高温暴露对人员作业能力的影响规律与机理

In recent years outdoor human work safety and productivity are threatened by the frequent occurence of high temperature events in China. Physiological health and work ability (performance) are the two main factors to work safety under high temperature. The importance of physiological health has been realized and the existing legislation of work safety was established based on physiological health. However, another factor, work ability, is always ignored, which leads to the limitations of the safety legislation. Impaired work ability can cause serious incidents in high temperature environment. Moreover, work ability is impaired by high temperature before physiological health. Therefore, human work ability should also be used as an important index to evaluate a worker's safety when working under high temperature. This is the key to solve the problem of outdoor work safety and productivity. However, the law and mechanism of the effect of high temperature on work ability are not revealed yet, due to the very limited related studies. This project will carry out a thorough study on the impact of high temperature exposure on workers' ability (the physical and mental activity abilities). In this study, the variation in work ability with high temperatures will be obtained for different work intensity and the mechanism for the variation will be explored. The results of the study will provide reliable basis for significantly improving the existing legislation of work safety. As a result, human work safety and productivity under high temperature can be greatly enhanced.

近年来我国高温气候频繁出现，室外作业安全与效率问题随之凸显。高温导致作业人员安全事故主要有两大因素：生理健康和作业能力。目前，国内外针对高温作业安全的定义、标准及法规均是基于生理健康因素提出，并未考虑作业能力因素，导致其作用有限。高温环境中人员作业能力的显著降低易引发安全事故，而且作业能力先于生理健康受到高温的损害。因此，在保障生理健康安全的基础上，也将作业能力作为评价人员作业安全的重要指标，是解决室外作业安全与效率问题的关键。然而，有关高温环境影响人员作业能力的研究至今非常有限，其影响规律与机理仍未得到有效揭示。为此本项目深入系统地研究高温暴露对人员作业能力（体力与脑力）的影响，获得不同劳动强度下作业能力随高温的变化规律，并对影响规律的形成机理进行深入探讨。这一项目的成功实施将为建立更为完善细致的高温环境作业标准和法规提供可靠的理论依据，进而为实现高温环境人员的安全高效作业提供有力保障。

高温气候导致频发的作业安全事故和作业效率降低。未来极端高温气候出现可能更加频繁。建立更为完善细致的高温环境作业标准和法规很有必要且势在必行，而其关键则需要新的思路和可靠的理论基础。. 本项目开展了高温暴露人体实验。分别针对静坐和运动状态人员进行高温暴露实验。实验温度为26、30、33、37度，相对湿度为50%和70%。实验中测量体温调节活动相关生理指标，采用问卷调查热感觉、空气品质感知度和急性健康症状，进行神经行为测试评价认知能力。.基于实验数据，围绕高温高湿环境人体生理反应、主观感觉和认知表现的影响规律与机理开展了深入分析。主要结果包括：.（1）高温导致增强的体温调节活动，如鼓膜温度、心率、平均皮温、体重损失、收缩压显著增加，呼出气流量和呼吸频率显著升高，血氧饱和度显著下降。.（2）高温对人体主观感觉产生不利影响。环境温度37度时受试者感觉很热且不舒适，温度不可接受，感知空气品质不可接受、空气新鲜度降低，尽管气味强度感觉轻微。.（3）高温引起神经行为症状增强。环境温度37度时受试者感觉头更痛、更晕、思考困难、疲倦、专注力下降；警觉性也显著下降。.（4）高温导致认知表现降低。尤其对于中等运动强度人员，37度时的神经行为测试出现显著降低；而且，受试者完成测试需付出更多的努力。.（5）高温环境中空气相对湿度的升高会增强高温对人体生理反应和主观感觉的不利影响，同时降低认知表现。.（6）高温环境中活动强度的提升会加重人体承受的热应力，如更快的心率、更高的体温和更高的皮肤温度。.（7）高温环境中脑电波信号的功率谱分析结果与认知测试成绩有显著的线性关系。.（8）新陈代谢率随温度升高呈下降趋势，可能是人体应对高温的一种自主性保护方式。. 本项目研究成果为深入理解高温影响人体安全和效率提供了理论基础，也为建立更为完善细致的高温环境作业标准提供了理论依据。