Levels of indoor air pollutants, temperature and humidity over the study period.

Standard levels for indoor air quality control in public use facilities are set by the Ministry of Environment, Republic of Korea.All levels are written as geometric mean ± geometric standard deviation.Periods 1 to 4 are described in the methods section.PM10, particles 2.5, particles 1.0, particles 2, nitrogen dioxide; NOX, nitrogen oxide compounds; TVOC, total volatile organic compound; ppb, parts per billion.Levels of indoor air pollutants, temperature and humidity over the study period.