摘要:This is the first study to examine the prevalence of self-reported smoke-free rules for private cars and homes before and after the passage of a smoke-free vehicle law. Data were examined for 13,461 Maine adults aged 18 or older who participated in the Behavioral Risk Factor Surveillance System, a state-based telephone survey covering health topics. Self-reported smoke-free car and home rules, smoking behavior, and demographic variables of age, sex, education, income, and children in household were analyzed for prevalence before and after the state's smoke-free vehicle law was passed. Prevalence of smoke-free car and home rules was significantly higher after Maine's smoke-free vehicle law was passed in the state (P = .004 for car rules and P = .009 for home rules). Variations in smoking rules differed by smoking and demographic variables. People with household incomes of less than $20,000 saw an increase of 14.3% in smoke-free car rules; overall, those with annual incomes of less than $20,000 and those with less than a high school education reported a lower prevalence of smoke-free car rules both before and after the law was passed than did people with higher incomes and higher education levels. The prevalence of smoke-free home rules after the law was implemented was higher among those with 4 or more years of college education than among those with lower levels of education (P = .02). The prevalence of smoke-free car and home rules among Maine adults was significantly higher after the passage of a statewide smoke-free vehicle law. This apparent change in smoke-free rule prevalence may be indicative of changing social norms related to the unacceptability of secondhand smoke exposure.