Study On The Influence Of Personal Protective Clothing On Human Thermal Physiological And Psychological Response In Hot Environment

With the continual improvement in China's industrial intensity-,the exacerbating frequency and severity of fire accidents have increased.In Order to improve the professional quality of firefighters,the frequency and difficulty of fire training activities are also increasing.In training activities,the heat stress brought try high temperature environment and protective clothing can damage che physical and psychological health of firefighters.Protective clothing is.the most basic rescue equipment for firefighters,Since It is characterized with good thermal insulation performance,it can Effectively fend against the damage of external heat to the human body,But it also limits the loss of internal hent,which will lead to the heavy burden on the human thermal regulation system.In the meantime,due to the thick fabric and tight design of the protective clothing,it results in increase of risks of firefighters' heat stress,reduction of work efficiency and reduced duration.In order to ensure the Life health and improve the work efficiency of firefighters,it is necessary to carry out a profound study on the impact of protective clouting on human thermal response in hot environments.First,sweating guarded hotplates are utilized to measure the two most typical parameters of the thermal comfort performance of the protective clothing used for the firefighting;thermal resistance and evaporative resistanc.In addition,the thermal resistante and evaporative resistance of the protective clothing undcr different environmental conditions(15?30?),humidity(45%-90%),wind speed(0.1?1.5 m/s)are measured to explore,the effects of different conditions un the thermal comfort performance.Moreover,the puramelers such as total heat,loss,ventilation index,evaporation potential,ete.;are also figured out Based on this,the quantitative effects of ambient temperature,wind speed,humidity,etc.on thermal resiistance and humidity resistance,are proposed through statistical methuds such as fitting and regression.Secondly,the paper aims to analyze the impacts of protective clothing on the thermal physiology and psychology of firefighters in a high-temperature environment.Hence,the human thermal physiology and psychological experiments are conducted in the climate room.The environmental parameters of the artificial climate room are set at a temperature of 35?,a relative humidity of 45%,and a wind speed of 0.3 m/s.Each subject is required to wear basic clothing,basic clothing and protective clothing,basic clothing and protective clothing and cooling clothing in order to perform three groups of experiments.The subjects go through a rest-exercise process with the duration of one-hour experiment.During the experiment,the subjects' core temperature,skin temperature,heart rate,sweating rate and other physiological parameters and thermal sensations are measured and recorded.Psychological parameters such as thermal comfort,fatigue,skin and clothing wetness,activity limitation,and clothing comfort are also recorded and measured.The effects of different clothing combinations on the human body's thermal response are obtained in combination with the analysis and comparison of various parameters.Furthermore,the interaction between physiological and psychological effects is demonstrated woth the use of a fitting method.According to analysis of the results,the thermal resistance of protective clothing is significantly related to temperature and wind speed while the evaporative resistance has a close relationship with humidity and wind speed.Among them,the wind speed has the greatest impact on the overall thermal resistance and evaporative resistance,and the thermal comfort of protective clothing decreases under the human test conditions.The results present that the protective clothing will take great effects on the body's thermal physiological and psychological reactions,therefore,a substantial increase in the body's core temperature,skin temperature,heart rate and sweating rate will be produced.Additionally,the thermal sensation,thermal comfort,fatigue will reach the tolerance limit in a faster speed.The cooling suit has a certain inhibitory effect on the human's thermal physiological response,but it has little effect on the human's thermal psychological response limited by its own effective time.As time goes by,the negative effects on the human's physiology and psychology will be caused.Based on the results of linear regression and correlation analysis,the thermal psychological response of the human body is obviously affected by physiological parameters.Therefore,physiological cooling method has a positive effect on the psychological reaction of firefighters.