There are many risks for respiratory exposure while working at a residential structure fire. The most obvious threat is within the burning structure, which is why the fire service has expectations of SCBA usage for work in this location. However, risks are also present on the fireground outside of the structure and potentially from PPE after the firefight has ended, and too often we have failed to adequately protect firefighters when they are not in an immediately dangerous to life and health (IDLH) environment. Some major findings from our study include:

Fortunately, respiratory protection control measures are well known and in place in many fire departments. Positive-pressure self-contained breathing apparatus (SCBA) can essentially eliminate inhalation of these toxicants (Occupational Safety and Health Administration, 2011). Unfortunately, however, firefighters do not always wear SCBA, for example, when sizing up the fire, when working as the engineer or incident commander, or when conducting overhaul operations. Results of this study highlight the need for SCBA protection throughout the firefight as well as the importance of enforcing these policies during overhaul and outside vent operations. Furthermore, pump operators and incident commanders should consider respiratory protection when working in smoky conditions or when they may be exposed to diesel exhaust.

Additionally, secondary exposure to off-gassing may be reduced by allowing the PPE to air out outside of enclosures. The off-gas levels returned to near background concentrations after 17–36 minutes after our initial measurements for the majority of the volatile organic compounds (VOCs) (Fent et al., 2017). However, semi-volatile compounds would likely take much longer to volatilize and is an area of continuing research.

While protecting the airway may be the most important control measure to implement on the fireground, it has become increasingly apparent that dermal absorption plays a key role in systemic exposure for firefighters. Skin exposure can occur during fire fighting by way of permeation or penetration of contaminants through the hood, turnout jacket and trousers, in between interface regions of this ensemble, or through the cross-transfer of contaminants on gear to skin.

Current PPE designs have important, yet limited ability to fully protect against fireground products of combustion reaching the skin. Research and development activities are currently taking place to redesign PPE to further reduce chemical ingress through particle blocking hoods and tightening down PPE interfaces. The benefit of the changes still must be quantified. It is also important to study opportunities to implement administrative controls to reduce these absorption risks. By managing these administrative controls, the fire service may be able to affect a reduction in exposure even using current PPE.

Fire fighting increases thermal and cardiovascular strain. In fact, the increase in body temperature exacerbates the increase in cardiovascular strain. We have documented significant increases in heart rate (near age-predicted maximum for fire attack, search, overhaul, and outside vent job assignment) and core temperature (mean increases of 1.8 F for fire attack and search and ~3.1 F for overhaul and outside vent activities) even during this short experiment in which firefighters worked with a 30 minute SCBA air cylinder.

Additionally, firefighters were assigned to unique responsibilities, (i.e. overhaul was done by a different crew than fire attack) such that each firefighter was fresh prior to their job assignment and core temperatures could increase to even higher levels if multiple bouts of activity are required. Furthermore, earlier studies that have shown convincingly that some of the cardiovascular changes, such as increased coagulatory markers or a decrease on cardiac blood flow could be mechanistically linked to sudden cardiac events. In this study, we found that five firefighters who had normal ECGs in a 12-hour control period developed indicators of myocardial ischemia following fire fighting (Smith et al., 2019b).

Medical evaluations performed by a physician serve as the most important steps to ensure firefighters can endure the cardiovascular and thermal strains of the job. Those tests must be performed by a physician who understands the job’s physiological and psychological stresses. Firefighters also need access to a wellness and fitness program to ensure they are fit enough to safely do the job.

On scene, leaders should consider the physical stress of the job and consider rotating crews or providing relief when possible. This may include having a fresh group of firefighters perform overhaul or repack the hosebed. In places where personnel are severely limited, it may mean having extended rehab time before performing overhaul, or even putting firefighters in lighter-weight protective clothing to perform overhaul.

One of the great balancing acts that leaders face is providing adequate protection against burn injuries and smoke exposure on one hand, and the increased cardiovascular and thermal strain that comes from using heavy, encapsulating gear on the other hand. Rehabilitation also provides an opportunity to make sure that firefighters are evaluated to make sure they are recovering as expected.

Many fire departments have policies for wearing SCBA during fire fighting operations, and it is a common expectation during interior fire fighting activities. However, more widespread challenges remain when firefighters are operating in other job assignments. In recent years, anecdotal evidence suggests an increase in SCBA usage during overhaul. While this decreases exposure risks, this use comes with a cost, namely, an increase in the metabolic cost of the work and a resulting increase in temperature and cardiovascular strain. Fireground leaders should account for the increased metabolic work necessary when conducting overhaul with SCBA compared with the same task without an SCBA. In the Fireground study, we measured a mean increase in core temperature of ~3 °F while working through a single 30-minute SCBA cylinder in overhaul (Horn et al., 2018). Such an increase in core temperature may not be overly concerning for a rested firefighter. However, if that firefighter had just completed fire attack or outside vent, their core temperatures would already be elevated, and this additional work may result in core temperatures that increase to dangerous levels. To support extended use of SCBA throughout overhaul, leadership should consider bringing additional personnel to the scene in order to reduce the thermal and cardiac strain on firefighters. Additional personnel on scene will allow fire attack firefighters (who may be heavily exposed to fireground contaminants) to more rapidly conduct decontamination/rehabilitation. Another approach that has been implemented in some jurisdictions is to conduct overhaul after rehabilitation in lighter weight wildland/hybrid PPE in an attempt to mitigate the thermal and cardiovascular exposure risks while providing the highest level of airway protection.

Enforcing airway protection for other job assignments will, in many places, require a change in culture and expectations. Outside vent firefighters will often wear SCBA when in heavy smoke, but gasses such as HCN may not be visible and may partition to upper levels differently than heavier products of combustion such as particulate and benzene. Additionally, while it is good practice to establish command and pump operations at locations upwind from the smoke plume, such locations are not always available. In such cases, airway protection can provide an increase in contamination control (Burgess et al., 2020) if policies and procedures are implemented to support this control measure. While these fireground concentrations are found to be much lower than inside the structure, they are an increase over background levels and another source of exposure near the fire building.

Relatively recent understanding of risks posed by PPE off gassing after the firefight has led to some changes in policy and in some cases updates in apparatus and station design. But in its simplest case, because of the potential off-gassing route of exposure, turnout gear should be left outdoors to off-gas and/or separated and isolated from occupied compartments of an apparatus (e.g. bagged and/or transported in an unoccupied compartment on the apparatus or other vehicle). Some departments have assigned gear transfer totes to their members to reduce this risk in personal and fire department vehicles.

The Fireground study provided the first quantification of the effectiveness of gross on-scene decontamination techniques (Fent et al., 2017). While the evidence of effectiveness is clear, implementation of the practice has sometimes been met with challenges, resistance, and questions. Some of this resistance may be attributed to varying beliefs and behaviors related to wet decontamination techniques, such as concerns over time limitations and the safety impacts of wet gear (Harrison et al., 2018a). Such barriers to implementing post fire decontamination may be overcome through targeted messaging (Harrison et al., 2018b); but can also be reduced through managing iterative enhancements in processes as this relatively new fireground function is tested, evaluated, and improved.

As with any fireground function, training is important to learn technique. It is suggested that, if adopted at a fire department, wet soap decontamination be included during live-fire training evolutions so it can be more efficiently and effectively implemented on the fireground. This practice will help firefighters know how to best apply water to minimize soaking the gear and the firefighter. Water application will depend on contamination level but should mostly be used to pre-wet the gear, then rinse off the soap solution. Anecdotally, excessive water has been used to remove large pieces of debris from the turnout gear, which can result in soaking the gear and increase possibility for wetting interfaces and skin. Consider balancing wet and dry methods when large pieces of debris are present. However, if dry methods are used, it is important to manage the potential exposures from contamination that becomes airborne. Those being deconned as well as those doing the decontamination, and anyone downwind of that location, should consider appropriate PPE from this airborne particulate.

Fireground officers will also need to manage the process of handling PPE after it is deconned on scene, particularly if it is wet. The 2020 Edition of the NFPA 1851 standard (National Fire Protection Association, 2020) contains a decision support tool that should be consulted. In addition, fire departments should consider department policies for handling gear wetted by environmental conditions or hose overspray and enforce similar precautions that would be taken if the outer shell has been wetted these sources.

Environmental extremes can present important challenges while conducting fireground decontamination, and leaders need to make appropriate decisions to balance the risks from contaminated gear with other environmental hazards. It is important to remember that on a hot summer day the firefighter inside their PPE waiting to be deconned may have just completed a long, intense bout (or bouts) of fire fighting activity and cannot cool down or recover from the thermal and cardiovascular stress of fire fighting as easily as if his or her PPE were removed. Similarly, a firefighter conducting decontamination in freezing conditions may be at increased risk for hypothermia and frostbite. Thus, it is important to balance the risk of heat stress or cold stress for the member with the risk for additional chemical exposure. One way to manage this balance is to address environmental stressors as part of integrated rehabilitation. The flow of personnel through decontamination should be managed by prioritizing firefighters based on availability of air and their physical and psychological stress levels. Establish multiple decontamination lines/stations to move firefighters through more rapidly when feasible. Provide hydration where feasible. In the cold, manage cold stress by provide warming stations for all those being decontaminated and those working in decontamination lines as quickly as possible. Manage risk for slips and falls by making ice melt available where decontamination is taking place. Deconning fire fighting PPE is an important risk reduction process but should be managed with the other risks that may be present on each fireground.

Leadership in the fire service should also consider implementing a skin cleansing program for every response or training scenario where products of combustion are present. By including skin cleaning as part of training, firefighters can develop the expectation that they are responsible for cleaning themselves after a bout of fire fighting activity. Similar to decontaminating PPE after training, this process can begin to build muscle memory in controlled conditions prior to deployment on the fireground. Wipes can be made available as soon as firefighters exit a burn structure and begin debrief as well as during bottle changes, air fill stations, and before getting back on the apparatus. Making the wipes visible and company/command officers reminding firefighters to use them will reinforce this habit.

On the fireground, wipes should be made available near the command vehicle, staging areas, on forward located apparatus, and transition to rehabilitation. It may also be useful to provide a mirror at a few locations to help firefighters self-identify the presence of contamination. A small investment can go a long way in assisting firefighters to be efficient in their use of wipes and to be cognizant of the need to do so. Fireground leadership can support this awareness and implementation in best practices.

Implementing contaminated doffing techniques on the fireground may appear a foreign and challenging proposition in many departments. While a great deal of time and effort has historically been spent teaching firefighters to quickly and effectively don their turnout gear, relatively little time is typically spent on the doffing process. On the other hand, training for medical responses (EMS) will often focus on donning PPE appropriately for body substance isolation, but also highlights the importance of doffing PPE, particularly gloves, appropriately. Likewise, hazmat responses require specialized PPE and a controlled and institutionalized decontamination and doffing process to ensure these hazardous materials are not transferred to the responder. Thus, many firefighters are familiar with the need for contaminated doffing methods, and the fire service has adopted these processes for specific responses.

Now is the time for leadership to consider implementing similar approaches for contaminated equipment doffing after fireground activities. An opportune time to develop, test, and implement these techniques is during training scenarios, either live-fire training at an academy or station-based training. The more these approaches are practiced, the more likely they will be performed correctly on the fireground.

Incident scene rehabilitation has evolved in the fire service and has become a common fireground activity in many departments. Thanks in part to the evolution of NFPA 1584, processes have become standardized and expected. With the increasing concerns related to firefighter hygiene and cleanliness, there is an opportunity to evolve rehabilitation to integrate decontamination – from hygiene to hydration. In this way, the on-scene decontamination, contaminated doffing, and skin cleaning processes become part of an established fireground tactic.

It is important that these hygiene steps take place prior to entering rehab where feasible. If contaminated gear is not cleaned and doffed, then contamination can easily spread to firefighters’ skin as well as the equipment and personnel working in the rehab sector and then other firefighters. The potential for PPE off-gassing can further expose firefighters and support personnel as airway protection is not commonly worn in rehabilitation. Additionally, if hygiene practices are not appropriately managed, risk for ingestion of fireground contaminants can increase while eating finger foods where transfer from hand-to-food-to-mouth is possible. To reduce this risk, skin cleaning wipes or sinks can be provided along with mirrors at the entry to rehab as a reminder to clean skin in order to reduce risk to the firefighter and rehab personnel.

Finally, rehab provides an important opportunity to reflect on the incident actions as an individual and group. This process is important for tactical debriefing, but also to immediately report exposures from the incident and assess if personnel are recovering appropriately. Exposure tracking—both chemical and emotional—has become an important component of a firefighter’s personal activities after a fire. Several apps, such as National Fire Operations Reporting System (NFORS), have been developed to ease the reporting process. Leaders should consider encouraging personal responsibility in collecting this information, particularly during the initial recovery period allowed by incident scene rehabilitation. Furthermore, the time spent in rehabilitation can be used to ensure firefighters are appropriately recovering from the event. Those managing rehabilitation should be made aware of a firefighter not feeling well after strenuous activity in order to keep a close eye on the individual, in rehabilitation and after return to the station. Similarly, conversations within rehabilitattion may provide the opportunity to identify personnel who are emotionally struggling with the events of the incident so that peers may be able to provide support and assistance.