Experimental study on improvement effect of a cooling vest on thermal comfort of manufactory workers. (1st June 2023) - Liu, Bingbing
Abstract: This study aimed to examine the effect of a personal cooling vest on improving the thermal comfort of workers in a warm and hot indoor environment. The experiments were conducted under three temperatures: 27 °C, 29 °C, and 31 °C. Twenty subjects (10 males and 10 females) were recruited. They were required to perform three activities (i.e., sitting, light packing and heavy packing activity). Subjects experienced two scenarios: the one wearing the cooling vest (CV), and the other without the cooling vest (NCV). The skin temperature and peripheral oxygen saturation (SpO2) were measured. Subjects' thermal comfort and sensation votes were collected, and their responses to two cognitive tasks and working efficiency were also recorded. The use of CV reduced subjects' local and mean skin temperature effectively. Compared with the light packing activity, the decrease of local and mean skin temperature was smaller during heavy packing. With the use of CV, the SpO2 in the three activities and work efficiency in the two packing activities tended to increase. The result of subjective responses showed that their thermal sensation and comfort votes were also significantly improved by the use of CV. With the increase of activity level, the improving effect tended to decline, in which the decrement of thermal sensation vote became smaller in the heavy packing activity. The results of cognitive ability tests showed that the tasks' completion time was not affected by the use of CV, while the error rate of the Stroop test decreased. Highlights: A cooling vest (CV) with phase change material was proposed for manufactory workers. Cooling effect of CV tended to decrease as the activity level increased. Reduction in thermal sensation was correlated to reduction in local skin temperature. With the use of CV, subjects' work efficiency increased slightly.