Shifts are long, often in steep terrain and at higher elevations.
The weather is usually hot and dry, and the fire increases exposure to heat. This brochure focuses on the risks of heat stress, and what the firefighter should do to minimize those risks. When hard work is performed in a hot environment, blood is sent to the skin to cool the body, primarily through evaporation of sweat. As sweating continues, often at a rate of more than 1 liter per hour, the body loses lots of fluid. That can compromise heart and circulatory function and the ability to work.