Department of Building and Real Estate, Hong Kong Polytechnic University, 11 Yuk Choi Road, Hung Hom, Kowloon, Hong Kong, China.
Ann Work Expo Health. 2017 May 1;61(4):481-494. doi: 10.1093/annweh/wxx007.
This study aims to evaluate the effectiveness of a newly designed hybrid cooling vest for construction workers in alleviating heat stress.
Two types of cooling vests, namely, a commonly worn Vest A and a newly designed Vest B, were tested in a climatic chamber environment (34.0°C temperature, 60% relative humidity, and 0.4 m s-1 air velocity) using a sweating thermal manikin. Four test scenarios were included: fan off with no phase change materials (PCMs) (Fan-off), fan on with no PCMs (Fan-on), fan off with completely solidified PCMs (PCM + Fan-off), and fan on with completely solidified PCMs (PCM + Fan-on).
Test results showed that Vests A and B provided a continuous cooling effect during the 3-h test. The average cooling power for the torso region of Vest B was 67 W, which was higher than that of Vest A (56 W). The addition of PCMs offered a cooling effect of approximately 60 min. Ventilation fans considerably improved the evaporative heat loss compared with the Fan-off condition.
The newly designed hybrid cooling vest (Vest B) may be an effective means to reduce heat strain and enhance work performance in a hot and humid environment.
本研究旨在评估一种新设计的混合冷却背心对建筑工人缓解热应激的效果。
在气候室环境(34.0°C 温度、60%相对湿度和 0.4 m s-1 空气速度)中使用出汗热模型对两种冷却背心,即通常穿着的 Vest A 和新设计的 Vest B 进行测试。包括四个测试场景:无相变材料(PCM)的风扇关闭(Fan-off)、无 PCM 的风扇开启(Fan-on)、完全凝固 PCM 的风扇关闭(PCM + Fan-off)和完全凝固 PCM 的风扇开启(PCM + Fan-on)。
测试结果表明,背心 A 和 B 在 3 小时的测试中提供了持续的冷却效果。背心 B 躯干区域的平均冷却功率为 67 W,高于背心 A(56 W)。PCM 的添加提供了大约 60 分钟的冷却效果。通风风扇与 Fan-off 条件相比,显著提高了蒸发散热损失。
新设计的混合冷却背心(Vest B)可能是一种有效手段,可以减轻湿热环境中的热应激并提高工作表现。