Finland the Tobacco Act was amended in 1994 to include workplaces, The developed method for estimating passive smoking, or environmental tobacco smoke utilised the widely used measurement of volatile organic compounds in indoor air quality surveys. The method is based on active sorbent sampling, thermal desorption and gas chromatography/mass selective detection (GC/MS) analysis and it has been tested in a chamber and in field conditions. The method can be used simultaneously to measure volatile organic compounds and exposure to tobacco smoke, We recommend nicotine, collected by active sampling, as an indicator for the evaluation of the exposure to environmental tobacco smoke spreading from smoking areas. (C) 1998 British Occupational Hygiene Society. Published by Elsevier Science Ltd.