Historically, firefighting has been a hazardous profession. In response to this, many departments and national organizations have adopted rehabilitation protocols to minimize excess risk to firefighters. Fire rehab is a coordinated plan to ensure firefighters, who encounter extremes of temperature, exposure, and exertion, do not develop significant illness related to exertion or exposure. Fire rehab can vary from simple temperature management and oral rehydration to aggressive medical treatments and transport to a higher level of care.
Fire rehab takes varied forms in different regions. Small, rural fire services may have few responders with medical training and coordinate with local EMS agencies to assist or oversee rehab, while some fire services have many trained EMS providers and coordinate their own rehab, including transport to health care facilities. Large services may have highly scalable rehab plans that include multiple rehabilitation units operating under a coordinating officer. Fire rehab is continually evolving as our understanding of physiologic responses to exertion and exposure change, technologies evolve, and risk tolerance adjusts.
In 1987, the National Fire Protection Association (NFPA) released its Standard on Fire Department Occupational Safety and Health Program, which addressed common dangers and protective measures for firefighters comprehensively. The U.S. Fire Administration (USFA) added to the literature on this topic in 1992 with the short report FA-114, Emergency Incident Rehabilitation, which included a sample standard operating procedure (SOP) for fire rehab. A textbook bearing the same title was released in 1997, further detailing the science and reasoning informing these protocols. USFA published an updated, and much more comprehensive, report on Emergency Incident Rehabilitation in 2008, which included an updated SOP. In the interim, NFPA 1584, Recommended Practice on the Rehabilitation of Members Operating at Incident Scene Operations and Training Exercises was issued in 2003, establishing guidelines for fire services. These recommendations were upgraded to standards in a 2008 update and again updated in 2015, with carbon monoxide monitoring added to recommended practices. This summary of fire rehab issues and procedures draws heavily from these essential sources.
It is worth noting out that fire rehabilitation, when discussed in the context of wildfires, relates to ecological recovery of an affected area, not physiological recovery of humans working to contain fires. This subject is addressed in other literature and will not be a topic in this article.
Most work-related injuries among firefighters are minor, with muscle pain, strains, or sprains accounting for 46% of fire ground injuries, followed by wounds, bleeding, or bruising, causing 14% of injuries. Smoke or gas inhalation accounted for 8% of fire ground injuries, and thermal stress or exposure (frostbite, heat exhaustion) caused 7% of injuries in 2016.
As firefighting became professionalized during the 1970s and 1980s, firefighter related deaths declined significantly. While the overall number of injuries among firefighters responding to incidents has decreased over the past 30 years, the number of fires has also declined; the overall rate of fire ground related injuries have been relatively stable during that time. The rate of firefighter deaths has been relatively stable as well, with a slight decrease in the past ten years.
Stress and overexertion, including myocardial infarction and cerebrovascular accidents related to duties, are the most common cause of firefighter deaths, accounting for 54.6% of all firefighter deaths over the past 10 years. Of the 16 deaths related to fire ground activities in 2016, seven (41%) were myocardial infarctions — nineteen of 21 (90%) deaths occurring shortly after fire ground activities related to myocardial infarction. While stress-related injuries are the most deadly, they also represent a small minority of injuries; just 2 percent of all firefighter injuries are stress related.
Indications for Fire Rehabilitation
Formal fire rehabilitation procedures are necessary for incidents requiring significant exertion or where there is a significant risk of injury, exposure, or stress. Most structure fires or wildland fires will need some type of rehab operations, but training exercises and large events requiring responses, or even standbys, may require rehab operations as well.
Establishing Fire Rehabilitation Operations
The scale and scope of fire rehabilitation operations will vary depending on the type and size of the incident. Rehab operations should have dedicated staff explicitly focused on rehab, without separate firefighting responsibilities. NPFA 1584 calls for a dedicated rehab manager, who ensures adequate food and hydration for responders, accountability of all personnel (with appropriate record keeping), and release of individuals needing additional medical care to EMS. While it may be necessary for resource-limited settings to have the same personnel provide both rehab oversight and transport for firefighters requiring a higher level of care, this can cause interruptions in care and documentation of rehab operations, so it is avoided in some services.
NFPA 1584 recommends that EMT-Basics, at a minimum, should be available for fire rehab. Rehab personnel should have access to at least basic first aid supplies, monitoring equipment, and an automated external defibrillator.
NFPA 1584 makes specific recommendations for the minimum frequency and duration of rehab:
These guidelines, based on the use of SCBA use, did not have their basis in the medically optimal duration of exertion, but rather convenience, as firefighters naturally keep track of time based on their use of SCBAs. Recent studies, however, typically study similar durations of exertion to observe the rehab time required for a return to physiologic baseline.
NFPA 1584 states that checking vital signs in rehab (temperature, heart rate, respiratory rate, blood pressure, oxygen saturation, and carboxyhemoglobin level in cases of possible smoke exposure) is necessary. Firefighters with a heart rate over 100 beats per minute or blood pressure over 160/100 mm Hg after 20 minutes of rehab should not return to activity, per NFPA 1584. There is little data on the implications of these cut-offs, but the most extensive retrospective study of these guidelines showed that about half of firefighters entered rehab with a heart rate over 100, while a small minority of firefighters fell outside recommended blood pressure parameters. Of note, only half of those entering rehab had a repeat set of vital signs checked.
A more controlled study of blood pressure during heavy exertion in a hot environment and subsequent rehab found that post-exercise hypotension is actually more common during rehab than significant and persistent hypertension.
Facilities used for fire rehab may vary by region, climate, type of incident, and length of response. Small, brief responses may require little more than rehydration available to firefighters. Larger incidents requiring more time will likely require establishing a formal rehab area close to the incident but separated sufficiently to be free of smoke, excess heat, or media covering the event. Some services have dedicated rehab vehicles, with fans, sun protection, and even active cooling measures, such as misters or proprietary devices that cool all or part of the body. Use of these devices has as its basis research demonstrating more effective cooling and tolerance of more extended periods of exertion in hot, humid conditions when employing active cooling measures, with forearm immersion in cool water providing more improvement than cool mist (although subsequent research has brought this conclusion into question).. Longer responses may require food provisions as well, which can be provided most easily with pre-packaged food but may include a larger scale food preparation.
The goals of fire rehabilitation are:
While this article will focus on dedicated fire rehabilitation areas, staff, and procedures, it is important to remember the importance of firefighters monitoring each other for concerning signs or symptoms requiring medical attention. Screening firefighters for medical concerns should not be limited to formal rehab operations.
Fire rehabilitation protocols focus on problems much more common in the fire ground than in other environments: heat exhaustion and stroke, dehydration, hypothermia, carbon monoxide poisoning, and cyanide poisoning. Given the danger of myocardial infarction, triage, treatment, and transport of firefighters with concerning symptoms will also receive coverage.
Firefighters face several risk factors for heat exhaustion and stroke. Exposure to very high temperatures near fires is an obvious risk factor, but the danger of hyperthermia from vigorous exertion and high environmental temperature and humidity far from a fire can also lead to deadly heat stroke. Temperatures can reach 1,500 degrees Fahrenheit during flash-overs or back drafts in structure fires, and chemical fires can reach even higher temperatures. Prolonged exposure to high outdoor temperatures, especially in full protective gear, can pose significant risks. Heat stroke has caused multiple deaths during training as well.
The U.S. Army has developed the acronym HEAT to outline risk factors for heat illness:
Heat exhaustion characteristically presents with fatigue, lightheadedness, weakness, or dizziness related to hyperthermia. Heat stroke is a more severe condition marked by severe neurological abnormalities, such as altered mental status, and more significant hyperthermia. While temperature measurements can be helpful in identifying heat-related illness in the field, temporal, tympanic, and oral temperature measurements can deviate from core temperature and mislead providers into a false sense of security. Firefighters at risk who exhibit symptoms of heat exhaustion or heat stroke should be cooled and transported regardless of field temperature measurements.
Numerous factors affect a firefighter’s risk of heat-related illness. Dehydration and salt depletion can significantly affect core temperature and response to heat. Excess body weight or poor conditioning can also make firefighters more susceptible to heat-related illness. Rashes, sunburns, and other skin conditions can affect the transfer of heat from the skin. Chronic illnesses, such as diabetes and CHF, and acute conditions, such as infections, which could cause a fever even preceding response to a fire, can increase a firefighter’s risk. Older age has also been shown to increase the risk of heat illness. Medications, such as antihistamines and tricyclic antidepressants (decreasing sweating), diuretics (causing dehydration and salt depletion), ephedrine and amphetamines (increasing heat production), and lithium (leading to water loss) can affect adaptation to hot conditions. Turnout gear interferes with the body’s ability to cool, so firefighters should remove protective clothing during rehab.
Heat exhaustion is closely related to dehydration, which can exacerbate heat illness. There is a large body of literature on the effects of dehydration on cognitive function, exercise tolerance, and heat tolerance. Recent research of firefighters presenting to training exercises has shown that hydration status (based on urine specific gravity) is often suboptimal (over half of study subjects were dehydrated) before even beginning firefighting activities. During simulated firefighting activities, a majority of firefighters lose over 1% of body weight in fluid loss - enough to affect mental function, strength, and dexterity. Of note, the triggering of thirst does not occur until fluid losses of 2% of body weight - which, due to decreased skin blood flow and sweating rates, can increase core body temperature by 0.2-0.4 degrees C. It is therefore necessary for firefighters to initiate rehydration before they develop thirst to prevent significant dehydration and heat exhaustion. Given that over a liter per hour of water is lost during exertion in hot environments, firefighters should drink at least 2 to 4 ounces of fluids after every 20 minutes of firefighting or training activities.
While the unique risks to firefighters most often involve exertional stress and heat-related injury, they may also undergo exposure to cold, damp, and freezing conditions, placing them at risk of chilblains, trench foot, frostbite, and hypothermia.
Accidental hypothermia is a drop in core body temperature below 35 degrees Celsius. Patients typically shiver when cold, down to a temperature of around 32 degrees Celsius, at which point shivering stops and patients typically develop altered mental status and J waves on EKG. Atrial fibrillation is also commonly found at this temperature. Unconsciousness usually accompanies a core temperature below 28 degrees. Care should be taken to move hypothermic patients gently as there are reports of patients developing ventricular arrhythmias with normal jostling movements while significantly hypothermic.
ACLS is the usual recommendation for patients with hypothermia and no palpable pulse. Ventricular arrhythmias may be refractory to defibrillation in hypothermic patients, although this is somewhat controversial. An initial attempt at defibrillation is the recommended course in hypothermic patients with shockable rhythms. Use of vasopressors during resuscitation of the hemodynamically unstable hypothermic patient is controversial but recommended in AHA guidelines.
Rewarming is the cornerstone of treatment for accidental hypothermia; this can involve active external rewarming, infusion of warmed saline, forced air rewarming for ventilated patients, gastric and bladder lavage, peritoneal lavage, thoracic lavage, endovascular rewarming, ECMO, or cardiac bypass. Aggressive rewarming of a significantly hypothermic patient requires transport for aggressive and invasive measures.
Carbon Monoxide Poisoning
While high temperatures and oxygen deprivation pose significant risks to firefighters, high carbon monoxide levels are the most imminent threat to life in structure fires. Symptoms of carbon monoxide toxicity include headache, dizziness, nausea, confusion, altered mental status, and shortness of breath. NFPA guidelines state, “Any firefighter exposed to CO or presenting with headache, nausea, shortness of breath, or gastrointestinal symptoms at an incident where CO is present should be assessed for carbon monoxide poisoning.”
Treatment for carbon monoxide poisoning primarily consists of 100% oxygen. Studies of hyperbaric oxygen treatment have produced variable results.
Multiple other toxins are present at sites of structure fires, including acrolein, formaldehyde, glutaraldehyde, and hydrogen cyanide, and these gases are often present at dangerous levels even after the fire appears to have burned out, during “knock down” operations. Loss of consciousness in a fire is suggestive of significant inhalational injury.
Firefighters have a disproportionately high rate of workplace-related myocardial events, with 45% of firefighter deaths while on duty attributed to cardiovascular events vs. 15% of all deaths that occur at work. Fire suppression activities appear to carry exceptionally high risks. While only 1% to 5% of firefighters’ time is spent actively fighting fires, 32% of cardiovascular deaths among firefighters occur during active fire suppression. The odds of dying are higher while performing any emergency duties although the highest risk activity is fire suppression. Physical training is also a relatively high-risk activity for firefighters.
Cardiovascular events among firefighters share the same risk factors as events among the general population. Firefighters who die from cardiovascular events are older, more likely to smoke, have more cardiovascular risk factors, and are more likely to have known coronary heart disease than other firefighters. Of note, most U.S. firefighters who died of cardiovascular events between 1996 and 2002 had not undergone a fire department medical examination in the two years before their deaths.
Researchers have proposed multiple explanations for the increased risk of cardiovascular events among active firefighters. Oxygen depletion, carbon monoxide toxicity, physical exertion, and emotional stress all likely play a role in the risk of MI.
Diagnosis of myocardial infarction can be complicated in the field as many firefighters actively involved in fire suppression have EKG changes suggestive of ischemia. There are also many potential causes of chest pain during fire suppression activities, including musculoskeletal pain and inhalation injury. A firefighter with anginal symptoms, however, should be treated according to local EMS protocols for a suspected cardiac event and transported to an Emergency Department for further evaluation.
Given that most cardiovascular events among firefighters occur in people with modifiable risk factors, and repeat physical examination and testing after an initial evaluation of new hires is not yet the norm among fire departments, there appears to be an opportunity to improve firefighter safety with improvements in screening and treatment of cardiovascular risk factors.