Indoor environment and passengers' comfort in subway stations in Seoul

The purpose of this study is to investigate the indoor environment of subway stations and passengers' comfort in three seasons. Six subway stations in Seoul were selected for physical environment measurements and a survey of 5282 passengers; these two components were conducted together. The questionnaire addressed thermal, air, light, acoustic and overall comfort. Seoul subway stations had large differences in air temperature in some seasons, and the air temperature in winter was very low. The concentration of particulate matter (PM) and carbon dioxide satisfied the indoor air quality maintenance criteria. Most survey respondents felt 'neutral' about or 'comfortable' with the environment in the subway stations, even in very low temperatures. From the results of the correlation analysis between the SET* and the percentage of uncomfortable passengers, the comfort range was 16.1-31.2 SET*°C for the concourses and 15.9-31.5 SET*°C for the platforms, which was a wider range than previous studies from other countries.