Fire fighting and its influence on the body

Working conditions for fire fighters can be described according to the environment temperature and the incident radiant heat flux. Measurements for this study in buildings for fire fighting training have shown that fire fighters are typically exposed to radiant heat fluxes of between 5 and 10 kWm(-2) during this kind of exercise. The heat load can nevertheless be much higher. In one case, 42 kWm(-2) was measured. The temperatures reached between 100 and 190degreesC at 1 m above ground, going up to 278degreesC in one case. Human trials have been performed with 17 fire fighters. After exercises (about 15 min) in a heated room, the mean core temperature of the fire fighters rose by 0.6degreesC with a surrounding temperature of 31degreesC and 1.0degreesC with 38degreesC. The sweat production varied from 0.7 to 2.1 lh(-1); 16% to 45% of sweat remained in the clothing layers. During the exercises in the training buildings, a mean of 48degreesC has been measured between fire fighters' clothing and workwear. These conditions lead to an increase of the relative humidity in all the jackets up to 100%. When the fire fighters came out of the fire, the humidity remained at this level in the PVC coated jackets while it was in some cases strongly reduced in breathable jackets.