A recent report by the National Critical Care and Trauma Response Centre examined firefighter cooling in tropical field conditions. This of course is of particular concern for the health, safety and survival of firefighters who operate in climates that are affected by high environmental heat either year round or seasonally.
The authors of the report looked at both the physiological and perceptual responses of firefighters to protracted simulated incidents in tropical conditions and evaluated the effectiveness of four cooling methods to be incorporated into scene rehabilitation procedures.
They reviewed 60 firefighters who were observed operating in a protracted incident that included salvage operations, on-air SCBA utilization and hazmat containment in full NFPA compliant structural turnout gear. Operations consisted of three 30-minute periods, each followed by a 30-minute period of cooling including removal of their firefighting gear.
The firefighters were assigned to four separate cooling methodologies and paired by comparable body mass index (BMI). The four separate methodologies included:
- Resting quietly in the shade
- Ingesting 7.5 ML/kg of body mass crushed ice
- Immersion in 25 degree C water
- Sitting in front of a misting fan
All four groups had access to water and/or a carbohydrate/electrolyte beverage. The researches monitored core temperature throughout by an ingestible telemetry pill as well as tympanic temperature, heart rate, blood pressure and thermal discomfort ratings.
The investigators concluded that firefighting activities in protective firefighting apparel in a tropical environment promotes rapid heat storage. They determined that tepid water immersion is more effective in lowering core temperature than shade, crushed ice ingestion or use of a misting fan during rest periods.
They also concluded that for protracted incidents in such environmental temperatures, rehab with medical support should not only consist of hydration and cooling but should also be inclusive of temperate water immersion.
While this is a relatively small study of only 60 firefighters, certainly it is intuitive that tropical conditions add to heat absorption. Therefore, fire service leaders should work closely with medical clinicians to ensure environment-appropriate rehabilitation processes and procedures are in place.
These obviously may be geographically centered, having different procedures and protocols based on seasonal environmental challenges. Use this opportunity to review for your personnel the most appropriate rehabilitative processes.
Todd LeDuc, MS, CFO, CEM, MIFireE, is an assistant fire chief for Broward County (Fla.) Sheriff Fire Rescue. He’s also a director at large for the Safety, Health and Survival Section and a member of the IAFC On Scene editorial advisory board.