Table 2 Smoking behaviours among smokers by type of smoking policy in their workplace imposed for 3 or 10 years Policy in place for Policy in place for 3 years 10 years Restricted Smoke free Restricted Smoke free (N[33)% (N[126)% (N[355)% (N[106)% Cigarettes smoked daily Light 6.1 31.7* Moderate 60.6 55.6 Heavy 33.3 12.7* Very heavy e e Time to ﬁrst cigarette after waking (min) <5 6.1 4.8 6e30 57.6 33.3* 31e60 30.3 23.0 >60 6.0 38.9* Quitting intention No intention in next 6 months 33.3 51.6 Intend quitting within 6 months 57.6 39.7 Intend quitting within 1 month 9.1 8.7 No. of quitting attempts in past 12 months 0 33.3 14.3* 1 24.2 14.3 2 24.2 32.5 >2 18.2 38.9* Self-conﬁdence about quitting Will not succeed 6.1 9.5 May not succeed 18.2 12.7 Uncertain 45.5 20.6* May succeed 24.2 39.7 Will succeed 6.0 17.5* Willing to attend company cessation programme Yes 55.6 75.8 No 44.4 24.2* *p<0.05. 21.1 44.8 27.3 6.8 17.2 36.6 16.1 30.1 55.8 36.0 8.2 48.5 20.0 9.0 22.5 10.1 16.3 25.4 28.7 19.5 71.7 28.3 30.2 48.1 20.8 0.9* 9.4* 32.1 20.8 37.7 58.5 36.8 4.7 46.2 14.2 10.4 29.2 10.4 11.3 30.2 36.8 11.3 70.0 30.0 10-year policy group. The proportion of smokers who smoked their ﬁrst cigarette within 5 min after waking up was the highest (17.2%) in 10-year restrictive smoking workplaces. This was nearly two times the proportion (9.4%) in the 10-year smoke-free workplaces and three times that of the workplaces with 3-year policies (4.8% to 6.1%). The workplaces with restrictive smoking policies had the highest numbers of very heavy smokers (6.8%) compared to all other groups (0% to 0.9%). Although a majority (70%) of all smokers believed smoking had a moderate to severe impact on their health, nearly a quarter of employees thought smoking was either harmless or had only a mild impact on their health. Around 15% of smokers believed that quitting smoking even had a negative impact to their health. These ﬁndings were similar to the results of the 1996 China National Smoking Prevalence Survey and the results of previous research.10 11 However, around 90% of smokers were supportive of smoking policies in workplaces and public settings. The results of multiple logistic and linear regression analyses on the relationship between daily cigarette consumption and quitting intention and potential confounders are shown in table 3. No signiﬁcant association between age and daily ciga- rette consumption was found among workplaces with 3 years of smoking policy implementation. But smokers from workplaces with 10 years of restrictive smoking control policies who were aged more than 40 years consumed more cigarettes, 3e3.8 per day, than younger smokers. However, the smokers in the over 50 Tobacco Control 2011;20:131e136. doi:10.1136/tc.2010.036335 Research paper age group were twice as likely to intend to quit as smokers aged less than 30 years. Education was not associated with daily cigarette consump- tion, or with quitting intention. The professional group from workplaces with 10 years of restrictive smoking policies smoked signiﬁcantly lessd2.5 cigarettes per daydthan production operators (p<0.01). The laboratory technicians from workplaces with smoking policies in place for 3 years had signiﬁcantly stronger quitting intentions, while similar responses were also found in the sales and marketing groups from the workplaces that had smoking control policies in place for 10 years. For unknown reasons, smokers from workplaces that had had smoking policies for 10 years showed more signiﬁcant quitting attempts over the past year and more conﬁdence with regard to their quitting results. This was not found among the employees from the workplaces that had had smoking policies for 3 years. Smokers who were willing to participate in a company sponsored cessation programme were unsurprisingly 3e6 times more likely to intend to quit smoking than those uninterested in the company cessation programme (p<0.01), no matter how long the smoking control policies had been imposed at their workplaces. For workplaces with 3-year smoking policies, employees from completely smoke-free workplaces smoked signiﬁcantly less (3.4 cigarettes per day) than smokers from workplaces with only restrictive smoking policies (p<0.01). However, this impact was not seen between the workplaces where smoking policies had been in place for 10 years. No signiﬁcant association was found between workplace smoking control policies and smokers’ quitting attitudes regardless of how long the smoking policies had been in place. DISCUSSION This is the ﬁrst study in China to investigate smoking control policies in plants and their association with employee smoking behaviours, as well as their changes over time. The results show that workplace smoking control policies may have a strong association with smoking prevalence and daily cigarette consumption, but their association with smokers’ quitting intentions is weak. This association seems more signiﬁcant among workplaces that have had their policies in place for a shorter time. Workplace smoke-free policy appeared to have a strong asso- ciation with lower smoking prevalence, as well as reducing the number of cigarettes smoked. Smoke-free policies were also associated with a greater proportion of light smokers, fewer heavy smokers and a longer time until ﬁrst cigarette after waking. The patterns of smoking prevalence and daily cigarette consumption in restrictive smoking workplaces were quite similar to that reported in the 2002 China national smoking survey, although the majority of workplaces in the national survey did not restrict onsite smoking at all.12 Our results are also consistent with the ﬁndings of a Taiwanese study in which the smoking prevalence of male employees was signiﬁcantly lower (29.5%) in workplaces with prohibitive smoking policies than those with either restrictive (42.7%) or unrestricted policies (44.5%).13 The pronounced effects of a completely smoke-free workplace on smoking prevalence and daily cigarette consumption may have decayed over time: the signiﬁcant impact found in the workplaces where smoke-free policies had been imposed for 3 years was not found in workplaces where the policy had been implemented for 10 years. Smoking prevalences in workplaces where restrictive or smoke-free smoking policies had been 133