Limiting Criteria for Human Exposure to Low Humidity

ASHRAE research project “Limiting criteria for human exposure to low humidity” was conducted in 2001-2002 at the Technical University of Denmark. The impact of humidity on comfort and working performance was measured subjectively and objectively at 5%rh, 15%rh, 25%rh and 35%rh at 22°C (71.6°F) and at 18°C, 22°C and 26°C at 2.4 g/kg. The effect of low humidity was observed at both clean and polluted indoor environment. The results found that low humidity had negative impact on mucous quality and working performance that requires visual attention. Some interactions between low humidity and air pollution on dryness symptoms were observed.