Experimental study on a radiant leg warmer to improve thermal comfort of office workers in winter

Office workers spend most of their working time seated in their own stations. When people keep sitting for a long time, they tend to feel cold legs and feet in winter, which affect their thermal comfort. In this study, radiant leg warmers were provided to office workers to warm their lower legs in winter condition. The improving effect of the leg warmers on thermal comfort was studied. The thermal environment parameters and physiological parameter were measured (including heart rate, blood pressure, skin temperature, ear canal temperature and fingertip blood perfusion). Subjective questionnaires were collected, involving local and overall thermal sensation, thermal comfort, thermal preference, etc. Cognition tests were conducted including the Stroop Color and Word Test and the Pointer Table Test. The results showed that the use of leg warmers improved their mean skin temperature and local skin temperature effectively. The ear canal temperature was unchanged before and after the use of leg warmers. Peoples' fingertip blood perfusion tended to decrease during experiments, and the use of leg warmer slowed down this trend. The subjective responses showed that the thermal sensation and thermal comfort were significantly improved. The results of cognitive ability tests found that, when the leg warmer was used, the task completion time did not change much, while the error rate decreased. In general, for office workers, the leg warmer can effectively improve their thermal comfort and related physiological parameters in cold environment in winter.