Indoor/Outdoor Relationships of Organic Carbon (OC) and Elemental Carbon (EC) in PM sub(2.5) in Roadside Environment of Hong Kong

• Published in: Atmospheric environment (1994) 2004-12, Vol.38 (37), p.6327-6327
• Main Authors: Ho, K F, Cao, J J, Harrison, Roy M, Lee, S C, Bau, K K
• Format: Article
• Language: English
• ISSN: 1352-2310
• DOI: 10.1016/j.atmosenv.2004.08.007

Indoor and outdoor concentrations of organic carbon (OC) and elemental C (EC) in PM sub(2.5) were measured at an office, a classroom with mechanical ventilation, and at three residences with natural ventilation. All five buildings were located near roads in Hong Kong. Indoor and outdoor PM sub(2.5) concentrations ranged 15.3 108.0 and 27.8 197.0 mu g/m super(3), respectively, and the indoor/outdoor ratios ranged 0.2 1.6. The strong indoor-to-outdoor PM sub(2.5) association, especially for the buildings with natural ventilation, suggested that the fine particulates were mainly from the outdoor environment. The average indoor and outdoor concentrations of total C were 16.1 and 19.2 mu g/m super(3), respectively, while those for EC and OC were 4.8 and 6.4 mu g/m super(3) and 11.3 and 12.6 mu g/m super(3), respectively. Clearly, OC was enriched in the indoor air. Higher indoor/outdoor ratios of OC and EC were noted in naturally ventilated residences than in mechanically ventilated buildings.