used is above that
smoke layer such that the viewer is looking through
it. In such cases these methods would be invalid.
This method is also not effective in early morning or
twilight hours when the sun is low on the horizon.
The bottom line is that, no matter how far one can
see, it is always prudent to take measures such as
those presented in this Guide to protect oneself if
smoke exposure is a concern.
38
-------
V. RECOMMENDATIONS
FOR PUBLIC HEALTH
ACTIONS
39
-------
This chapter includes specific guidance to public
health officials on actions to take to protect the pub-
lic and to advise the public during a wildfire event,
preparations to make before fires occur, and recom-
mendations for cleaning up after a fire. Because there
are many factors to consider during a wildfire event,
these recommendations should be adapted for each
specific situation.
Public advisories arid protective
measures
Areas with established air quality programs typically
have a communication plan for alerting the public
about air pollution events. A communication plan
includes details on who should be given specific
information, when that information should be
delivered, and what communication channels
to use to deliver the information. An effective
communication plan anticipates what information
will need to be communicated to specific audience
segments, such as schools or nursing homes.
One approach is to refer the public to the AirNow
website (www.airnow.pov). which is used by states
and most communities across the country. Methods
for sharing information include state smoke blogs,
websites, hotlines, press releases, and social media, as
well as emails and faxes to interested parties (such as
sports team coaches and daycare providers). Some
rural areas have used door-to-door dissemination
of a visibility index (see Table 3) and the associated
health effects.
Table 4 provides a general list of health effects and
cautionary statements about altering behavior that
can be used in public advisories. The advisories are
based on the AQI, as well as on experience and
evidence from fire situations. If only PMW measurements
are available during smoky conditions, it can be assumed that
the PM is composed primarily of fine particles (PM2J, and
therefore theAQI and associated cautionary statements and
advisories forPM2S may be used.
'.Table 5 provides guidance to public health officials
about measures that can be taken to protect
public health at different AQI categories and the
corresponding ambient PM levels. This information
is intended to help health officials, the media, and
the general public make decisions about appropriate
strategies to mitigate exposure to smoke. As
noted earlier, the official AQI value for PM25 for
the previous day is a 24-hour average of PM25
concentrations measured from midnight to midnight.
The real-time AQI for PM25 reported by the media
and on AirNow is the hourly estimate of the 24-
hour AQI based on the NowCast. Although Table 5
provides ambient PM2 concentrations and the AQI
values and descriptors associated with the categories
(e.g., Good, Moderate), concurrent publication
of both the AQI values and the ambient PM25
concentrations (in [j.g/m3) to describe air quality may
lead to confusion among members of the public. To
avoid such confusion, it may be preferable to publish
just the AQI values.
Protecting children
Protecting children is always a high priority in smoke
events. The factsheet .Air Quality and Outdoor
Physical Activity Guidance lor Schools, developed
jointly by EPA and CDC, provides guidelines about
when and how to modify outdoor physical activity
based on the AQI. If a smoke event is forecasted,
local officials should prepare to implement the
guidance, including assessing the availability of
indoor spaces with good indoor air quality for
children to be active.
As air quality worsens or is projected to worsen,
additional protective measures may become
necessary. These measures could range from allowing
children with asthma or other medical conditions that
place them at greater risk from smoke to stay home,
to closing schools entirely. Several location- and
event-specific factors should be considered in making
these decisions. Some of these factors include the
forecast duration of the event, the relative indoor
air quality of the homes and schools in the area, and
the ability to transport children safely to and from
school. In some locations, indoor air quality may
be better in schools than in local housing, making
school closure less beneficial from a public health
perspective. Indoor air quality in schools should be
assessed before the start of the fire season to assist in
planning and decision-making.
40
-------
Protecting other at-risk groups
Protecting members of other at-risk groups,
including older adults, people with heart or lung
disease, pregnant women, and people of lower SES,
is also a high priority for public health officials.
Maintaining good indoor air quality, using the
information provided above, is especially important
in locations where these people are located, such as
gyms, senior centers, hospitals, or residential facilities
for older adults. To protect some at-risk groups,
such as people of lower SES who may live in homes
without air conditioning or in locations where the
use of air conditioning may not be common, it is
advisable to consider setting up cleaner air shelters.
In addition, it is important to recognize that people
of lower SES may experience social vulnerability
due to socioeconomic and demographic factors (e.g.,
socioeconomic status, household composition and
disability, minority status and language, and housing
and transportation) that affect the resilience of
communities (Flanagan et al., 2011). In disasters such
as wildfires, the socially vulnerable are more likely to
be adversely affected and less likely to recover.
In general, individuals in these groups should be
advised to avoid or limit outdoor activities once air
quality is characterized as "Unhealthy for Sensitive
Groups" (orange on the AQI) and to remain indoors
with windows closed if air quality is categorized as
"Very Unhealthy" (purple on the AQI). Families
should consider using an air cleaner with a HEPA
filter that will help to reduce indoor air pollution, as
well as to avoid adding particles by smoking tobacco,
using wood-burning stoves or fireplaces, and candles,
and only using a vacuum with a HEPA filter.
Protecting outdoor workers
Many workers have jobs that require them to work
outdoors. Occasionally these workers may be exposed
to wildfire smoke and other hazards due to wildfires.
In addition to the workers who are directly involved
with wildland fire management and suppression,
there are also workers engaged in supporting fire
response (e.g., at base camp or evacuation centers)
or cleanup efforts (e.g., demolition crews) , and
many others who continue to do their usual non-
fire related outdoor jobs (e.g., agricultural workers,
landscapers, park personnel) during an incident.
Similar to the general public, outdoor workers may
be at risk for adverse health impacts from smoke
or ash exposure, particularly if they are in an at-risk
group (described elsewhere in this Guide). However,
some recommendations made to the public on how
to reduce their exposures to wildfire hazards may not
be relevant for outdoor workers who must continue
to work. In addition, their employers may not have
anticipated these hazards and may be ill equipped to
implement effective protections. To better address
these issues, employers and employees should
prepare for and plan to implement procedures to
protect outdoor workers.
The Occupational Safety and Health Administration
(OSHA) is the regulatory entity for employee health
and safety but, in about half of the states, a federal
OSHA-approved state OSHA program regulates
non-federal workplaces. There are currently no
occupational standards specifically for wildfire
smoke, except in California. On July 18, 2019,
the California Safety and Health Standards Board
adopted an emergency regulation for a Cat/ OSHA
standard to protect workers from hazards associated
with wildfire smoke. This standard, Title 8 California
Code of Regulations Section 5141.1, effective on July
29, 2019 and will be followed by a process to develop
a permanent regulation dittos: / /www.dir.ca.p~ov /
dosh/ doshreg/Protectioti-from-Wildfire-Smoke.
Although healthy adult workers may not be
significantly affected by short-term exposure to
smoke or ash while working outdoors, the risk
of adverse health effects is dependent on the
contaminant levels, type(s) of material burned,
duration of exposure, level of physical activity, age
of the worker, individual susceptibility (e.g., pre-
existing heart or lung disease), as well as other factors
(see Chapter 1). As a result, responses to exposures
will vary.
Employers can take steps to protect healthy as well
as more at-risk workers from the negative health
impacts of unhealthy air quality. Some of the same
recommendations listed in this document for the
general public can apply when working outdoors
41
-------
in a smoky environment. Options for limiting
workers' smoke exposure include postponing or
shortening time spent outdoors; focusing on only
performing high priority tasks; relocating workers or
rescheduling work tasks to smoke-free or less smoky
areas or times of the day; reducing outdoor workers'
physical activity and exertion levels; encouraging
and ensuring workers take frequent breaks inside
cleaner air spaces such as enclosed structures or
vehicles with recirculating air; and encouraging and
using air cleaners with HEPA (or other protective)
filters in indoor working areas to reduce overall
smoke exposure.
In some cases, the use of particulate respirators
should be considered to protect workers who cannot
implement the exposure reduction recommendations
listed above when performing outdoor work (see
additional information below). Workers involved in
post-fire cleanup activities clearly must be protected
from exposure to ash and all other hazards (see
sections pertaining to after-fire hazards) by using a
range of control methods (e.g., dust suppression,
personal protective equipment).
When other measures are not sufficient to control
a respiratory hazard, OSHA requires employers
to provide respirators that are appropriate for the
hazard and work situation. An OSHA-compliant
respirator program names a qualified person
responsible for administering the program and
describes procedures for respirator selection, medical
evaluation for safe respirator use, fit testing for tight-
fitting respirators, training on topics such as how to
use and maintain respirators, and program evaluation.
Pre-planning and preparing for how to best
implement these recommendations in the workplace
are critical. This is especially true in areas where
wildland fire smoke exposure is common, and
workers are required to perform their work outdoors,
even when the air quality is considered unhealthy,
very unhealthy, or hazardous. Working together,
employers and employees can take steps to reduce
their exposures to the hazards associated with a
wildland fire.
Prolonged smoke events
For smoke events that last for more than a few
days or that occur repeatedly over the course of
fire season, public health officials should consider
all options in communicating the importance of
reducing smoke exposure. Messages should include
actions individuals can take to reduce smoke
exposure and should highlight the benefits of
creating cleaner air spaces in homes. The longer a
smoke event continues, the more people will start
to experience adverse health effects. Therefore,
exposure reduction measures that are recommended
for short-term exposures to smoke become even
more important to take with prolonged exposures.
Prolonged smoke events may require consideration
of additional measures to protect the public,
especially people in at-risk groups.
If they haven't already, public health officials should
consider partnering with external businesses,
agencies, and non-profits to provide spaces with
cleaner air for the public to go during the day if
it becomes necessary. These cleaner air spaces
could include schools, senior centers, libraries, and
shopping malls. Making spaces with cleaner air
available during the day can provide an alternative for
people unable to reduce smoke levels in their homes,
or unwilling or unable to evacuate to a designated
cleaner air shelter or out of the area to reduce their
smoke exposure. Before advertising or advocating for
these cleaner air spaces, public health officials should
confirm that the locations have adequate filtration for
particles. This clean air protection may be provided
by a MERV 13 or higher filter in the HVAC system
or a properly sized portable air cleaner with HEPA
filtration. Building managers should continue to
ensure that the building is adequately ventilated and
that fresh air intakes have high-efficiency (MERV
13 or higher) filters to clean the air entering the
building. Altering the building pressure balance by
reducing or stopping air intake could actually create
indoor air quality issues that could offset any benefit
of reduced smoke exposure. For more information,
refer to Appendix D. Cleaner air spaces should also
42
-------
have institutional controls to limit smoke infiltration,
such as limited door and window use. .Appendix 13
provides some guidelines for creating cleaner air in
large spaces.
As smoke events continue, stress associated with
increasing health concerns, loss of control over daily
activities, reduction in physical activity, and isolation
resulting from remaining at home indoors can cause
mental health issues to arise. During a prolonged
smoke event or repeated smoke events, make cleaner
air spaces available where people can socialize. One
beneficial strategy that has been reported consists
of waiving fees for gym use, which allows people
to get exercise and interact with others. Be aware of
mental health issues in your jurisdiction and consider
creating messages about mental health and available
mental health services.
Protecting pets and livestock
Many people ask how wildfire smoke affects pets and
livestock. As with humans, high levels of smoke may
irritate animals' eyes and respiratory tract. Animals
with heart or lung disease are especially at-risk and
should be closely watched during periods of poor
air quality. Strategies to reduce animals' exposure to
smoke are like those for humans: reduce the time
spent in smoky areas; if animals are indoors, keep
indoor air clean; provide animals with plenty of
water; limit physical activities that will increase the
amount of smoke breathed into their lungs; and
reduce exposure to dust or other air pollutants. If
pets or livestock are coughing or having difficulty
breathing, the owner should contact a veterinarian.
Two factsheets, Protect Your Pets from Wildfire
Smoke and Protect Your Large Animals and
Livestock from Wildfire Smoke, are available for
dissemination to the public.
Consider where pets and livestock could be housed
if the evacuation of people from areas within your
jurisdiction becomes necessary. For example, in some
places, local shelters will house pets in carriers and
it is not uncommon for temporary livestock shelters
to be created in local fairgrounds or parking lots.
Animals that are older or have a medical condition
that increases sensitivity to smoke, may require
sheltering facilities that can provide cleaner air or
adequate medical attention. Animal accommodations
are frequently set up with participation from local
animal control, humane society or other animal
rescue groups. For more information, check
the American Veterinary Medical Association
(AYMA) website: httns: / /www.a.vma..orp7public/
EmeryencvCare / Paiys /Pets-and-Disasters.aspx.
Air quality cautionary statements and
recommended public actions
Table S shows actions for public health officials
to consider at the different AQI categories. Public
health officials may want to recommend some or
all of the recommended actions associated with
these categories, based on an assessment of the
local situation. Some factors that also should be
considered include:
Predicted fluctuations in PM2 5 levels. Are the
peaks of PM25 predicted to occur relatively infre-
quently, interspersed with longer periods of good
air quality, or to occur multiple times per day,
superimposed on higher-than-usual PM25 levels?
Predicted duration of high PM25 levels. For
instance, if air quality is predicted to be in the
"Unhealthy for Sensitive Groups" range or worse
for multiple days to weeks, public health officials
might consider opening cleaner air shelters or
recommending evacuation plans for at-risk popu-
lations, including individuals with chronic lung or
heart disease, who cannot take adequate personal
protective actions to reduce exposures.
Potential indirect effects. High PM25 levels can
impair visibility and increase the risk of traffic
accidents. This may be reason enough to cancel
an evening indoor event at a local high school, for
example.
43
-------
Table 4. Health effects and cautionary messages for at risk populations for each
AQI category
AQI
Category
(AQI Values)
Health
Effects
Cautionary Statements
Other Protection Messages
Good
(0-50)
None expected
None
None
Moderate
(51-100)
Possible
aggravation of
heart or lung
disease
Unusually sensitive individuals should
consider limiting prolonged or heavy
exertion.
People with heart or lung disease should
pay attention to symptoms.
Individuals with symptoms of lung
or heart disease, including repeated
coughing, shortness of breath or
difficulty breathing, wheezing, chest
tightness or pain, palpitations, nausea,
unusual fatigue or lightheadedness,
should contact a health care provider.
If symptomatic, reduce exposure to particles by following
advice in box below.
Unhealthy for
Sensitive Groups
(101-150)
Increasing
likelihood of
respiratory or
cardiac symptoms
in sensitive
individuals,
aggravation
of heart or
lung disease,
and premature
mortality in people
with heart or lung
disease and older
adults
Sensitive Groups: People with heart or
lung disease, the elderly, children, and
pregnant women should limit prolonged
or heavy exertion.
Limit time spent outdoors.
Avoid physical exertion.
People with asthma should follow their
asthma management plan.
Individuals with symptoms of lung or
heart disease that may be related to
excess smoke exposure, including repeated
coughing, shortness of breath or difficulty
breathing, wheezing, chest tightness or
pain, heart palpitations, nausea, unusual
fatigue or lightheadedness, should contact
a health care provider.
Keep doors and windows closed, seal large gaps as much
as possible.
Avoid using exhaust fans (e.g., kitchen, bathroom, clothes
dryer, and utility room exhaust fans).
Keep the garage-to-home door closed.
If cooling is needed, turn air conditioning to re- circulate
mode in home and car, or use ceiling fans or portable
fans (but do not use whole house fans that suck outdoor
air into the home).
If a home has a central heating and/or air conditioning
system, install higher-efficiency filters (e.g., filters rated at
MERV 13 or higher) if they can be accommodated by the
system. Regardless of whether a filter upgrade has been
performed, the system's circulating fan can be temporarily
set to operate continuously to obtain maximum particle
removal by the central air system's filter, although this
will increase energy use and costs.
Operate appropriately sized portable air cleaners to
reduce indoor particle levels.
Avoid indoor sources of pollutants, including tobacco
smoke, heating with wood stoves and kerosene heaters,
frying or broiling foods, burning candles or incense,
vacuuming, and using paints, solvents, cleaning products,
and adhesives.
Keep at least a 5-day supply of medication available.
Have a supply of non-perishable groceries that do not
require ranking.
44
-------
Table 4. Health effects and cautionary messages for at risk populations for each
AQI category, (continued)
AQI
Category
(AQI Values)
Health
Effects
Cautionary Statements
Other Protection Messages
Unhealthy
(151-200)
Increased
aggravation
of heart or
lung disease
and premature
mortality in
persons with
heart or lung
disease and older
adults; increased
respiratory
effects in general
population.
Sensitive Groups: Should avoid prolonged
or heavy exertion
Everyone; Should limit prolonged or
heavy exertion
Limit time spent outdoors.
Individuals with symptoms of lung
or heart disease that may be related
to excess smoke exposure, including
repeated coughing, shortness of breath
or difficulty breathing, wheezing, chest
tightness or pain, palpitations, nausea
or unusual fatigue or lightheadedness,
should contact your health care provider.
Sensitive Groups: Stay in a "clean room" at home (where
there are no indoor smoke or particle sources, and use a
non-ozone producing air cleaner).
Go to a "cleaner air" shelter (see Appendix D) or
possibly out of area
Everyone: Follow advice for sensitive groups in box above.
Identify potential "cleaner air" shelters in the community
(see Appendix D).
Very Unhealthy
(201-300)
Significant
aggravation of
heart or lung
disease, premature
mortality in
persons with
heart or
lung disease
and older adults;
significant
increase in
respiratory effects
in general
population.
Everyone: Should avoid prolonged
or heavy exertion and stay indoors,
preferably in a space with filtered air.
Everyone: If symptomatic, seek medical attention. If you
are unable to create your own cleaner indoor air space
to shelter in place, evacuate to a cleaner air shelter or
leave the area, if it is safe to do so.
Hazardous
(> 300)
Serious
aggravation of
heart or lung
disease, premature
mortality in
persons with
heart or lung
disease and older
adults; serious
risk of respiratory
effects in general
population.
Everyone: Should avoid any outdoor
activity, and stay indoors, preferably in a
space with filtered air.
Everyone: If symptomatic, seek medical attention. If you
are unable to create your own cleaner indoor air space
to shelter in place, evacuate to a cleaner air shelter or
leave the area, if it is safe to do so.
'Higher advisory levels automatically incorporate all of the guidance offered at lower levels.
45
-------
Table 5. Recommended actions for consideration by public health officials
AQI Category
(AQI Values)
PM2s'
Mg/m3
24-hr avg
Recommended Actions for Consideration
Good
(0-50)
0-12
If smoke event forecast, implement communication plan.
Moderate
(51-100)
12.1-35.4
Prepare for full implementation of School Activity Guidelines (https://www3.epa.gov/airnow/
flagAchool-chart-20l4.pdf).
Issue public service announcements (PSAs) advising public about health effects, symptoms,
and ways to reduce exposure.
Distribute information about exposure avoidance.
Unhealthy for Sensitive Groups
(101-150)
35.5-55.4
Evaluate implementation of School Activity Guidelines
If smoke event projected to be prolonged, evaluate and notify about possible sites for
cleaner air shelters.
If smoke event projected to be prolonged, prepare evacuation plans for at-risk populations.
Unhealthy
(151-200)
55.5-150.4
Full implementation of School Activity Guidelines
Consider canceling outdoor events (e.g., concerts and competitive sports), based on public
health and travel considerations.
Very Unhealthy
(201-300)
150.5-250.4
Move all school activities indoors or reschedule them to another day. Cancel school
physical activities (e.g., physical education, athletic practice) unless the school is able to
provide cleaner indoor air for the students.
Consider closing some or all schools
Cancel outdoor events involving activity (e.g., competitive sports).
Consider canceling outdoor events that do not involve activity (e.g. concerts).
Hazardous
(> 300)
250.5>500
Consider closing schools2.
Cancel outdoor events (e.g., concerts and competitive sports).
Consider air quality in indoor workplaces and take measures to protect workers as
needed3
Consider curtailment of outdoor work activities unless the workers have a fully
implemented respirator plan in place and clean air respite breaks.
If PM levels are projected to remain high for a prolonged time, consider evacuation of
at-risk populations.
1 If only PM|0 measurements are available during smoky conditions, assume that the PM|0 is composed primarily of fine particles (PM25), and that therefore the AQI and
associated cautionary statements and advisories for PM25 may be used.
2 See school considerations in section on Protecting Children, above. Newer schools with a central air cleaning filter may be more protective than older, leakier schools. Also,
being at school may mean children's activity levels can be better monitored. It is important to make schools a safe place for children.
3 See Appendix C for guidance.
46
-------
Public service announcements
This section discusses using public service
announcements (PSAs) to deliver messages to the
public in advance of wildfire season. Preparing for
wildfire season includes planning what actions can
be taken by individuals well in advance of a wildfire
smoke event. In areas where fires are likely to occur,
state and local public health agencies should consider
running pre-season PSAs or news and social media
announcements to advise the public on preparing
for the fire season. The factsheet, Prepare for Fire
Season, is available on the AirNow website. EPAs
webpage Wildfires and indoor. dity also
provides general information on how to reduce
exposure to wildfire smoke in residences. PSAs
should be simple (e.g., "the season for wildfires is
approaching; take action now to protect your health
and prepare your home") and should list a contact
phone number and website for further information.
PSAs are also useful during fire or smoke events
to provide timely updates on the situation, along
with advice on protective actions. Effective PSAs
use simple, non-technical messages that people
can remember, such as "stay indoors" or "limit
outdoor activities." News and social media releases
and website posts should be used to provide more
detailed information, including information for the
general public and for people with chronic diseases.
When wildfire risk is high, the area federal, state,
tribal, or local land manager is also likely initiating
a public information campaign to prevent wildfires,
providing a natural partner for messaging about
smoke with these agencies.
Consider reaching out to weather forecasters and
news reporters, who are a valuable resource for
sharing information with the public. Their role
as communicators on television, radio, print, and
online outlets makes them an essential partner
in any outreach strategy. When reaching out to
news reporters and meteorologists to "pitch" your
messages:
Tell them who you are, what agency you repre-
sent, and that your campaign affects the health
and safety of the community.
Make sure they have your contact information, in-
cluding e-mail address, and at least one telephone
number.
General recommendations to the public
General recommendations to the public should
include at least the following:
1. Prepare for wildfire season. Have a several-day
supply of nonperishable groceries that do not re-
quire cooking, since cooking (especially frying and
broiling) can add to indoor pollutant levels. Have
extra medications, such as asthma medicine. For
more information for the public about steps to be
ready use the Prepare for Fire Season factsheet.
2. If you develop symptoms suggesting lung or
heart problems, consult a health care provider as
soon as possible.
3. Be alert to local announcements, air quality fore-
casts, and changing smoke conditions.
4. Be aware that outdoor events, such as athletic
games or competitions, may be postponed or
canceled if smoke levels become elevated.
5. During a wildfire smoke event, you can take
steps to limit smoke infiltration and clean the air
indoors with either the right-sized portable air
cleaner with true HEPA filtration or a HVAC
filter with a MERV rating 13+. See the EPA web-
page Wildfires and Indoor .Air Quality.
47
-------
Recommendations for people with chronic
diseases
Recommendations for people with chronic diseases
should include at least the following:
1. These recommendations are for people with
chronic diseases, including heart or lung disease.
Have an adequate supply of medication (more
than 5 days).
2. People with asthma should have a written asthma
action plan. Check the EPA website for resources
on asthma action plans: httos: / /www.epa..p;ov /
asthma/asthma-action-nlan
i. People with heart or lung disease should check
with their health care providers about precau-
tions to take during smoke events. They should
do this prior to the fire season if they live in an
area that has the potential for wildfires.
ii. Contact a health care provider if your condi-
tion worsens when you are exposed to smoke.
iii.When using one or more portable air cleaners,
buy air cleaners that are appropriately sized for
the intended rooms, as specified by the manu-
facturer, before a smoke emergency occurs. Be
sure they are certified by California as low-or-
no ozone models by checking the California Air
Resources Board website at https: / /www.arb.
ca.gov / research / indoor/ aircieaners / certified,
htm.
iv. A news release could also include recommen-
dations for preparing residences to keep smoke
levels lower indoors, and on the appropriate
use of respiratory protection, as discussed
above. See factsheets on indoor Air nitration
and Protect Your Lungs from Wildfire Smoke
or .Ash, the webpage Wildfires and indoor .Air
Quality, and Appendices B and D.
Use social media to raise awareness
Social media outlets, such as Twitter, Facebook, and
Instagram, are a good way to raise awareness about
wildfire smoke health protection. Keep in mind that
you have many different audiences, so you will need
to use many different media to share messages about
smoky conditions in your community.
For information on how to use social media for
health messages, visit the Centers for Disease Control
and Prevention Health Communicator's Social Media
Toolkit: https://www.cdc.gov/ socialmedia/tools/
guidelines/socialmediatoolkit.html.
Social media can attract and direct the public to
a central website or document for distribution.
This central website will provide complete wildfire
smoke information. For social media success, post
simple messages that reflect the community's needs
at the time. Post different messages but always
copy and paste the same link to direct the public to
your webpage with the most complete, up-to-date
information. Repeating the link to a central website
is a good way to reach out and make more people
aware of the information.
Prior to wildfire smoke season, create a template
with a simple graphic element that is repeated on the
central webpage and use the same look for any other
wildfire smoke announcements, such as paper flyers,
email, and social media, so that when the public sees
it they will immediately recognize the information.
Make the template usable in both electronic and print
media. This can be something as simple as the health
department or local government logo and a heading
such as WILDFIRE SMOKE ALERT.
Social media messages, like any messages, require
advance planning. You will want to find the right
contact in your office or agency who oversees social
media, ask them about the process for approving and
posting messages, propose messages they can send
out in a timely fashion, and evaluate the effectiveness
of messages delivered over social media.
In the off-season, you can share messages from
other sites by retweeting or sharing the information
48
-------
previously posted on a reputable social media site
such as the CDC or EPA. Messages can include
topics such as brush cleanup around the perimeter of
a home. You can look to the following resources to
find messages to share:
h tt p s: / / twi tte r. c o m /. A..I. R.N ow
https://www.tacebook.com/airnow
h ttps: / / twi tte r. co m / CD Cg tiyi ro ti me ti t
https:/ / twitter.com/CDCemerrency
Preparedness
Preparation is key to effective response to wildfire
smoke events. In the months leading up to fire
season, the National Significant Wildland Fire
Potential Outlooks (https: / /www.predictiveservices.
tiirc.P'Ov /outlooks /outlooks.htm). developed by
the National Interagency Fire Center (NIFC), can
give an idea of the predicted severity of the coming
months of the fire season. These assessments
indicate which areas of the country are likely to see
various levels of fire activity and are designed to
inform decision makers for proactive wildland fire
management. Outlooks are available for the current
month, the month following and a seasonal look at
the two months beyond that. However, long-range
predictions can be uncertain. Also, even if the NIFC
is predicting normal or below normal fire activity in
your region, you may be downwind of an area that is
likely to see heightened activity.
Before wildfire season arrives, public health officials
should consider taking some or all of the following
steps, especially if they are in an area predicted to
be a higher risk of fire. This is a simple list, more
detailed information about each of these steps can be
found other places in the Guide.
Recommended steps for public health officials
before fire season
Recommended steps for public health officials in
areas likely to experience smoke to take before fires
start include:
1. Check fire risk level in monthly outlooks at Na-
tional Interagency Fire ("enter (NIFC) website
and, especially if high, communicate risk to the
public.
2. Consider how to implement the recommended
actions in '.Table 5 above.
o Identify locations that could serve as cleaner
air shelters.
o Identify locations that could serve as cleaner
air spaces.
o Check indoor air quality (IAQ) capabilities in
places where at-risk populations congregate
(e.g., schools, preschools and daycares; senior
centers and nursing homes) and investigate
approaches to improving IAQ, if necessary.
o Have supply of NIOSH-approved respirators
to disseminate to public; consider approaches
to supplying portable air cleaners.
3. Prepare a communication plan.
o Include approaches for quick dissemination of
information to the public (e.g., social media).
o Include approaches to reach members of at-
risk populations.
o Develop messages about mental health and
available mental health services, since stress
can cause mental health issues to arise.
o Inform public about steps to be ready - use
Prepare for Fire Season factsheet.
4. Form partnerships with important partners or
stakeholders, for example: air quality agencies,
local health providers, the media and others.
o Help local health providers learn about the
health effects of smoke and the populations at
greatest risk using the EPA and CDC continu-
ing education course about particulate matter,
Particle Pollution and Your Patients' Health.
49
-------
After the fire, the effectiveness of the response
to a wildfire smoke event should be assessed so
needed improvements can be identified. A season-
ending discussion with partners and preparation
of a "lessons learned" plan or report will help the
partnership continue to grow and improve.
Build strong partnerships
Wildfires can start and spread rapidly, and a smoke
event may descend on a community in a matter
of hours. Ideally, relationships between health
departments, air quality agencies, land management
agencies, and other partners will be in place before
a crisis begins. To reduce potential public confusion,
partner agencies responding to a wildfire smoke
episode need to begin working together right away
to inform the public of smoke and health risks using
consistent messages. A pre-existing partnership
enables a rapid response to a serious smoke episode
and allows everyone to quickly access and share vital
information.
All agencies working on fire and smoke response
should coordinate closely during the incident to
ensure consistent communications and to leverage
resources for developing and delivering information
to the public. This can be achieved through steps
such as cross-linking websites, and clearly directing
public and media inquiries to the appropriate agency
and subject matter experts. Some agencies may have
the best experts for media interviews while another
may have easy access to language translation services.
One partner may be able to access communication
material design experts while another contributes
monitoring data analysis experts. Building a team
that capitalizes on agency and individual strengths
while breaking down agency boundaries is the most
effective way to quickly serve the public in an air
quality emergency.
Physicians and other health care providers often
have a high degree of credibility with the public.
Having a good working relationship with local
health providers who are knowledgeable about the
health effects of smoke can be very useful in getting
health and exposure reduction information out to
the public through the media. EPA has developed
an on-line training course, Particle Pollution and
Your Patients' Health (https://www.epa.gov/
pmcourse). to educate health providers about the
effects of particulate matter. The training includes
a section on high-particulate matter events, such
as wildfires, that is consistent with the information
and recommendations in this guide. Physicians,
nurses, and health educators can receive continuing
education credits from CDC for taking this online
training.
Remember that while working with local media and
posting information online is important, it is not the
only way to deliver information during an emergency.
Other methods are effective such as posters, door
hangers, fliers, or radio and television. Note that
smoke and messaging needs frequently cross state
and international boundaries so coordination needs
to be developed beyond typical jurisdictions.
Putting together a wildfire smoke team
Responding to the needs of the public in case of a
serious or prolonged wildfire smoke event will be
far more effective if relevant state, local, and federal
agencies and organizations are engaged and working
together as a team. Some states have ad hoc wildfire
smoke response teams that have already formed
during wildfire smoke response efforts, other states
or areas may need to start at the beginning to find
and engage partners. Some states have prepared
formal emergency smoke response plans that outline
local points of contact, responsibilities of state
agencies and other cooperators, and instructions for
acquiring extra needed resources such as monitors or
masks. In some states when wildfire smoke impacts
are serious or prolonged, these agencies and other
local cooperators hold daily or as-needed conference
calls to share information and coordinate air quality
messaging and public outreach efforts. Participating
in these internal calls can be very valuable for public
health agencies. Possible key partners in a public
response effort include:
State and local clean air agencies - State and
local clean air agencies are expert at accessing and
summarizing local air monitoring data and often
have the ability to forecast upcoming
50
-------
meteorology and dispersion conditions that will
affect smoke movement and accumulation. State
air agencies often work with the National Weath-
er Service to have air pollution advisories issued
when needed.
Federal and state land management agen-
cies Typically, federal or state land management
agencies have the lead in wildfire suppression and
response. Any ARAs working in the area are likely
assigned either to a wildfire incident management
team or to a Federal Agency Administrator. ARAs
are a very valuable source of information for the
public health community and can help spread
public health messages through ongoing com-
munications. ARA efforts are improved through
consultation and coordination with state public
health entities. To see if an ARA is working in an
area check wwwwtldlatidfiresmoke.net.
Incident management teams assigned to large
wildfires are expert at connecting with local
communities and frequently host public meetings
where smoke and appropriate public responses
may be discussed. These meetings can be an ex-
cellent forum for ARAs and public health agen-
cies to deliver messages about smoke and public
health.
Tribes Many tribal communities run their own
air quality programs and have local information
about supplemental monitors and effective out-
reach to their communities. EPA regional offices
assist with tribal air programs. Federal agencies
can help provide information to tribes if a fire is
on, or smoke is affecting, lands in Indian coun-
try. Federal agencies have a trust responsibility to
tribes and have established contacts who can help
deliver information on wildfire smoke and health.
State and local public health agencies - State
and local health agencies are expert at communi-
cating health risks and protective actions in sim-
ple language the public can understand and are
well linked to organizations,such as assisted living
facilities, hospitals, and clinics, that serve at-risk
groups. Public outreach needs of public health
agencies often mean they have language transla-
tion expertise so important health messages can
reach non-English speakers.
EPA regional offices and the Wildland Fire Air
Quality Response Program may have por table
air quality monitors that can be deployed to
smoky areas that are not well represented by
existing state networks. The Wildland Fire Air
Quality Response Program website (www.wtld-
land fires moke, net) also provides tools to help
summarize monitoring data from state moni-
toring networks and from emergency monitors
deployed to wildfires.
School systems - School administrators are
frequently anxious for advice on how to best
protect their students from smoke. Schools can be
invaluable channels for accessing not only
children but entire families, particularly in regions
where children may be more literate in English
than older family members. In addition, schools
can sometimes serve as temporary shelters for
evacuees.
Faith-based and community-based organi-
zations Faith-based and community-based
organizations can help disseminate awareness
messages and can potentially serve as partners for
sheltering evacuated residents.
Cleaning up after the fire
Even after the worst of the fire and smoke is
over there remain health and safety hazards that
homeowners should be aware of. Exposure to
lingering smoke and ash from a wildfire can cause
significant health effects in both healthy individuals
and those in at-risk groups. People may experience
symptoms including respiratory irritation, heat-
related illness, and even emotional stress after a fire.
Physical stress from cleanup activities, exposure to
toxic chemicals, damaged power lines, and equipment
such as portable generators can cause injuries during
clean up. To learn more about the health and safety
hazards that people might encounter after a wildfire,
refer to .Appendix K.
51
-------
Even after the fire is out, smoke and ash residue can
affect the air quality in affected structures. Depending
on the severity of smoke intrusion into the building
and the length of exposure, some people may notice
a lingering odor when they return to their homes,
schools, or places of work. Removal of smoke odor
is difficult, but there are ways to diminish the odor,
including beginning with a thorough airing of any
structure. If conditions permit, windows and doors
can be opened and fans can be placed in rooms to
circulate the air. If it is too warm or cold to open the
doors and windows, a large portable air cleaner that
has a high-efficiency filter (HEPA) can be used to
ventilate the rooms and promote air exchange to help
remove the odors. Any air cleaner used should meet
ozone emissions and electrical safety requirements.
Approved air cleaners can be found here: httns:/ /
www.arh.ca.pov / research / indoor/ airdeaners /
certified.htm. Note that while HEPA filters will
remove lingering fine particles in the air, they do
not remove the gaseous chemicals that cause odors
associated with wildfire smoke. These chemicals must
be removed by using a portable air cleaner with an
activated charcoal prefilter or a prefilter composed
of alumina coated with potassium permanganate and
replacing the prefilter frequently. Most prefilters on
smaller portable air cleaners will saturate quickly and
lose effectiveness in a smoky environment. Portable
air cleaners with more robust odor removal are
available but are frequently on the higher end of the
price spectrum.
In addition to ventilation, it is also important to
thoroughly clean the affected space. Every surface
of the space that was exposed to smoke will need
to be cleaned. If ash or other hazards are present,
individuals performing cleanup work should wear
protective clothing and equipment, such as a well-
fitting N-95 respirator, leather gloves, safety glasses
or goggles, long pants, a long-sleeved shirt, and
shoes with rugged soles. Cleaning will include wiping
down the walls, floors, windows, baseboards, doors,
frames, cabinets, furniture, and other surfaces with
a dilute solution of water and soap. Some people
may choose to use additional cleaning products;
however, it is important to note that some cleaners
also impact indoor air quality. Those who choose to
use additional cleaning products should be advised
to read label instructions carefully and follow
all instructions. Curtains, rugs, furniture covers,
bedding, and anything that can be safely washed in
a washing machine can be cleaned in this manner.
Carpets will also need to be cleaned. This can be
done professionally or by using a carpet cleaner
rented from a local market or rental center. Often
the building ductwork for the heating and cooling
system will not be an issue because in many cases
the power goes out during fire events and the AC
systems do not circulate smoke- and ash-filled air
through the ductwork for very long. In cases where
ductwork does have smoke residue and is a source
of odors, it is recommended to consult with a local
smoke remediation company or HVAC contractor to
see what options are available to clean it. EPA has a
guide for consumers on duct cleaning: httns://www.
epa.gov / indoor-air-auality-iaq/ should-vou-have-air-
ducts-your-home-deaned.
The use of an ozone generator to remediate smoke
odor is not recommended because ozone can create
as many problems as it is intended to fix. Many
of the chemicals that are broken up by ozone can
produce byproducts that are also dangerous to health.
Furthermore, ozone does not remove ash and other
particles from the air and indoor surfaces. If an
ozone generator is used to remove smoke odors it
should be used only by a remediation professional.
The space where the ozone generator is being used
must be unoccupied during, and for a designated
period after, its use to be sure that no one is exposed
to the ozone. Finally, some companies claim to use
"hydroxyl" generators for remediation. Hydroxyl
radicals are highly reactive and can also create
chemical byproducts. These devices should be used
with the same caution as ozone generators.
52
-------
REFERENCES
Adetona O, Reinhardt TE, Domitrovich J, Broyles G, Adetona AM, Kleinman MT, Ottmar RD, Naeher LP.
Review of the health effects of wildland fire smoke on wildland firefighters and the public. Inhal Toxicol
2016;28(3):95-139. doi: 10.3109/08958378.2016.1145771.
Allen R"V^ Adar SD, Avol E, Cohen M, Curl CL, Larson T, Liu LJ, Sheppard L, Kaufman JD. Modeling the res-
idential infiltration of outdoor PM(2.5) in the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA
Air). Environ Health Perspect 2012;120(6):824-830. doi: 10.1289/ehp.l 104447.
Amegah AK, Quansah R, Jaakkola JJ. Household air pollution from solid fuel use and risk of adverse pregnan-
cy outcomes: a systematic review and meta-analysis of the empirical evidence. PLoS One 2014;9(12):ell3920.
doi: 10.1371/journal.pone.0113920.
Brim SN, Rudd RA, Funk RH, Callahan DB. Asthma prevalence among US children in underrepresent-
ed minority populations: American Indian/Alaska Native, Chinese, Filipino, and Asian Indian. Pediatrics
2008;122(l):e217-222. doi: 10.1542/peds.2007-3825.
California Air Resources Board. (2014) Air Cleaning Devices for the Home. Retrieved April 23, 2019 from-
http: / /www.a.rb.ca..P'Ov / research / indoor/acdsumm.pdf.
California Air Resources Board. (2019) Air Cleaner Information for Consumers. Retrieved April 23, 2019 from
http://www.arb.ca.gov/ research/ttidoor/aircleatiers/ consumers, htm.
Centers for Disease Control and Prevention. (2017) "Asthma." Retrieved April 19, 2019 from https:/ /www.
cdc.gov / tichs / fas tats /as thma. htm.
Centers for Disease Control and Prevention. (2018) "Basics About COPD." Retrieved April 4, 2019 from
https: / / www.cdc.pov / cond /hasics-ahouthtml.
Chen C, Zhao B. Review of relationship between indoor and outdoor particles: I/O ratio, infiltration factor
and pene. Atmospheric Environment 2011;45(2):275-288.
Daniels RD, Kubale TL, Yiin JH, Dahm MM, Hales TR, Baris D, Zahm SH, Beaumont JJ, Waters KM, Pinker-
ton LE. Mortality and cancer incidence in a pooled cohort of US firefighters from San Francisco, Chicago and
Philadelphia (1950-2009). Occup Environ Med 2014;71(6):388-397. doi: 10.1136/oemed-2013-101662.
DeFlorio-Barker S, Crooks J, Reyes J, Rappold AG. Cardiopulmonary effects of fine particulate matter expo-
sure among older adults, during wildfire and non-wildfire periods, in the United States 2008-2010. Environ
Health Perspect 2019;127(3):37006. doi: 10.1289/ehp3860.
Fisk WJ. Health benefits of particle filtration. Indoor Air 2013;23(5):357-368. doi: 10.1111/ina.l2036.
Fisk WJ, Chan WR. Health benefits and costs of filtration interventions that reduce indoor exposure to PM25
during wildfires. Indoor Air 2017;27(l):191-204. doi: 10.1111/ina.12285.
Flanagan BE, Gregory EW, Hallisey EJ, Heitgerd JL, Lewis B. A social vulnerability index for disaster manage-
ment. J Homel Secur Emerg Manag 2011; 8(1): Article 3.
Fruin SA, Hudda N, Sioutas C, Delfino RJ. Predictive model for vehicle air exchange rates based on a large,
representative sample. Environ Sci Technol 2011;45(8):3569-3575. doi: 10.1021/esl03897u.
53
-------
GroB, S., Esselborn, M., Weinzierl, B., Wirth, M., Fix, A., and Petzold, A. Aerosol classification by airborne
high spectral resolution lidar observations. Atmos. Chem. Phys 2013; 13, 24872505. doi:10.5194/acp-13-
2487-2013.
Hansen ES. A cohort study on the mortality of firefighters. Br J Ind Med 1990;47(12):805-809.
Holstius DM, Reid CE, Jesdale BM, Morello-Frosch R. Birth weight following pregnancy during the 2003
Southern California wildfires. Environ Health Perspect 2012; 120(9):1340-1345. doi: 10.1289/ehp.ll04515.
Howard-Reed C, Wallace LA, Ott WR. The effect of opening windows on air change rates in two homes. J Air
Waste Manag Assoc 2002;52(2):147-159.
Hudda N, Fruin SA. Carbon dioxide accumulation inside vehicles: The effect of ventilation and driving condi-
tions. Sci Total Environ 2018;610-611:1448-1456. doi: 10.1016/j.scitotenv.2017.08.105.
Hutchinson JA, Vargo J, Milet M, French NHF, Billmire M, Johnson J, Hoshiko S. The San Diego 2007 wild-
fires and Medi-Cal emergency department presentations, inpatient hospitalizations, and outpatient visits: An
observational study of smoke exposure periods and a bidirectional case-crossover analysis. PLoS Med 2018;
15(7):el002601. doi: 10.1371/journal.pmed.l002601.
Kim YH, Warren SH, Krantz QT, King C, Jaskot R, Preston WT, George BJ, Hays MD, Landis MS, Hi-
guchi M, DeMarini DM, Gilmour MI. Mutagenicity and lung toxicity of smoldering vs. flaming emissions
from various biomass fuels: Implications for health effects from wildland fires. Environ Health Perspect
2018;126(1):017011. doi: 10.1289/ehp2200.
Kumagai Y, Caroll M, Cohn P. Coping with interface wildfire as a human event: lessions from the disaster/haz-
ards literature. J Forestry 2004;102(6):28-32. doi:
Lee ES, Zhu Y. Application of a high-efficiency cabin air filter for simultaneous mitigation of ultrafine parti-
cle and carbon dioxide exposures inside passenger vehicles. Environ Sci Technol 2014;48(4):2328-2335. doi:
10.1021/es404952q.
Liu JC, Pereira G, Uhl SA, Bravo MA, Bell ML. A systematic review of the physical health impacts
from non-occupational exposure to wildfire smoke. Environ Res 2015;136:120-132. doi: 10.1016/j.en-
vres.2014.10.015.
Malm WC, Schichtel BA. (2013) Uncertainty associated with estimating a short-term (1-3 hr) particulate matter
concentration from a human-sighted visual range. JFSP Research Project Reports. Project # 13-C-01-01. Retrieved
April 29, 2016 from https:/ / digitalcommotis.util.edu/ifspresea.rch/5.
Naeher LP, Brauer M, Lipsett M, Zelikoff JT, Simpson CD, Koenig JQ, Smith KR. Woodsmoke health effects:
a review. Inhal Toxicol 2007;19(1):67-106. doi: 10.1080/08958370600985875.
National Institute for Occupational Safety and Health [NIOSH]. (2016) Workplace solutions, preparedness
through daily practice; The myths of respiratory protection in healthcare. NIOSH Publication
No. 2016-109. Retrieved May 4, 2016 from httos: / / www.cdc.p~oy / tiiosh / docs / wo-solutions /2016-109 /
pdfs /2016-109.pdf.
Ortman JM, Velkoff V, Hogan H. An aging nation: the older population in the United States. May 2014. In:
Current population reports 2014. US Census Bureau.
Rappold AG, Cascio WE, Kilaru VJ, Stone SL, Neas LM, Devlin RB, Diaz-Sanchez D. Cardio-respiratory
outcomes associated with exposure to wildfire smoke are modified by measures of community health. Environ
Health 2012;11:71. doi: 10.1186/1476-069x-ll-71.
54
-------
Reid CE, Brauer M, Johnston FH, Jerrett M, Balmes JR, Elliott CT. Critical review of health impacts of wild-
fire smoke exposure. Environ Health Perspect 2016;124(9):1334-1343. doi: 10.1289/ehp.l409277.
Reinhardt T, Ottmar R. (2000) Smoke exposure at western wildfires. Research Paper PNW-RP-525. U.S. De-
partment of Agriculture, Forest Service, Pacific Northwest Research Station, Portland, OR. Retrieved April 18,
2019 from http ://wwwlsied.us/pnw/pubs/pnw_rp525.pdf.
Reinhardt TE, Ottmar RD. (2010) Baseline Measurements of Smoke Exposure Among Wildland Firefighters,
Journal of Occupational and Environmental Hygiene, 1:9, 593-606, DOI: 10-1080/15459620490490101.
Sacks JD, Stanek LW, Luben TJ, Johns DO, Buckley BJ, Brown JS, Ross M. Particulate matter-induced health
effects: Who is susceptible? Environ Health Perspect 2011;119(4):446-454. doi: 10.1289/ehp.l002255.
Singer BC, Delp WW, Black DR, Destaillats H, Walker IS. Reducing In-Home Exposure to Air Pollution.
CARB Contract No. 11-311: Final Report httns://ww3.arb.ca.gov/research/apr/nasi if.
Tinling MA, West JJ, Cascio WE, Kilaru V, Rappold AG. Repeating cardiopulmonary health effects in rural
North Carolina population during a second large peat wildfire. Environ Health 2016;15:12. doi: 10.1186/
s12940-016-0093-4.
U.S. Environmental Protection Agency. (2009) Integrated Science Assessment (ISA) for Particulate Matter (Fi-
nal Report, Dec 2009). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-08/139F, 2009.
U.S. Environmental Protection Agency. (2013) Integrated Science Assessment (ISA) of Ozone and Related
Photochemical Oxidants (Final Report, Feb 2013). U.S. Environmental Protection Agency, Washington, DC,
EPA/600/R-10/076F, 2013.
U.S. Environmental Protection Agency. (2015) "Ozone Generators that are Sold as Air Cleaners."
Retrieved April 19, 2019 from httns: / /www.epa.yoy /itidoor-a.ir-aua.lity-ia.a /ozorie-yetierators-are-soid-air-
cieaners.
U.S. Environmental Protection Agency. (2018) Guide to Air Cleaners in the Home (2nd edition). EPA 402-F-
08-004.
USGCRP, 2018: Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment,
Volume II [Reidmiller, DR., C.W Avery, DR. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and
B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 1515 pp. doi: 10.7930/
NCA4.2018.
Vicente A, Alves C, et al. Emission factors and detailed chemical composition of smoke particles from the
2010 wildfire season. Atmospheric Environment 2013; 71:295-303.
Westerling, A.L., A. Gershunov, T.J. Brown, DR. Cayan, M.D Dettinger, 2003: Climate and Wildfire in the
Western United States. Bull. Amer. Meteor. Soc., 84, 595-604, httns://dotorp7l0.1175/6AMS-84-5-595
Wettstein ZS, Hoshiko S, Fahimi J, Harrison RJ, Cascio WE, Rappold AG. Cardiovascular and cerebrovascular
emergency department visits associated with wildfire wmoke exposure in California in 2015. J Am Heart Assoc
2018;7(8). doi: 10.1161/jaha.ll7.007492.
Xu J, Murphy SL, Kochanek KD, Bastian B, Arias E. Deaths: final data for 2016. Natl Vital Stat Rep. 2018;
67(5): 1-75.
55
-------
ADDITIONAL
RESOURCES AND LINKS
Active Wildfire Information
AirNow Fires: Current Conditions, https://airtiow.
gov/ttidex.chii?actioti=topics.smoke wildfires
CAL FIRE, California Department of Forestry and
Fire Protection: http: / /www,fire.ca.gov
Geographic Area Coordination Center, National
Interagency Fire Center: http: / /pacc.nifc.gov/links /
links.htm
InciWeb - Incident Information System: http://
inciweh.tiwcg.gov provides updates on all national
fires, often several times a day.
National Interagency Fire Center Wildland Fire
Morning Report: http://wwwis.fed.us/news/fire
Satellite Images of Fires and Smoke
GeoMAC Wildland Fire Support, Geospatial Multi-
Agency Coordination: httns:/ /p-eomac.usPS.pov
O J ' " """ 1! (r?! ฆ ฆ 1 11 1 ฆ 1 ฆ
NASA Moderate Resolution Imaging
Spectroradiometer (MODIS): http://modis.psfc.nasa.
gov
National Interagency Coordination Center National
Significant Wildland Fire Potential Outlook: http://
www.predictiveservices.tiifc.gov/oiitlooks/ outlooks,
htm
NOAA Hazard Mapping System Fire and Smoke
Product: http: / /www.ospo.noaa.pov/Products/land/
hms.html
Wildland Fire/Air Quality Tools, Wildland Fire Air
Quality Response Program: http: / /tools.airfire.org
Weather
National Weather Service Fire Weather: https://
www.weather.gov/fire
National Weather Service Central Region: https://
www.weather.gov/ crh
National Weather Service Eastern Region: http://
wwwweather.gov/ erh
National Weather Service Southern Region: https://
www.weather.gov/ srh
National Weather Service Western Region: http://
wwwwrh.tioaa.gov
Information about Wildfire Smoke and
Health Effects
Wildfire Guide post-publication updates: https:/ /
airtiow.gov/wikjfire-pi.Hde-post-piiblica.tioti-iipda.tes
Air Quality Index Guide to Air Quality and Your
Health: https: / /www3.epa.pov/airtiow/a.qi
brochure 02 14.pdf
AirNow Fires and Your Health: http_s:/ /wwwairtiow.
gov/index.chii?a.ction=topics.smoke events
AirNow Smoke Advisories and Forecasts by State:
https://airoow.gov/ifidex.chii?actiofi=aimow.news
i te tn & n ews i te m i d=9 3
AirNow: https: //www.airtiow.gov
EPA Wildfires and Indoor Air Quality: https://www.
epa.pov/indoor-air-quality-iaa/wildfires-and-indoor-
56
-------
APPENDIX A
Available Factsheets as of March 2019
Recognizing the need for credible information to disseminate to the public, authors of this Guide have
developed factsheets on topics of high interest for use with the public. The factsheets will be updated as
needed and more factsheets are planned. In addition, these factsheets will become available in other languages.
So please check the current fires page of AirNow website, where you can find this document and all related
factsheets.
Prepare for Fire Season: https://www3.epa.gov/airtiow/smoke fires/prepare-for-fire-seasoti-508.pdf
Indoor Air Filtration: https://www3.epa.gov/airnow/smoke fires/indoor-air-filtration-factsheet-508.pdf
Reduce Your Smoke Exposure: https://www3.epa..p;ov/airtiow7smoke fires/reduce-ymir-s moke-exposure,
pdf
Protect Yourself from Ash: https: / /www3.epa.gov/airtiow/smoke fires /protect-yourselr-from-ash-ract-
sheefcpdt-
Protect Your Lungs from Wildfire Smoke or Ash: https: / /www3.epa.gov /airtiow/smoke fires /respirato-
ry-pro te ction-508.pdf
Protecting Children from Wildfire Smoke and Ash: https: / /www3.epa.gov/airflow/smoke fires /protect-
ing-children-from-wildfire-smoke-and-ash.pdf
Protect Your Pets from Wildfire Smoke: https: / /www3.epa.gov /airtiow/smoke fires /protect-your-pets-
fro m-wildfire-smoke.pdf
Protect Your Large Animals and Livestock from Wildfire Smoke: https: / /www3.epa.gov /airnow /smoke
fires/ protect-your-large-animals-and-livestock-from-wildfire-smoke.pdf
A-l
-------
-------
APPENDIX B
Identification and Preparation of Cleaner Air Shelters for Protection
of the Public from Wildfire Smoke
1. Identify one or more facilities with tight-sealing windows and doors and public access (for example, librar-
ies, school gymnasiums, buildings at public fairgrounds or civic auditoriums). As a rule of thumb, newer
buildings will generally be more desirable than older ones. Consider using institutional controls to limit
smoke infiltration, such as limited door and window use.
2. At a minimum, a cleaner air shelter should have central air conditioning with filtration that is at least medi-
um or high-efficiency, particularly at the fresh (outdoor) air intake(s). If needed, filters should be upgraded
prior to the fire season after assuring that the system can handle the increased airflow resistance. Building
managers should ensure that filters are properly fit and sealed to prevent air bypassing the filter media.
Filters should be regularly maintained and/or replaced according to the manufacturer's recommendations.
Even during smoke events, building managers should continue to ensure that the building is adequately ven-
tilated and that fresh air intakes have high-efficiency (MERV 13 or higher1) filters to clean the air entering
the building. Reducing or stopping fresh air intake could actually alter the building air-pressure balance and
create indoor air quality issues that could offset any benefit of reduced smoke exposure (for more informa-
tion, refer to .Appendix D.
3. Install/inspect room air cleaners where appropriate, such as in cleaner air shelters with separate, smaller
rooms (e.g. classrooms, meeting rooms). Choose room air cleaners with sufficient capacity, i.e., a tobacco
smoke Clean Air Delivery Rate (CADR) that is at least 2/3 the room volume. Choose an air cleaner with
a higher CADR for rooms with ceilings higher than 8ft. Ensure proper maintenance of air cleaners, keep
spare filters on hand, and provide instructions on changing the filter to trained personnel.
4. Assure that the facility can handle the increased cooling load due to high occupancy.
5. Install a properly calibrated carbon monoxide alarm that has a digital display and battery backup function
(available at most hardware stores).
6. Provide a radio for updates on fire status and access to a telephone in case of emergency.
7. Ensure adequate services such as restroom facilities and garbage disposal/collection.
1 Minimum Efficiency Reporting Value as determined by ASHRAE Standard 52.2: Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size
B-l
-------
-------
APPENDIX C
Technical Wildfire and Smoke Resources
The tools in this Appendix may aid public health agencies, communities, and air quality professionals in their
technical assessment of wildfires and wildfire smoke. For more information about these tools contact Peter
Lahm, U.S. Forest Service, peter.lahm@usda.gov.
Accessing Information about Active Wildfires
It's often difficult to obtain information about brand new or emerging wildfires and good information may
take a day or two (or longer) to become available. Until then, the best way to get a little news on a new wildfire
may come from scanning social media posts from state fire management agencies, county sheriff departments,
and county emergency management. Local news is often quickly onsite and can be another source of
information. The National Interagency Fire Center hosts a map that shows various incidents around the US
including satellite detected hot spots which may show the location and size estimate of a new wildfire. The
map can be accessed here: https:/ /maps.nwcg.gov.
Once a wildfire grows to the point that local fire response agencies can no longer manage it, an Incident
Management Team will be ordered. Information on a wildfire is much easier to find once one of these,
teams has arrived. Detailed information about wildfires can be accessed at the Incident Information System
(INCIWEB): https:/ /inciweb.nwcg.gov. Geographic area coordination centers (GACC's) have: more localized
information about wildfires and are another good source of information. Access your local GACC here:
https: / / ga cc.nifc.gov / index.php.
UNITED
.Nev. - *
OF AMERICA'
Figure CI. Smoke from many large fires creating haze across the western and central United States. Red dots are satellite
fire hot spot detections (NASA WORLDVIEW, September 4,2011). To learn more, see the NASA WorldviewTutorial by the
NASA Health and Air Quality Applied Sciences Team (HAQAST) at https://haqast.org/nasa-tools.
C-l
-------
(Air
AirNow
Seeing Smoke from Space
Satellites are continually viewing the planet and
often see large wildfires and the smoke emanating
from them. Satellite views can help determine where
smoke is coming from. Is it from a near-by fire, or is
it from Canada or even Siberia? It's important to note:
that the smoke seen from a satellite may be anywhere
in the atmosphere, so it could be elevated and not
affecting people at ground level. Clouds can generally
be distinguished from smoke as they show up as
bright white whereas smoke is off-white or beige with
a brownish tinge., NASA WORLD VIEW provides
access to satellite photos: https: / /worldview.
ea.rthda.ta..nasa.gov. An optional overlay layer of "fires
and thermal anomalies" shows the locations of large
fires as red spots (Figure CI)
Sometimes satellite pictures are difficult to interpret,
such as when smoke mixes with clouds. Then a
human analysis is useful, such as the NOAA Hazard Mapping System (HMS) smoke plume product. The
analysis tells you where smoke is light (green), medium (yellow), or heavy (red). The Current Fires page on the
AirNow website uses shades of gray to display the smoke plumes trom the X( ).\ \ I IMS (Figure C2).
AirNow-Tech
AirNow has a decision support tool called AirNow-Tech (airnowtech.org). which allows partner agencies
to manage, quality control, query, and visualize not only their data but also a national dataset of air quality,
meteorological and satellite information. One powerful AirNow-Tech tool for wildfire evaluation is Navigator
GIS. Navigator allows the user to Overlay meteorological, fire, and satellite data over air quality observations.
In addition, users can run trajectories on any point of the display to see air parcel projections or for post
wildfire event analysis (Figure C3).
Parameter
PM2.5 - Principal-PM25
Duration
1 Hr
POC
Principal
0 Parameter CH Hide Concentrations
0 Wind Barbs
0 HMS Fire 0 HMS Smoke
Legend
PM2.5 - Pri nci pal - P M25/1 Hr (ug/m3)
-5.0to < 10.0
O 10.0to <20.0
O 20.0 to < 30.0
Figure C3. AirNow-Tech Navigator
C-2
Figure C2. Smoke plumes from NOAA Hazard Mapping
System. See more about the NOAA HMS here: https://
www.ospo.noaa.gov/Products/iand/hnns.htmi.
-------
U.S. Forest Service/Interagency Wildland Fire Air Quality Response Program Tools
The U.S.; Forest Service Research AirFire Team and the Wildland Fire Air Quality Response Program have
developed a number of tools and on-line resources to aid in summarizing monitoring data and
making smoke dispersion predictions. These tools, plus others under development, are available here:
https://wildla.ndfiresmoke.net/tools. These are some of the fundamental tools used by Air Resource Advisors
assigned to wildfires.
Particulate (PM2J Monitoring Website Tool
The Particulates Monitoring Website Tool (https: / /tools.airfire.org/monitoring) provides easy-to-use, rapid
access to particulate air quality monitoring data from publicly available permanent monitoring sites across
the United States and from temporary monitoring instruments set up during wildland fire incidents. Users
Monitoring v4.1
(?) Reload for map updates. Disclaimer: Data are preliminary and provided for informational purposes only. See original sources for final values. Not for official use; use at own risk.
O CO * Edmcj
CANADA
Latest NowCast
NowCast Timeseries
Shown in local time
Agness-4156 Agness Rd
last 3 t J days
GEW0ฎ GREATCLMj&M^
I
l.t>*
UNIT I.
Weaverville-33 Court St
Gasquet-Gasquet RS Rd
ll*h.b.lh llUb-
Leaflet | Powered by Esri | Esri, HERE, Garmin, NOAA, USGS. FAO, EPA, AAFC, NRCan
ฉ Monitor Type
) Permanent monitors
\ Temporary monitors
ฉ NowCast
| Hazardous
| Very Unhealthy
| Unhealthy
| Unhealthy for Sensitive
Groups
i Moderate
| Good
no data
) Last Updated
AirNow: 10/0123:15 UTC AIRSIS: 10/0123:16 UTC WRCC: 10/0123:19 UTC
Selected Monitors: 3 monitors from 1 timezones.
I2T Data Report Qf CSV File Gf AQI-NowCast
Agness-4156 Agness Rd
Monitor ID: lon_.124.058_lat_42.553_wrcc.s215
Soure: WRCC
Latest NowCast PM2 5:21.4 Mg/m3
Contains data through 2018-10-0123:00:00 UTC
Timezone: America/Los_Angeles
QA/QC: I2f Report
EfShow in Simple Interface
7 -%
L
a yu
Figure C4. PM2, monitoring web tool display example. Current fine particulate NowCast conditions are shown on the map.
Selecting monitors of interest reveals a multi-day NowCast time series and other graphics. Access at https://tools.airfire.orp/
monitoring.
C-3
-------
BlueSky Daily Runs*
Domain View
Production Run Status Custom Run Status
CONUS 0.15deg 192hrs (2018-08-05 00Z)
8/10/2018 7:00! Pacific i ] S DST
PM 2.5
Hourly
3-Hour Running Average
Daily Maximum
Daily Average
Fire Information
< Modelled Fires
ฎ Flames
Circles
Other
0 Region Bounds
Seattle o ~
m
ju
- ..
i
Legend
NORTH DAKOTA
50LTH DAKOTA
l. L.r-; Lai, Vegas
o
*
Los Angeles
o
San Diegon #
Tijuana .
GREAT PLAINS
NEBRASKA
S TATE S
KANSAS
Toronto-.,
Milwaukee Grand Rapids o Roch
Delioi!0 Buffalo
Chicago0 MICHIGAN L
Pittsburgh^
Indianapolis Columbus ^
IND&na Cincinnati . *
Louisville
KENTUCKY
VIRGINIA
Richmond
Nashville o Knoxville.fr Raleigh
TENNESSEE Charlrtte + NORTH
NEW MEXICO
New Orleans
FLOR IDA o Jacksonville
Orlando
JpTampa
TorreGn 4#
I I' lit- ii-
Figure C5. BlueSky daily smoke model run for the Continental United States (CONUS) shown in the web viewer version.
KMZ and other output formats are also available at https://tools.airfire.org.
Figure C6. BlueSky hourly average surface smoke predictions at I am on 811912018 at 3 grid resolutions: (a) 1.33
km, (b) 4 km, and (c) 12 km in north central Washington. Higher resolution versions (a and b) allow the effect of
complex terrain to be better reflected in smoke concentration estimates. KM LI Google Earth version.
C-4
-------
can select monitors from a map and view time-series data in a number of plots showing daily averages, hourly
NowCast values, and diurnal smoke impact patterns. Multiple monitors of interest can be selected, and once
selected bookmarking the site's URL allows users to share this list with others or to quickly return to this
specific set of monitors and view updated air quality measurements.
Currently the tool displays fine particulate measurements (PM25), but other pollutants may be added in the
future. The tool uses public data made available from EPA's AirNow-Tech system (https:/ /atrti owfech.org).
monitoring data from a national cache of temporary monitors that are deployed during wildfire incidents, plus
any additional monitoring data made available by originating agencies as long as the source data has not been
tagged as "private"2 (Figure C4).
BlueSky Daily Smoke Model Runs
Predicting air quality impacts from active wildfires depends on linking together information and models to
estimate fire size, fuel type, fuel consumption, smoke plume rise, weather, atmospheric dispersion, and ground-
level smoke concentrations. One commonly used smoke tool developed by the Forest Service AirFire Research
team is the BlueSky smoke modeling framework. Multiple versions of BlueSky run automatically each day with
daily updates of fire and weather information. BlueSky combines basic fire information with available fuels
maps (from the USFS Fire Characteristic Classification System [FCCS]) and current fuel moisture conditions
(from the USFS Wildfire Information Management System [WIMS]), to compute fuel consumption (via the
USFS CONSUME model) and emissions before computing plume rise and dispersion. Two different plume
and dispersion models are used - a simple LaGrangian dispersion model with no chemistry (HYSPLIT), and the
Community Multiscale Air Quality Modeling System (CMAQ). CMAQ is run in two modes; limited chemistry,
or as a full photochemical model with all sources. Multiple geographic domains, weather models, weather
model resolutions, and dispersion models combine to result in approximately 30 separate iterations for a user to
choose from (Figure C5). All runs can be accessed at https://tools.airfire.org.
BlueSky relies on meteorological models with high resolution grids in order to better estimate local smoke
effects. Currently the most fine-scale meteorological models used by BlueSky on a daily basis have a resolution
of 1.33 km enabling predictions of smoke movement to reflect the effects of complex terrain (Figure (36).
High resolution versions of BlueSky are available for the Pacific Northwest, California/Nevada, Arizona, and
Alaska. National grids at 3-km resolution are available, as are combined Canada/CONUS grids. Movable,
high-resolution meteorological grids (1.27 km) can be placed over areas of concern during the western wildfire
season when made available by the National Weather Service. All model runs are viewable on a simple web map
with options for 1-hour, 3-hour, and daily (24-hour) smoke estimates. Typical forecasts extend for 23 days into
the future. KMZ files for use in Google Earth are available for download.
2 Occasionally states set up special purpose monitoring studies where the data is not publicly available.
C-5
-------
-------
APPENDIX D
Guidance on Protecting Workers in Offices and Similar Indoor Workplaces from
Wildfire Smoke (Adapted from Cal/OSHA)
Wildfire smoke can be a hazard for people who work in office and commercial buildings many miles from
evacuation zones. Environmental and public health agencies have advised people to consider setting air
conditioners in their homes to recirculation mode, if possible, in order to reduce the intake of pollutants.
Subsequently, people have asked whether to apply this advice to limit the introduction of outdoor air
applies to office and commercial buildings. Eliminating or substantially reducing the outdoor air supply in
office buildings and other indoor workplaces as a first step to reduce exposure to smoke is generally not
recommended.
The ventilation systems in office buildings and other commercial buildings are more complicated than home
air-conditioning systems. Changing the outdoor air supply in public and commercial buildings can adversely
affect other essential functions of the building. These buildings typically have heating, ventilating and air
conditioning systems (HVAC systems) that bring outside air into the building through filters, blend it with
building return air, and thermally condition the air before distributing it throughout the building. These
buildings also have exhaust air systems for restrooms and kitchens, and may also have local exhaust systems for
garages, laboratory fume hoods, or other operations. These exhaust systems require makeup air (outdoor air) in
order to function properly. Also, without an adequate supply of outdoor air, these systems may create negative
pressure in the building. Negative pressure will increase the movement of unfiltered air into the building
through any openings, such as plumbing/sewer vents, doors, windows, junctions between building surfaces, or
cracks. In general, buildings should be operated at slight positive pressure in order to keep contaminants out,
and to help exhaust air systems function properly.
HVAC systems should be operated continuously while occupied in order to provide the minimum quantity of
outdoor air for ventilation, as required by the standards or building codes to which the building was designed.
For many office buildings, this is often in the range of 1520 cubic feet per minute (cfm) per person, although
it could be less in older buildings.3
Using the HVAC System(s) to Protect Building Occupants from Smoke
As a first step to protect building occupants from outdoor air pollution, including the hazardous conditions
resulting from wildfire smoke, building managers and employers should ensure that the HVAC system's filters
are not dirty, damaged, dislodged, or leaking around the edges. Before the wildfire season, or during smoke
events if necessary, employers and building operators should ensure that a qualified technician inspects the
HVAC systems, makes necessary repairs, and conducts appropriate maintenance. Filters should fit snugly in
their frames, and should have gaskets or sealants on all perimeter edges to ensure that air does not leak around
the filters.
Building operators should consider installation of the highest efficiency filters that do not exceed the static
pressure limits of the HVAC systems, as specified by the manufacturer or system designer4. Pressure gauges
3 Cal/OSHA regulations C8 CCR 5142) require that HVAC systems be operated continuously while occupied in order to provide the minimum quantity of outdoor air
required by the state building code at the time the building permit was issued. These regulations are currently found in the California Code of Regulations, Title 24, Section
121. For most buildings, this quantity is 15 cubic feet per minute (cfm) per person.
4 Many existing HVAC systems should be able to accommodate pleated, medium-efficiency filters with particle removal ratings of MERV 5 to 12, and some may be able
to use high-efficiency filters with ratings of MERV 13 or higher. Consider a low-pressure HEPA filter (MERV 17 plus) if the building occupants have respiratory or heart
D-l
-------
should be installed across the filter to indicate when the filter needs replacing, especially in very smoky or dusty
areas. Indoor contaminants can be further reduced by using stand-alone high-efficiency particulate air (HEPA)
filtering units. For more information on air cleaners, see the California Air Resources Board webpage at:
httt?s: / /www.arb.ca.goy/research/indoor/aircleaners/ consumers, htm.
In some circumstances it may be helpful to reduce the amount of outdoor air in order to reduce smoke
pollution inside the building, while still maintaining positive pressure in the building. Temporary reductions in
outdoor air flow rates might be considered when all of the following conditions are met:
1. The local outdoor air quality for particulate matter meets the EPA Air Quality Index definition of Un-
healthy, Very Unhealthy, or Hazardous due to wildfire smoke.
2. A qualified HYAC technician has inspected the HVAC systems and ensured that the filters are functioning
properly, that the filter bank is in good repair, and that the highest feasible level of filtration has been pro-
vided. This should be documented in writing.
3. A qualified HYAC technician or engineer has assessed the building mechanical systems and determined, in
writing, the amount of outside air necessary to prevent negative pressurization of the building, and to suf-
ficiently ventilate any hazardous processes in the building (such as enclosed parking garages or laboratory
operations).
4. The HVAC systems are operated continuously while the building is occupied to provide at least the mini-
mum quantity of outdoor air needed, as determined by the HVAC technician or engineer in Item 3 above.
The employer or building operator ensures that the systems are restored to maintain the minimum quantity of
outdoor air for ventilation, as required by the standards or building codes to which the building was designed, no
later than 48 hours after the particulate matter levels fall below the levels designated by the EPA as Unhealthy.
Other Actions to Protect Employees from Wildfire Smoke
In addition to assessing and if necessary modifying the function of the HVAC system, employers are
encouraged to take other reasonable steps to reduce employee exposure to smoke, including alternate work
assignments or relocation and telecommuting. Some buildings rely on open windows, doors, and vents for
outdoor air, and some may have mechanical ventilation systems that lack a functioning filtration system
to remove airborne particles. In these cases, the employees may need to be relocated to a safer location.
Employees with asthma, other respiratory diseases, or cardiovascular diseases, should be advised to consult
their physician for appropriate measures to minimize health risks.
Respirators, such as N95s and other filtering facepiece respirators, may provide additional protection to some
employees against environmental smoke. Employees whose work assignments require the use of respirators
must be included in a respiratory protection program (including training, medical evaluations, and fit testing).
Additional Information
The Lawrence Berkeley National Laboratory has produced a multi-page summary on air cleaning and its effects
on health and perceived air quality, which can be found at: hftos: / /iaqscience.lbl.yov/air-summarv
disease conditions, or if the building experiences frequent wildfire episodes.
D-2
-------
APPENDIX E
Hazards during Cleanup Work Following Wildfires from National Institute for
Occupational Safety and Health (NIOSH)
The purpose of this section is to discuss some of the health and safety hazards that homeowners and workers
may encounter after a wildland fire. This document is not designed to address health and safety for fire fighters
or other emergency response workers during a wildfire or other emergency event.
After a wildfire has ended, cleanup and recovery activities are often needed. These activities may pose
health and safety hazards that require necessary precautions. In most cases, it may be more appropriate for
professional cleanup and disaster restoration companies, rather than homeowners or volunteers, to conduct
this work. Although the types of hazards may be different for each wildland fire, some common hazards
include:
1. Contact with fire.
After a wildfire, trained fire fighters will make sure the fire is completely out. If there is any chance the
wildfire could reignite, leave immediately and notify emergency personnel.
2. Burnt and unstable structures.
Be aware of unstable and damaged houses and other structures after a wildfire. Do not assume that these
areas are safe or stable because damage may not be noticeable and can create a risk for serious injuries from
slips, falls, punctures, or being struck by collapsing materials.
Safety Measures
To prevent injuries from burnt and unstable structures:
Conduct a thorough inspection and identify and eliminate hazards before conducting any work. Avoid
work around fire-damaged structures, including stairs, floors, and roofs, until an engineer or architect
examines and certifies the structure is safe.
Wear personal protective equipment, including long sleeved shirts and pants, hard hats, safety glasses,
leather gloves, and steel toe boots, to reduce the risk of injury.
Leave immediately if a structure shifts or makes an unusual noise that could signal a possible collapse.
3. Burnt and unstable trees. Another common hazard after a wildfire is unstable trees, known as 'snags' or
'hazard trees,' which can fall and injure homeowners and workers. It is important to assess the stability of
all trees before working and driving around them.
Safety Measures
Always contact a professional to evaluate a tree's stability and to safely remove any suspected hazardous
trees from the property and along roadways before conducting cleanup work.
For more information about potential hazards from tree removal, see: Preventing Chain Saw Injuries
During Tree Removal After a Disaster (https: / /www.cdc.p~ov/disasters /chainsaws.html).
E-l
-------
4. Carbon monoxide.
Wildland fire cleanup activities may involve the use of gasoline or diesel powered pumps, generators, and
pressure washers. This equipment releases carbon monoxide (CO), a deadly, colorless, odorless gas. It is
important that homeowners and workers protect themselves from CO poisoning.
Safety Measures
To avoid the risk of CO poisoning:
Never bring gas or diesel powered machines indoors.
Only operate these machines in well-ventilated areas.
Do not work near exhaust gases (CO poisoning can occur even outdoors near exhaust from engines that
generate high concentrations of CO).
Shut off the equipment immediately and seek medical attention if you experience symptoms of CO
poisoning.
To learn more, visit NIOSH's webpages: Carbon Monoxide (httns:/ /www.cdc.P'ov/niosh/topics/co-
co mn /) or Carbon Monoxide Hazards from Small Gasoline Powered Engines (httns: / /www.cdc.p-ov/
niosh/topics/co/).
5. Confined spaces.
A confined space is an area that has limited openings for entry or exit, has limited air flow and is not de-
signed for human occupancy. Examples of confined spaces include septic tanks, storage tanks, utility vaults
and wells. These spaces may contain toxic gases, may not have oxygen, or may be explosive. In many cases,
these hazards are not easily recognized without proper training and equipment.
Safety Measures
Never enter a confined space without proper training and equipment, not even to rescue a fellow worker.
Contact the local fire department for help.
To learn more, visit NIOSH's webpage: Confined Spaces (https://www.cdcgov/niosh/topics/confined-
space/).
6. Fatigue and stress.
A homeowner may experience emotional stress and mental and physical fatigue from cleanup and from
loss of personal property or valuables. Fatigue and stress may increase the risk of injury and illness.
Safety Measures
After a fire, homeowners or other workers may need to:
Seek emotional support from family members, neighbors, and local mental health care workers to help
prevent more serious stress-related problems.
Set priorities for cleanup tasks and pace work over days or weeks to avoid physical exhaustion.
Rest and take frequent breaks to avoid exhaustion.
Begin a normal sleep and eating schedule as quickly as possible.
Take advantage of disaster relief programs and services in the community.
Understand physical and mental limitations.
E-2
-------
To learn more, visit NIOSH's webpages: Traumatic Incident Stress: Information For Emergency Re-
sponse Workers (httos: / /www.cdc.yov/niosh/mining/works /coversheet643.html) and Stress at Work
(htfrps://www.cdc.PT)v/niosh/tonics/stress/).
7. Electrical dangers.
One common danger after a fire is a downed/damaged power pole with potentially energized power
lines laying on the ground or hanging from the pole. Any type of work with power lines or other electri-
cal sources must only be conducted by trained professionals, such as electricians and utility workers. If a
potential electrical danger or a downed power line is identified, avoid all electrical hazards by stopping work
and immediately notifying the local utility company.
Safety Measures
When working near power lines, it is important to follow these steps to prevent electrical injuries:
Do not work or enter any area with any potential for electrocution from a power line or other electrical
hazards.
Treat all power lines and cables as energized until proven otherwise.
When the power is off, never restore power until a professional inspects and ensures the integrity of the
electrical system.
Do not use electrical equipment that has been exposed to heat from a fire until checked by an electrician.
Unless power is off, never enter flooded areas or touch electrical equipment if the ground is wet.
Use extreme caution when equipment is moved near overhead power lines. For example, contact between
metal ladders and overhead power lines can cause serious and often fatal injuries.
Do not stand or work in areas with thick smoke. Smoke hides electrical lines and equipment.
To learn more, visit NIOSH's Electrical Safety page: (httns://www.cdc.g'ov/niosh/tonics/electrical/).
8. Hazardous and other potentially dangerous materials.
Many homes and other structures may contain or store hazardous materials and chemicals. Some common
materials include asbestos, lead, pesticides, propane, and gasoline. These materials may cause health effects,
may be explosive, or may react with other chemicals. Before beginning cleanup activities, contact a profes-
sional who is familiar with hazardous materials to determine the different types of hazards that are present
and how to safely clean up and dispose of them in accordance with local and state laws.
Safety Measures
To reduce the chance of exposure to hazardous and other dangerous materials:
Be cautious of chemicals, propane tanks, and other dangerous materials.
Wear protective clothing and gear when handling hazardous materials.
If exposed to hazardous materials, wash the affected area (e.g., skin, eyes) and contact your local poison
control center or the American Association of Poison Control Centers at 1 (800) 222-1222. Seek medical
care immediately if the exposure is severe or you experience symptoms.
Homes built before 1980 may contain asbestos and lead. Contact your county health department to learn
about local laws and regulations. Because disturbing lead and asbestos may result in serious health con-
sequences, it is recommended that only trained professionals test for and clean up materials that contain
lead or asbestos.
E-3
-------
Fires may also damage tanks, drums, pipes, or equipment that may contain hazardous materials, such as
pesticides, gasoline, or propane. Before opening or removing containers that may contain hazardous ma-
terials, contact the local fire department or a hazardous materials team to help assess and remove hazard-
ous waste.
To learn more about chemical safety, visit NIOSH webpages: Pocket Guide to Chemical Hazards
(https:/ /www.cdc.P'Ov/niosh/nop;/) and Chemical Safety (https:/ /www.cdc.P'Ov/titosh/topics/chetnt-
cal-safety / defaulthtrril).
9. Hot environments.
While working in hot weather, homeowners and cleanup workers could be at risk for heat-related illnesses,
such as heat stress, heat rash, heat cramps, and heat stroke. It is important to be aware of the symptoms of
heat related illness, how the illness can affect health and safety, and how it can be prevented.
Safety Measures
To reduce the potential for heat related illnesses, it is important to follow some basic work practices,
such as:
Wearing lightweight, light-colored, loose-fitting clothes,
If possible, blocking out direct sun or other heat sources,
Taking frequent breaks in cool, dry areas,
Acclimatizing before working (getting used to weather conditions),
Working during the cooler hours of the day when possible, and
Maintaining hydration by drinking plenty of water and other fluids.
If a homeowner or worker displays any signs of heat related illness, it is important to immediately go
to a cool, shaded place, sit or lie down, and drink water. If possible, cool water may be poured over the
homeowner's or worker's head and body. Seek medical attention immediately if the symptoms do not
subside.
To learn more, visit NIOSH's webpage: Heat Stress (https://www.cdc.gov/niosh/topics/heatstress/).
10. Musculoskeletal injuries.
Homeowners and workers who may be involved in cleanup activities are at risk for developing stress, strain,
and potential musculoskeletal injuries, which are injuries or disorders of the muscles, nerves, tendons,
joints, cartilage, or spinal discs. These common injuries can occur when moving debris and materials, using
hand-held equipment (e.g., chainsaws) due to repetition, force, vibration, or awkward postures.
Safety Measures
Some useful tips to prevent these injuries:
Use teams of two or more to move bulky objects.
Take breaks when conducting repetitive work, especially if experiencing fatigue.
Avoid working in unusual or constricting postures.
Use correct tools and equipment for the job and use them properly.
E-4
-------
Do not lift material weighing 50 pounds or more and use automated lifting devices for heavier objects.
Be sure the area is clear of slip, trip and fall hazards.
To learn more, visit NIOSH's webpage: Ergonomics and Musculoskeletal Disorders (htlps:/ /www.cdc.
p'ov/tiiosh/topics / ergonomics /).
11. Wildfire smoke and ash
Smoke from a wildland fire can pose health risks. Older adults, young children or individuals with underly-
ing heart or lung disease are the most likely to be affected by inhaling wildland fire smoke. Healthy indi-
viduals may also experience short-term respiratory irritation symptoms, such as burning eyes and runny
nose. If there is smoke in the area, homeowners and cleanup workers who are at-risk of experiencing a
smoke-related health effect should consider leaving the area until the smoke clears.
Ash from wildland fires can be deposited on indoor and outdoor surfaces in areas around the fire and can
be irritating to the skin, nose and throat, and may cause coughing.
Safety Measures
To minimize the health effects that may occur due to exposure to smoke and ash:
Always wear proper personal protective equipment (long sleeve shirts, pants, gloves and safety glasses)
when working around ash. If you do get ash on your skin, wash it off as soon as possible.
Do not use leaf blowers or take other actions (e.g., dry sweeping) that will put ash into the air. Shop vac-
uums and other common vacuum cleaners do not filter out small particles, but rather blow the particles
out the exhaust into the air. To clean up ash, use vacuums equipped with High Efficiency Particulate Air
(HEPA) filters.
Do not consume any food, beverages, or medication that has been exposed to burn debris or ash.
Well-fitting respirators may provide some protection during cleanup. Please visit NIOSH's Respirator
Trusted-Source Information web site at: http://www.cdc.gov/tiiosh/npptl/topics/respirators/disp
part/ Re s p S ou rce. h tin 1.
If the presence of asbestos, lead, CO or other hazardous material is suspected, do not disturb the area.
Dust masks or filtering facepiece respirators do not protect against asbestos or gases such as CO.
Avoid burned items that may contain hazardous chemicals, such as cleaning products, paint and solvent
containers.
Avoid ash from wooden decks, fences, and retaining walls pressure treated with chromated copper arse-
nate (CCA) as it may contain lethal amounts of arsenic.
12. Working with and around heavy equipment.
Do not operate heavy equipment, such as bulldozers, backhoes, and tractors, unless you are properly
trained. Serious and fatal injuries can occur when equipment is used improperly. To learn more about
motor vehicle safety, visit NIOSH's webpages: Motor Vehicle Safety dittos://www.cdc.gov/tiiosh/motor-
vehicle / de bin 11htmI) and Fatality Assessment Control and Evaluation (httns://www.cdc.gov/tiiosh/fa.ce/
deb.ulthtml).
13. First aid
First aid, even for minor cuts and burns, is extremely important as workers are exposed to smoke and
burned materials. For more information, please visit NIOSH's webpage: NIOSH's First Aid Procedures
(httns:/ /www.cdc.p'ov/ tiiosh/tipp7firsta.id.html).
E-5
-------
United States Office of Air Quality Planning Publication No. EPA-452/R-19-901
Environmental Protection and Standards August 2019
Agency Health and Environmental
Impacts Division
Research Triangle Park, NC
-------
-------
CALIFORNIA
AIR RESOURCES BOARD
wmBm
2A Kb ***
ซ'* *
U#S
4>EPA
United States
Hnvironmental Protection
Agency
------- |