Reflections on Wildland Firefighting
Protective Clothing, Equipment, Hazards, and Procedures
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For two summers in the 1960s I fought wildland fires as a member of a crew, first with the State of Oregon Forestry Department and then with the East Lane Fire Protection Association. Later, I spent a summer in Washington state as a “smokejumper” who parachuted into areas near small fires and contained them before they spread. Although wildland firefighting today is quite different than it was in the 1960s and 1970s, my experiences provide insight into the many industrial hygiene concerns associated with this work, including the protective clothing worn by wildland firefighters and why it differs from that worn for structural firefighting.
FIRE CREW TRAINING Part of the training given to my crews was how to “line” a fire—that is, deprive it of fuel through digging and the removal of vegetation. The tools we used were a shovel; a heavy-duty hoe known as a hazel hoe; a grub hoe; a Pulaski, which has a wooden handle and a head that combines an axe and an adze; and a regular axe. Some crew members also had chainsaws. The Oregon State Forestry crew did not use water to line fires; the East Lane crew had a water tanker available. But both crews learned how to dig a trail around a fire to stop it from spreading without water.
First, axes and chainsaws were used to clear the area of heavy brush. Crew members with Pulaskis would follow, cutting roots and heavy vegetation, and then others with hazel hoes would clear a trail three feet wide of everything that could burn. Those of us with hazel hoes would spread out by several feet, clear a short section, then move along the line. We were taught to grab the hazel hoe with one hand close to the head and the other hand lower down, with the handle projecting between our legs. This allowed precise movements into the earth to make a trench or scrape and remove the dirt (on hillsides, trenching was necessary to prevent rolling embers from going over the trail). Shovels brought up the rear to ensure the removal of all burnable materials. In this manner we would surround the fire with a three-foot-wide trail cleared of fuel.
The author, John C. Ratliff, as a smokejumper at the North Cascades Smokejumper Base in Winthrop, Washington, 1972. Photo by Larry Longley.
The clothing we used on these crews consisted of cotton underwear; a cotton shirt; long, black jeans; leather gloves; a large bandana around our neck, which we could pull up over our mouth and nose; and leather boots with heavy socks underneath. Hardhats were mandatory and protected us from falling limbs or debris. The pants were “stagged,” or cut off the cuff, to prevent broken branches from becoming stuck in the cloth and tripping us. Each of us also carried a canteen, as it was extremely important to drink when fighting wildfires.
SMOKEJUMPING In 1972 I became a smokejumper out of the North Cascades Smokejumper Base in Winthrop, Washington. Smokejumpers were deployed to small fires, usually caused by lightning strikes, that typically affected only a single tree. At that time, these fires did not spread quickly, and a crew of only two smokejumpers could extinguish them. Smokejumpers wore a jump suit, which was very heavy and had pockets equipped with 200 feet of “letdown tape” that allowed the smokejumper to rappel out of a tree if the parachute got hung up. The suit was equipped with a sewn-in nylon line that protected the smokejumper from groin injuries caused by landing in trees. Smokejumpers also had a reserve parachute with a knife on top for cutting things after landing or disentangling suspension lines following exit from the aircraft. A helmet with a wire mask kept limbs and branches from striking the face.
The protective clothing smokejumpers wore underneath the jumpsuit was similar to what firefighting crews wore, except that smokejumpers had fire shirts, and their boots were made of much thicker leather. Drinking water was dropped to us as part of our firefighting kit, which included a chainsaw for cutting down burning trees. Two-person smokejumper crews had a radio for contacting the aircraft overhead (and our headquarters if we were close enough).
Smokejumper training included a basic fire behavior school. We learned about the “fire triangle”­—its need for fuel, oxygen, and heat; how heat is transferred via conduction, convection, and radiation; and how fuel, weather, and topography influence the spread of fire. We learned that fuel in a forest had a heat ignition temperature of approximately 560 F. Heat transfer happened due to conduction, convection, and radiation, and fires spread due to fuel, weather, and topography. We were given the following instructions: 1. Keep informed about fire weather conditions and forecasts. 2. Know what your fire is doing at all times. Observe personally and use scouts. 3. Base all actions on the current and expected behavior of the fire. 4. Have escape routes for everyone and make them known. 5. Post a lookout when there is possible danger. 6. Be alert, keep calm, think clearly, and act decisively. 7. Maintain prompt communications with your team, your boss, and adjoining forces. 8. Give clear instructions and be sure they are understood. 9. Maintain control of your team at all times. 10. Fight the fire aggressively but provide for safety first.
We also learned about “bummer indicators”—that is, situations in which firefighters need to re-evaluate conditions and consider evacuating the area or deploying their fire shelter. One bummer indicator was building a fire line downhill toward a fire, because fires burn very fast uphill. (Later, I investigated a fatal incident where loggers working uphill from a fire were overtaken.) Other bummers were a change in wind direction, a feeling that the weather was getting hotter and drier, and areas to avoid if possible: hillsides, where debris from a rolling fire could fall and ignite; difficult terrain that slowed travel; and heavy forest with unburned fuel between you and the fire. Being in country you hadn’t seen in the daylight was another bummer.
WILDLAND FIREFIGHTING TACTICS Today, climate change has significantly altered wildland firefighting. Forests are drier, fires are hotter, and a lightning strike can easily lead to acres of fire in a matter of hours. In most situations, two-person teams of smokejumpers are no longer adequate for a lightning strike, especially if the fire, once spotted, is simply watched for a day or two. An entire crew may be needed to handle lightning strikes. It used to be rare for downed electrical lines to start fires; recently, these fires have quickly burned extensive acreage, necessitating more crews than in the past. Sometimes, municipal crews arrive in their fire trucks and their turnouts to fight wildland fires.
Top: The aftermath of a wildfire that swept through a logging site. Photo by John C. Ratliff.
Bottom: A wildfire from the 1980s in Oregon. Photo by John C. Ratliff.
These changes have led to recent reevaluations of both protective clothing and procedures for wildland firefighting. Crew compositions have also changed, with women taking an ever-larger role. Recent research has examined the use of medication by wildland firefighters, specifically glutamine supplementation to reduce damage to their gastrointestinal tract, subjective fatigue level, and perceived exertion.
The types of fires we see now, with the crowning and extremely fast movement of the fire at the head, pose extreme hazards. Before fires behave like this, crews need to be pulled from the fire lines and attacks made by other means, such as air tankers.
Recent articles in Smokejumper magazine describe changes in tactics that illustrate difficult tradeoffs. One author suggests that the U.S. Forest Service has prohibited nighttime firefighting for safety reasons, even though it is well known among wildland firefighters that fires “lay down” at night, when weather conditions change and winds abate. Another article published in January 2022 describes the refusal by fire mangers to let smokejumpers attack a small fire; when the fire got out of control, huge numbers of firefighters were needed:
Now we have numerous wildfires burning that could have been put out earlier by quick initial attack with a small number of resources. As in the Tamarack Fire, a single tree turns into a multi-million-dollar event and safety is used as a reason for not putting it out in its early stages. Four jumpers could have handled the single, lightning-struck tree on July 4. Now there are over 1,000 firefighters involved with additional aircraft daily. What situation is safer for firefighters—four smokejumpers, a walk-in hand crew of ten dealing with a single tree, or over 1,000 firefighters handling a 50,000-acre fire?
There are times when firefighters are trapped and must resort to sheltering. The U.S. Forest Service requires wildland firefighters to carry specialized shelters made of aluminum and fiberglass that provide protection in temperatures above 1,000 F. Specialized training is necessary on how to climb in and seal the shelter, and how to breathe effectively (firefighters are instructed to keep their heads four inches above the ground inside the shelter).
But shelters don’t guarantee survival. In the 1994 Glenwood Springs, Colorado fire, 12 smokejumpers and wildland firefighters were lost despite the use of shelters.
IH CONCERNS In all wildfire situations, the IH stressors are multiple. These include hard, hot work, exhaustion, long hours, and the difficulty of staying hydrated. Heat exhaustion and heat stroke are possible, and burns are a constant hazard. Because of the physical demands of fighting wildfires, the crews I served on didn’t use the turnout clothing worn by structural firefighters. Occasionally we worked extended times without a break. Smokejumpers had much more leeway and took breaks when needed.
Some of the concerns about occupational diseases among wildland firefighters involve inhalation of chemical contaminants such as carbon monoxide and particulate matter (PM2.5) in smoke. According to a 2011 paper in the Journal of Occupational and Environmental Hygiene, if data from prescribed burns are correct, most wildland firefighters will not be overexposed to PM2.5.
The toll of COVID-19 on wildland firefighters has not been widely reported. An article in the July 2022 issue of Smokejumper identifies COVID-19 as the leading cause of death on wildland fires in 2021.
A 2019 study in the International Journal of Occupational Medicine and Environmental Health reported that respirator use was found to reduce the decline in lung function among wildland firefighters. But other factors may complicate the decision to recommend respiratory protection for wildland firefighting, such as their inhibitory effects on verbal communication.
In 2020, the National Academies of Sciences, Engineering, and Medicine held a workshop on the effects of wildland fire emissions on air quality and human health. As described in a report on the workshop, one presenter discussed the complex exposures today’s firefighters experience at the fire line. These exposures vary according to the task the firefighters are engaged in, the type of vegetation, and other sources of air pollutants. According to the report, exposure assessments for wildland firefighters have typically relied on PM measurements, but “the relationship between PM and other toxics in wildfire smoke may vary across fires, and it is unclear whether PM is the best measure to use for all health outcomes.” Carbon dioxide levels and urinary biomarkers such as metabolites, PAHs, and methoxyphenols have been suggested as alternatives to PM, but all have limitations.
The report also discusses the adverse health effects of smoke exposure for firefighters such as oxidative stress, inflammation, and decline in lung function. Associations exist between career length and hypertension and increased risks of lung cancer and cardiovascular disease. The report calls for more research into exposure pathways and development of new respiratory protection: “Currently, there is no commercially available respirator that meets necessary requirements for flame resistance, clean air delivery over extended periods of time, and portability,” the report reads.
At the workshop, Tim Reinhardt, CIH, presented more information concerning respirators and the particulate hazards wildland firefighters face. During construction of fire lines and other tasks such as mop up, the respirable particulates include crystalline silica from the soil. Wildfire smoke contains carbon monoxide and formaldehyde; as the CO concentration increases, so too does the formaldehyde concentration. Reinhardt characterized the permissible exposure limit for nuisance respirable dust of 5 mg/m3 as unacceptable for wildfire smoke particulate matter, and he argued that exposure limits must consider the specific toxicity and carcinogenicity of wildfire smoke, as well as the PELs for other respirable hazards that may be present in the wildfire environment—including crystalline silica at 0.05 mg/m3. An organic/elemental carbon-based PEL for wildfire smoke is needed, Reinhardt said.
PREVENTING EXPOSURES This article just touches the surface of industrial hygiene concerns for wildland firefighters. But I hope it spurs interest in the subject and allows for more discussion of how IHs can help prevent wildland firefighters’ exposures to both physical and health hazards that may become life threatening.
JOHN C. RATLIFF, CSP (Retired), CIH (2006–2017), MSPH, retired from active practice in 2014.
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International Journal of Occupational Medicine and Environmental Health: “A Systematic Review of Health Impacts of Occupational Exposure to Wildling Fires” (February 2019).
Journal of Occupational and Environmental Medicine: “The Effect of Acute Glutamine Supplementation on Markers of Inflammation and Fatigue During Consecutive Days of Simulated Wildland Firefighting” (February 2019).
Journal of Occupational and Environmental Hygiene: “Personal PM2.5 Exposure Among Wildland Firefighters Working at Prescribed Forest Burns in Southeastern United States” (August 2011).
National Academies of Sciences, Engineering, and Medicine: “Priorities to Address Smoke Hazards for Wildland Firefighters,” Wildland Fires: Towards Improved Understanding and Forecasting of Air Quality Impacts—A Workshop (PDF, presentation by Tim Reinhardt, September 2020).
National Academies of Sciences, Engineering, and Medicine: “Wildland Fires: Toward Improved Understanding and Forecasting of Air Quality Impacts” (2022).
The New York Times: “Elite Crew Mourns Deaths of 12 in a Wildfire Blast in Colorado” (July 1994).
Political Geography: “Negotiating Adversity with Humour: A Case Study of Wildland Firefighter Women” (January 2019).
Smokejumper: “A View of the Largest Wildfire in the History of New Mexico” (October 2022).
Smokejumper: “The Safety Card” (PDF, January 2022).
University of Nevada: “Sisters in the Brotherhood: Experiences and Strategies of Women Wildland Firefighters” (May 2019).
U.S. Army: “DEVCOM Soldier Center Designs Protective Jumpsuit for Elite Firefighters” (May 2022).