Abstract: The construction industry occupies a pivotal position in China's economy, and with the acceleration of urbanization, the demand for construction workers is growing. However, the construction industry is a field with frequent accidents, particularly in summer's high-temperature environments, where the labor safety of construction workers has garnered significant attention. The combination of high temperature and humidity, coupled with intense physical labor, can easily lead to a rapid rise in body temperature. Therefore, implementing effective thermal protection measures for construction workers exposed to such environments is crucial. In situations where the external working environment cannot be altered, active cooling clothing has emerged as an effective means to regulate heat stress and cope with outdoor high-temperature work. This type of clothing can be mainly classified into air-cooled, liquid-cooled, phase change material (PCM)-based, and fan-assisted varieties.
Hence, this study employed an artificial climate chamber set at 35°C with 75% relative humidity to simulate the real environment of a construction site in summer and mimicked the process of heavy lifting tasks (such as raising, carrying, transferring, and unloading goods). Eight male subjects completed the experiments while wearing phase change ventilation clothing (combining PCM with built-in fans) and ordinary workwear, respectively. Objective physiological data (including average skin temperature, temperature and humidity under the torso clothing, sweat production, and sweat evaporation rate) and subjective evaluations (tests on cognitive interference suppression, attention level, reaction time, as well as assessments of thermal sensation, thermal comfort, and humidity sensation) were collected. Data analysis was conducted using methods such as repeated measures ANOVA and paired-samples t-tests, aiming to assess the physiological states of the subjects when they wear different types of clothing, subsequently, so as to evaluate the cooling performance of the phase change ventilation clothing in construction work.
The research results indicate that the phase change ventilation clothing significantly reduces human skin temperature, temperature and humidity under the clothing, and sweat production. By enhancing convection with the built-in fan to promote sweat evaporation, it effectively inhibits the continuous rise of body temperature after exercise. Additionally, it aided in recovering from the negative impacts on cognitive self-control caused by high-temperature and high-humidity environments, as well as intense physical activities. However, the condensation water produced during the melting process of PCM increases the humidity under the torso clothing. Moreover, under high-intensity work in summer, the effect of the phase change ventilation clothing on improving human thermal comfort is limited, and its continuous cooling ability is unstable. Future research could consider developing slow-melting materials or improving the design of cooling fans to enhance cooling effects and ventilation performance, so as to further improve the work comfort of construction workers in high-temperature environments.

Key words: phase change ventilation clothing, construction workers, thermoregulation, thermal and humid sensation, skin temperature

摘要： 为缓解夏季高温环境对人体作业产生的负面影响，模拟真实高温环境中建筑工人的系列搬运动作，探究工人所穿相变通风服的降温性能与热湿舒适性能。在温度为35 ℃、相对湿度75%的人工气候舱内，8位男性受试者穿着相变通风服与普通工作服完成了对比实验，通过测量客观生理数据、主观认知测评、舒适感评分等分析服装对人体降温的实际影响。结果显示：相变通风服能显著降低人体皮肤温度和衣下温湿度、提升汗液蒸发率，有效抑制运动结束后体温持续上升的趋势，修复高温高湿环境与剧烈运动对于自我认知控制的损害。但建筑作业运动强度大，相变通风服对提升建筑作业环境中的人体热舒适的效果有限，且持续降温能力不稳定，未来可设计慢熔化材料或制冷风扇，以持续降温为主，并辅以通风来进一步提升实际高温环境下建筑作业的热湿舒适性。

关键词: 相变通风服, 建筑工人, 体温调节, 热湿感觉, 皮肤温度