INTRODUCTIONA local study completed in Singapore, which was part of an international multi-country study that aims to develop a global assessment of exposure to second-hand smoke in indoor workplaces, gathered data regarding the indoor air quality of public areas. It was hypothesised that air would be less polluted in non-smoking venues compared to places where smoking occurred.

MATERIALS AND METHODSA TSI SidePak AM510 Personal Aerosol Monitor was used to sample and record the levels of respirable suspended particles (RSP) in the air. A broad range of venues were sampled in Singapore. The primary goal of data analysis was to assess the difference in the average levels of RSP in smoke-free and non smoke-free venues. Data was assessed at 3 levels: (a) the mean RSP across all venues sampled compared with the mean levels of smoke-free and non smoke-free venues, (b) levels in venues where smoking occurred compared with similar venues in Ireland, and (c) comparison between smoke-free and non smoke-free areas according to the type of venue. Statistical significance was assessed using the Mann-Whitney U-test.

RESULTSThe level of indoor air pollution was 96% lower in smoke-free venues compared to non smoke-free venues. Averaged across each type of venue, the lowest levels of indoor air pollution were found in restaurants (17 microg/m3) and the highest in bars (622 microg/m3); both well above the US EPA Air Quality Index hazardous level of >or=251 ug/m3.

CONCLUSIONSThis study demonstrates that workers and patrons are exposed to harmful levels of a known carcinogen and toxin. Policies that prohibit smoking in public areas dramatically reduce exposure and improve worker and patron health.