How to protect structural firefighters responding to WUI fires

By Wesley R. Attwood, Richard E. Evoy, Stephen J. Ringer, Andrea F. Wilkinson, Emily J. Haas, and Jay L. Tarley

Fire departments across the country are increasingly responding to wildland-urban interface (WUI) fires.[1] These fires occur in transition areas between natural environments and human development where vegetative and wildland fuels meet structures. They include forest, grass, or brush fires that are increasing in size and intensity.[2]

While the characteristics of WUI fires are different than those of structure fires, there are steps that fire departments can consider to protect the safety and health of structural firefighters who are expected to respond to WUI fires.

Historically, the National Institute for Occupational Safety and Health’s Fire Fighter Fatality Investigation and Prevention Program (FFFIPP) has conducted independent investigations of firefighter line-of-duty deaths (LODDs) and serious injuries, including WUI fires.[3] Publicly available reports summarize findings and include actions to help prevent similar events.

Based on a review of 13 previous investigation reports that involved WUI fires [3], we highlight three actions fire departments can consider to reduce risk to structural firefighters who respond to WUI fires:

1. Provide wildland or WUI firefighting training that includes knowledge of the wildland environment, familiarity with tools/equipment, fire behavior, and firefighting tactics.
2. Provide appropriate personal protective equipment (PPE), including wildland firefighting PPE and approved fire shelters.
3. Implement and deliver comprehensive health-related fitness programs.

Training

The WUI environment and its hazards are unique. The introductory training that most structural firefighters receive does not include preparation or safety considerations for WUI or wildland fires. According to the National Fire Protection Association (NFPA), 88% of fire departments across the United States respond to WUI fires, but only 40% of these departments provide WUI fire training [4, 5]. In our review of the 13 FFFIPP reports (listed at the end of this article as a separate reference list), many fire departments did not have written standard operating procedures or guidelines requiring training for WUI or wildland fires. NFPA 1051: Standard for Wildland Firefighting Personnel Professional Qualifications establishes the basic knowledge and skills needed for firefighters who respond to these incidents.[6]

Fire departments can provide structural firefighters, who may respond to WUI fires, with wildland or WUI firefighting training. Appropriate training modules may include:

• Fire suppression and conservation activities in forests, grasslands, brush, and other vegetation that are involved in fire but is not within buildings or structures.
• Understanding weather forecasts and observing weather changes, so a firefighter can adjust operations and tactics.[7]

The National Wildfire Coordinating Group (NWCG) offers online, in-person, and hybrid wildland firefighting training [8]. This includes introductory level courses and advanced training that cover specialized wildland firefighting activities. Additionally, firefighters can participate in training that focuses directly on the WUI. For example, the U.S. Fire Administration previously offered a course on WUI firefighting for structural firefighters that includes operational activities and safety considerations for WUI fire suppression activities.[9] These trainings include information about:

• The 2025 Incident Response Pocket Guide (IRPG), which establishes standards for wildland fire incident responses and provides firefighters with guidelines for operations, tactics, and hazards in the fire environment [10].
• Best practices such as the 10 Standard Firefighting Orders, 18 Watch Out Situations, and the principle of Lookouts, Communications, Escape Routes, and Safety Zones.

Use of appropriate PPE

NFPA 1977: Standard on Protective Clothing and Equipment for Wildland Fire Fighting and Urban Interface Fire Fighting provides the requirements for wildland and WUI firefighting PPE. This includes protective garments, helmets, gloves, footwear, goggles, and other specialized PPE such as load-carrying equipment and ballistic nylon chaps or other chainsaw cut resistant protection for lower extremities. This NFPA standard also provides information on fire shelters, which are critical when firefighters are overrun by a fire with no option for escape. Fire shelters protect firefighters by reflecting radiant heat and trapping breathable air.[11] NFPA 1550: Standard for Emergency Responder Health and Safety recommends that members who perform wildland firefighting be trained at least annually in the proper deployment of approved fire shelters.[12]

In some of the FFFIPP investigations, such as F2000-22 and F2010-35, firefighters used structural firefighting PPE during the incident including turnout coats and pants. This type of PPE can negatively affect firefighters when used for WUI fires that involve harsh environmental factors and long durations. Extinguishing WUI fires often requires more physical activity than structure fires. Structural firefighting PPE can trap heat preventing heat loss from the skin which can cause a firefighter’s core temperature to rise. This occurrence contributed to overexertion and cardiac arrest in some of the FFFIPP investigations (e.g., F2010-01 and F2011-24). Wildland firefighting PPE is designed to let heat out, not keep it in. In other FFFIPP investigations, firefighters wore a combination of structural firefighting pants and boots with non-fire-resistant long sleeves or tee shirts. This allowed direct skin exposure to fire and heat resulting in burn injuries.

Firefighters can reduce risk by using appropriate protective clothing and respiratory protection for the specific hazard or incident they encounter. This includes training on the use and care of their assigned PPE, including its limitations. Routine inspection and maintenance of PPE is critical to ensure its effectiveness and longevity.[13, 14] Response to WUI fires may also increase risk of exposure to hazardous particulates and gases, including some carcinogens that can be inhaled or absorbed through skin. To date, no wildland fire respirators are NIOSH Approved® that protect against all inhalation hazards identified and meet requirements outlined in NFPA 1984: Standard on Respirators for Wildland Fire-Fighting Operations and Wildland Urban Interface Operations. NIOSH has approved respirators that address most hazards identified in NFPA 1984, except for acrolein, and carbon monoxide, which can pose significant risks to the health and safety of wildland firefighters. A NIOSH Approved respirator that provides protection against the hazards present at a WUI fire should be used as part of an overall respiratory protection program (29 CFR 1910.134) [15].

Comprehensive health-related fitness programs

Firefighting is strenuous and labor-intensive. WUI fires specifically can encompass acres of land, last for long periods of time, and include harsh environmental factors with rugged and steep terrain. Extinguishing these fires requires firefighters to exert and endure a great amount of physical activity. As such, some of the FFFIPP investigations suggest that fire departments develop health-related fitness programs to improve firefighters’ physical ability. NFPA 1583: Standard on Health-Related Fitness Programs for Fire Department Members establishes criteria and offers considerations for these programs to assist firefighters in developing and maintaining a level of health and fitness to safely perform assigned functions.[16]

Wildfire risk reduction efforts

In one investigation (F2003-36), NIOSH reported that authorities having jurisdiction may consider developing guidelines and community plans for managing fuels in the WUI. Federal agencies, such as the Bureau of Indian Affairs, have suggested that managing fuels within the WUI be prioritized.[17] This includes identifying and clearing dead vegetation, debris, and other potential fire fuels surrounding structures in the WUI. These efforts may reduce the risk of unwanted fires to communities, thus increasing public and firefighter safety. Managing fuels can be a collaborative effort between fire departments and authorities having jurisdiction and can involve public fire and life safety education as well as operational efforts such as prescribed burning.[18]

Outlook

As the wildland fire season continues to grow longer and involve increasingly complex fires, the importance of preparation through education and training also increases. Despite uncertainties of WUI fire behavior, applying lessons learned from previous investigations, such as the 13 reviewed and used in this article, could have lasting impacts for more effective and safer fire department responses.

Disclaimer: The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention.

REFERENCES

1. National Association of State Foresters [2022]. Communities at risk: fiscal year 2021. Washington, DC: National Association of State Foresters.
2. USFA [2022]. What is the WUI? Emmittsburg, MD: U.S. Department of Homeland Security, U.S. Fire Administration.
3. National Institute for Occupational Safety and Health [2025]. About the FFFIPP.
4. NFPA [2017]. Wildland/urban interface: Fire department wildfire preparedness and readiness capabilities. Quincy, MA: National Fire Protection Association.
5. IAFF [n.d.]. Responding to the interface (RTI) training. Washington, DC: International Association of Fire Fighters.
6. NFPA [2020]. NFPA 1051: Standard on wildland firefighting personnel professional qualifications. Quincy, MA: National Fire Protection Association.
7. NWCG [n.d.]. Weather: Observing fire weather. Washington, DC: National Wildfire Coordinating Group. ting Group.
8. NWCG [n.d.]. NWCG Training Catalog.
9. USFA [2022]. Wildfire and the wildland urban interface (WUI). Emmittsburg, MD: U.S. Department of Homeland Security, U.S. Fire Administration.
10. NWCG [2025]. Incident Response Pocket Guide.
11. NFPA [2022]. NFPA 1977, Standard on protective clothing and equipment for wildland fire fighting and urban interface fire fighting. Quincy, MA: National Fire Protection Association.
12. NFPA [2024]. NFPA 1550: Standard for emergency responder health and safety. Quincy, MA: National Fire Protection Association.
13. NFPA [2020]. NFPA 1851: Standard on selection, care, and maintenance of protective ensembles for structural fire fighting and proximity fire fighting. Quincy, MA: National Fire Protection Association.
14. NFPA [2019]. NFPA 1852: Standard on selection, care, maintenance of open-circuit self-contained breathing apparatus (SCBA). Quincy, MA: National Fire Protection Association.
15. Occupational Safety and Health Administration. (n.d.). Respiratory protection standard, 29 CFR 1910.134. U.S. Department of Labor.
16. NFPA [2022]. NFPA 1583: Standard on health-related fitness programs for fire department members. Quincy, MA: National Fire Protection Association.
17. BIA [n.d.]. Hazardous fuels reduction management program. Washington, DC: U.S. Department of the Interior, Bureau of Indian Affairs.
18. Volker CR, Helmers DP, Kramer HA, Mockrin MH, Alexandre PA, Bar-Massada A, Butsic V, Hawbaker TJ, Martinuzzi S, Syphard AD, and Stewart SI [2018]. Rapid growth of the US wildland-urban interface raises wildfire risk. Proceedings of the National Academy of Sciences of the United States of America 115(13): 3314-3319.

FFFIPP reports referenced

• NIOSH [1999]. Two volunteer fire fighters die while fighting a wildland fire – Kentucky. By Braddee RW and Cortez K. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 99 F-14.
• NIOSH [2000]. Volunteer fire fighter killed during wildland/field fire - Indiana. By Braddee RW and Romano NT. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 99 F-35.
• NIOSH [2000]. Wildland fire claims the life of one volunteer fire fighter and injures
• another fire fighter - South Dakota. By Mezzanottee TP and Braddee RW. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2000-22.
• NIOSH [2003]. Volunteer fire fighter dies during wildland fire suppression -
• South Dakota. By Braddee RW. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2002-37.
• NIOSH [2005]. Career fire fighter was killed and a career captain was severely injured during a wildland/urban interface operation – California. By McFall MF, Braddee RW, and Hales TR. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2003-36.
• NIOSH [2007]. Volunteer fire fighter is killed and another volunteer fire fighter is injured at a wildland/urban interface fire – Oklahoma. By McFall MF and Tarley JL. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2006-10.
• NIOSH [2010]. Lieutenant suffers sudden cardiac death at scene of a brush fire – Missouri. By Smith DL and Hales TR. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2010-01.
• NIOSH [2011]. Fire fighter suffers sudden cardiac death while fighting wildland fire – Virginia. By Baldwin TN and Hales TR. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2010-35.
• NIOSH [2011]. Fire fighter suffers heart attack while fighting grass fire and dies 2 Days later – California. By Baldwin TN and Hales TR. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2011-01.
• NIOSH [2011]. Volunteer fire fighter dies and 5 volunteer fire fighters are injured during wildland urban interface fire – Texas. By Tarley JL, Loflin ME, and Campbell C. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2011-09.
• NIOSH [2012]. Volunteer fire fighter dies and three fire fighters are injured during wildland fire – Texas. By Tarley JL, Loflin ME, and Campbell C. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2011-10.
• NIOSH [2012]. Captain collapses at a structure/grass fire and dies 9 days later – Oklahoma. By Baldwin TN and Hales TR. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2011-24.
• NIOSH [2019]. One fire fighter dies and one fire fighter burned during firefighting operations at a grass fire-Texas. By Loflin ME. Morgantown, WV: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, F2018-07.

ABOUT THE AUTHORS
Wesley R. Attwood, DrCJ, is an Investigator and Program Advisor in the NIOSH Fire Fighter Fatality Investigation and Prevention Program within the Division of Safety Research and is a Coordinator for the NIOSH Public Safety Program.

LT Richard E. Evoy, PhD, MPH, is a Lieutenant with the United States Public Health Service and Research Epidemiologist in the NIOSH Western States Division.

Stephen J. Ringer, AAS, FO1, is an Investigator with the NIOSH Fire Fighter Fatality Investigation and Prevention Program within the NIOSH Division of Safety Research.

Andrea F. Wilkinson, MS, LAT, ATC is a Health Scientist in the NIOSH Firefighter Health Program within the NIOSH Division of Field Studies and Engineering.

Emily J. Haas, PhD, is the Associate Director for Science for the NIOSH Division of Safety Research.

Jay L Tarley, CFEI, is a Physical Scientist and Lead for the Post-Market PPE Testing Team in the NIOSH National Personal Protective Technology Laboratory.