Based On The Design Of Fire Service With Liquid Cooling Active Cooling Effect

As the major force of fire-rescuing activities,firefighters make their best contribution to firefighting.In common instances,firefighters need not only fight with the fires but also with the emergency responses.The working is characterized by high-intensity load,resulting in the increase fire crew’s risk of physical and mental illness.With the perfection of the social security system,a lot of guarantees are carried out to protective the security and health of firefighters by nations.This paper investigated the firefighting protective clothing which is essential to keep firefighters working in the fire security.Wearing firefighting protective clothing shielded flames,radioactive,conductive heat and hazardous chemical substances protects individual life.The firefighting protective clothing worn by firefighters is typically heavy,thick with multiple layers.The reduced water-vapor permeability across the clothing layers also limits the rate of evaporative heat loss with increasing the metabolic load.Thus,the effects of high surrounding temperature and metabolic load accumulate heat leading to the physiological responses associated with exacerbating the strain of thermoregulation system and uncontrolled heat balance.Eventually,although firefighting suit can be protected firemen from burning,it placed the firefighters under heat strain,causing responses such as dizziness,spilt,increased core temperature and lost concentration.The effectiveness of rescue agents and security of firefighters may be influenced in heat strain.Therefore,the design of firefighting protective clothing needs to combine ergonomic and comfort in addition to thermal protection.The aim of paper is to alleviate heat stress and prolong firemen’s working time during wearing firefighting protective clothing.Firstly,a method is chosen to reduce heat strain.In order to meet the demands of firefighting activities,liquid cooling strategies which own the advantages of dissipating excess heat by conduction,the lower weight and volume are used in the firefighting protective clothing.In the study interval of heat exchange tube can be explored which is the key factor of liquid cooling equipment,the discussing the relationship between the interval of heat exchange tube and cooling effect during high condition.The conclusion is conducted to provide a reference for the higher cooling effect under different conditions.Secondly,this study designs cooling-firefighting garments with different arrangements of heat exchange tube according to situation of the heat invaded.With the characteristic and cooling capacity of cooling-firefighting garments is tested by using thermal manikin "Walter" and analyze the wearing comfort.The paper measured the thermal resistance,moisture vapor resistance,temperature under the heat exchange pipeline,the temperature of the heat exchange pipeline interval,temperature difference for inlet and outlet of the cooling equipment and skin temperature of "Walter".The experimental results are analyzed that the cooling-firefighting protective clothing which it used the horizontal pipe arrangement can alleviate more heat stress and prolong work time.There are more than 60min for keeping skin temperature below 36 ℃ than only wearing fire-fighting protective clothing.It shows that the working time is prolonged and the firemen’s life can be keep safety.Finally,analysis of the subjective experiment through wearer trials was conducted.The result shows that the working time can be prolonged by the cooling-firefighting clothing obviously.The thermal senses and wearing comfort of the horizontal one is better than the longitudinal one.And the cooling-firefighting clothing prolonged continuous work(up to 20min)in heat stress conditions.The results are in compliance with the objective evaluation.It proves that cooling fire-fighting protective clothing can provide better cooling performance and longer working time.