A strong safety mindset supports aggressive interior operations only when warranted, and requires that firefighters base these decisions on a risk-benefit assessment. Equally as important, we must ensure continuous personnel monitoring and rehab whenever our crews are in high-heat or high-stress conditions. We need to support officers who request additional resources quickly and err on the side of frequent and appropriate rehab. Additionally, we must educate our officers about the correlation between PPE enhancements and heat-stress events.
By the Numbers
Heat-stress and heat-related cardiac events aren’t occurring because firefighters are less fit or less tough. We see more attention being given to firefighter fitness than at any point. A report by the Illinois Fire Service Institute (IFSI, 1998) references Smith et al. (1997), which documents a firefighters’ average heart rate when exerting themselves during overhaul in ordinary (ambient) room temperatures as 139 bpm vs. 175 bpm when exerting themselves during overhaul in live fire conditions. Additionally, Smith et al. (1995) documented an increase of 50 bpm in firefighters walking on a treadmill wearing PPE vs. street clothes. Further, the 1998 IFSI report suggests that firefighters lose nearly two quarts of sweat per hour when firefighting in newer PPE.
Firefighters are covered head to toe in PPE designed to keep heat away from the body. It’s difficult keeping heat away from the body while simultaneously allowing heat to escape. This is the dilemma of new gear. In 2007, NFPA 1971 raised the THL (total heat loss) requirements for manufacturers—a change that will improve new gear. Most firefighters work in gear designed before those changes took effect. Further, this design change will lessen—not eliminate—the problem.
The U.S. Fire Administration produced a manual on Emergency Incident Rehabilitation (February 2008), and NFPA 1584 addresses rehab for members during operations and training exercises. These documents are good resources for those seeking to implement rehab into their department SOPs. Neither identifies hard and fast rules, per se, relative to when and where rehab must be established. Instead, they state that the decisions should be based on scene conditions, environmental factors and the experience of the IC. But NFPA 1584 does establish guidelines to help an IC with this effort:
The company or crew must self-rehab (rest with hydration) for at least 10 minutes follow-ing the depletion of one 30-minute SCBA cylinder or after 20 minutes of intense work without wearing an SCBA. The company officer (CO) or crew leader must ensure that all assigned members are fit to return to duty before resuming operations.
The company or crew must enter a formal rehab area, drink appropriate fluids, be medically evaluated and rest for a minimum of 20 minutes after any of the following: depletion of two 30-minute SCBA cylinders; depletion of one 45- or 60-minute SCBA cylinder; whenever encapsulating chemical protective clothing is worn; and following 40 minutes of intense work without an SCBA.