Background
The objective of the present study was to assess the smoking prevalence of workers, the attitudes toward smoking, and exposure to environmental tobacco smoke (ETS) in different work environments. Methods A questionnaire survey and indoor air quality (IAQ) measurements including the concentration of gaseous nicotine in indoor air were performed in 10 medium-sized and large-scale workplaces representing industrial, service, and of®ce environments. The questionnaire was distributed to all workers (n 1471) in 10 workplaces. IAQ measurements were performed in 4±7 locations in each workplace. Results Altogether 1027 (70%) employees, of whom 31% were women, responded to the questionnaire. Prevalence of daily smokers was 28.3% (32.3% for men and 22.9% for women). The prevalence was highest among workers in the service sector (32.7%) and lowest in of®ces (21.6%). Among smokers, 86% of men and 75% of women smoked inside the building. Exposures greater than one hour to ETS were highest in industry (66.3%) and lowest in services (42.6%). Non-smokers complained more often than the regular smokers about the spreading of tobacco smoke to non-smoking areas, and they felt that workplace smoking was a signi®cant discomfort. Mean concentration of nicotine was highest in service environments (3.0 "g/m 3 ) and lowest in of®ces (0.6 "g/m 3 ). Conclusions According to the present questionnaire survey and IAQ measurements, smoking habits and exposure to tobacco smoke varied considerably depending on the position of the employees and the type of the workplace.