The effectiveness of designated smoking areas in controlling non-smokers exposure to environmental tobacco smoke.

Field monitoring was conducted in office buildings in Seattle and Dallas to assess the effectiveness of various workplace smoking configurations in controlling non-smokers exposure to environmental tobacco smoke (ETS). Simultaneous measurements of vapour-phase and particle-phase tracers of ETS were conducted in adjacent smoking and non-smoking areas. Pressure relationships between smoking and non-smoking areas were determined. The Seattle portion of the study focused on the direct infiltration of ETS from smoking to non-smoking areas, as minimal recirculation of return air was occurring. Negative pressurisation of smoking areas eliminated the direct migration ofETS. Tracers ofETS exposure were not detected in non-smoking areas adjacent to negatively pressurised smoking lounges. In the Dallas study buildings, the impact of recirculation of ETS through the heating, ventilation and air-conditioning systems was assessed. Vapour-phase ETS constituents were recirculated into non-smoking areas at diluted concentrations. However, elevated particle-phase constituents were not found in non-smoking areas. The overall results indicate that non-smokers exposure to ETS can be effectively reduced in the office workplace without regulations or policies that require either direct exhaust of air from smoking areas to the outdoors by dedicated ventilation systems or total prohibition of smoking within buildings.