Abstract:

In ordrer to solve the heavy stress caused by multilayer heavy firefighter's protective clothing, a cooling fire fighter protective clothing was developed using a liquid cooling device to alleviate the thermal response of firefighters. Thermal manikin was utilized to analyze the cooling performance of the cooling fire fighter protective clothing in a hazardous environment. The firemen working environment (temperature of 40℃ and relative humidity of 50% ) was simulated. The influence of different arrangement of the heat transfer network on the skin surface temperature of the thermal manikin, temperature under the heat exchange pipeline, the temperature of the heat exchange pipeline interval, and temperature difference for inlet and outlet of the cooling equipment was investigated. The results indicate that the cooling equipment efficiently reduces the skin surface temperature of the thermal manikin, and the cooling performance of different distributions of heat transfer pipeline is different. The skin surface temperature of the thermal manikin with the horizontal pipe arrangement is up to 0.58 ℃ higher than that with the longitudinal arrangement. Both under the pipeline and in the pipeline interval, the temperature difference of the horizontal pipe arrangement is always larger than that of the longitudinal arrangement.The temperature difference for outlet and inlet of the horizintal arrangement is up to 3.8℃, higher than the longitudinal arrangement. After 20min, the temperature difference is still higher than the longitudinal arrangement. The experiment indicated that the cooling fire fighter protective clothing using the horizontal pipe arrangement can alleviate heat stress. It also can prolong working time and improve the efficiency of firefighters’ rescue activities.

Key words: heat stress, firefighter's peotective clothing, cooliing device, skin surface temperature, heat exchange pipeline, temperature difference for outlet and inlet