A thermal comfort field study on subway passengers during air-conditioning season in Beijing.

With the massive increase of subway passengers in large Chinese cities, thermal comfort in the subway has become an important topic. The thermal comfort of subway passengers is different from that in above-ground buildings and has its own particularities, as the subway comprises of underground semi-closed buildings. Moreover, the thermal environment experienced by passengers is dynamic. Considering these reasons, this study adopts a dynamic thermal comfort study method for investigating thermal sensations in the subway. The field study was conducted in two Beijing subway stations in May 2016 and June–July 2017, and a total of 628 samples were obtained. Variations in thermal sensation and thermal comfort were analyzed. The results showed that the thermal sensations of subway passengers change dramatically through the entire process, and alternate between hot and cold. For the station hall and platform, although the temperature and the relative humidity were beyond the standard range of the "Code for Design of Metro in China" (GB50157- 2013), passengers find them acceptable. The study also provides reliable basic data for the design and operation management of ventilation and air-conditioning systems in the subway station, so as to create a comfortable thermal environment for subway passengers. [ABSTRACT FROM AUTHOR]