Introduction: A revised indoor air quality law has been implemented in Virginia to protect the public from the harmful effects of secondhand smoke exposure. This legislation contains exemptions that include allowances for smoking in a room that is structurally separated and separately ventilated. The objective of the current study was to examine the impact of this law on air quality in waterpipe cafés, as well as to compare the air quality in these cafés to restaurants that allow cigarette smoking and those where no smoking is permitted.
Methods: Indoor air quality in 28 venues (17 waterpipe cafés, five cigarette smoking-permitted restaurants and six smoke-free restaurants (five with valid data)) in Virginia was assessed during 4 March to 27 May 2011. Real-time measurements of particulate matter (PM) with 2.5 μm aerodynamic diameter or smaller (PM2.5) were obtained and occupant behaviour/venue characteristics were assessed.
Results: The highest mean PM2.5 concentration was observed for waterpipe café smoking rooms (374 μg/m(3), n=17) followed by waterpipe café non-smoking rooms (123 μg/m(3), n=11), cigarette smoking-permitted restaurant smoking rooms (119 μg/m(3), n=5), cigarette smoking-permitted restaurant non-smoking rooms (26 μg/m(3), n=5) and smoke-free restaurants (9 μg/m(3), n=5). Smoking density was positively correlated with PM2.5 across smoking rooms and the smoke-free restaurants. In addition, PM2.5 was positively correlated between smoking and non-smoking rooms of venues.
Conclusions: The PM2.5 concentrations observed among the waterpipe cafés sampled here indicated air quality in the waterpipe café smoking rooms was worse than restaurant rooms in which cigarette smoking was permitted, and state-required non-smoking rooms in waterpipe cafés may expose patrons and employees to PM2.5 concentrations above national and international air quality standards. Reducing the health risks of secondhand smoke may require smoke-free establishments in which tobacco smoking sources such as water pipes are, like cigarettes, prohibited.
Keywords: Secondhand smoke; addiction; air quality; behavioural pharmacology; cigarette; dependence; electronic nicotine delivery devices; environmental tobacco smoke; exposure assessment (ETS); harm reduction; nicotine; non-cigarette tobacco products; taxation and price; toxicology; waterpipe; withdrawal.