Factors affecting indoor environmental air quality of non-smoking residences in Perth, Western Australia

This study investigated associations between a range of indoor air pollutants with household characteristics in 111 non-smoking residences located in Perth, Western Australia. Overall, the mean 24-hour indoor concentrations for PM 10 and PM 2.5 were below and above the World Health Organisation (WHO) (ambient) guideline values (GV) of 45 µg/m 3 and 15 µg/m 3 , respectively. Concentrations of measured gases were low, other than nitrogen dioxide (NO 2 ) which recorded a mean 24-hour concentration above the WHO GV (0.013ppm). Higher concentrations of total volatile organic compounds (TVOC) and carbon dioxide (CO 2 ) were observed as the number of household occupants increased. The type of heating and/or cooling appliances used was associated with higher concentrations of TVOC, CO 2 , carbon monoxide (CO), NO 2 and all size fractions of particulate matter (PM). Households that were opened daily for fresh air recorded higher concentrations of all PM size fractions and NO 2 when compared to those that were infrequently aired. These findings contribute to a better understanding of household characteristics that influence indoor air quality (IAQ) in homes where cigarette smoke, a significant contributor to residential air pollution, has been eliminated. These results are useful for modifying some behavioural choices by home occupants and can also inform meaningful risk mitigation strategies aimed at improving IAQ in residential settings.