He C., Morawska L., Hitchins J., Gilbert D.
Bibliographic info:
Healthy Buildings 2003 - Proceedings 7th International Conference (7th-11th December 2003) - National University of Singapore - Vol. 1., pp 409-413, 1 Tab., 9 Ref.

As part of a larger indoor environmental study, residential indoor and outdoor levels ofnitrogen dioxide (NO2) were measured for 14 houses in a suburb of Brisbane, Queensland,Australia. Passive samplers were used for 48-h sampling periods during the winter of 1999.The average indoor and outdoor NO2 levels were 13.8 6.3 and 16.7 4.2 ppb, respectively.The indoor/outdoor NO2 concentration ratio ranged from 0.4 to 2.3, with a median value of0.82. The results of statistic analyses indicated that there was no significant correlationbetween indoor and outdoor NO2 concentrations, or between indoor and fixed site NO2monitoring station concentrations. However, there was a significant correlation betweenoutdoor and fixed site NO2 monitoring station concentrations. There was also a significantcorrelation between indoor NO2 concentration and indoor submicrometre (0.007-0.808 m)aerosol particle number concentrations. The results in this study indicated indoor NO2 levelsare significantly affected by indoor NO2 sources, such as a gas stove and cigarette smoking. Itimplies that the outdoor or fixed site monitoring concentration alone is a poor predictor ofindoor NO2 concentration.