The effect of outdoor air and indoor human activity on mass concentrations of PM sub(1) sub(0), PM sub(2) sub(.) sub(5), and PM sub(1) in a classroom

• Published in: Environmental research 2005-10, Vol.99 (2), p.143-149
• Main Authors: Branis, M, Rezacova, P, Domasova, M
• Format: Article
• Language: English
• ISSN: 0013-9351
• DOI: 10.1016/j.envres.2004.12.001

The 12-h mass concentration of PM sub(1) sub(0), PM sub(2) sub(.) sub(5), and PM sub(1) was measured in a lecturing room by means of three co-located Harvard impactors. The filters were changed at 8 AM and at 8 PM to cover the periods of presence and absence of students. Concentrations were assessed by gravimetry. Ambient PM sub(1) sub(0) data were available for corresponding 12-h intervals from the nearest state air-quality-monitoring network station. The data were pooled into four periods according to the presence and absence of students-Monday-Thursday day (workday daytime), Monday-Thursday night (workday night), Friday-Sunday day (weekend daytime), and Friday-Sunday night (weekend night). Average indoor workday daytime concentrations were 42.3, 21.9 and 13.7 mu gm super(-) super(3), workday night were 20.9, 19.1 and 15.2 mu gm super(-) super(3), weekend daytime were 21.9, 18.1 and 11.4 mu gm super(-) super(3), and weekend night were 24.5, 21.3, and 15.6 mu gm super(-) super(3) for PM sub(1) sub(0), PM sub(2) sub(.) sub(5), and PM sub(1), respectively. The highest 12-h mean, median, and maximum (42.3, 43.0, and 76.2 mu gm super(-) super(3), respectively) indoor concentrations were recorded on workdays during the daytime for PM sub(1) sub(0). The statistically significant (r=0.68,P