Background: Many states and cities have adopted laws restricting smoking in public places. Health departments generally regard the laws as self-enforcing, implying little need for monitoring or enforcement. Whether this achieves good compliance at the workplace, a major site of passive smoke exposure, is not known.
Methods: We assessed workplace compliance with a no-smoking ordinance in Cambridge, Massachusetts, by conducting telephone surveys of two stratified random samples of city businesses, 3 and 24 months after the law took effect. Response rates were 76% at 3 months (n = 312) and 79% at 24 months (n = 317).
Results: Employers' awareness and approval of the law were initially high. Approval remained high, but awareness declined over 2 years, from 92 to 73% (P < 0.0001), and employers' knowledge of the law's requirements was incomplete. Eighty percent of companies restricted smoking 3 and 24 months after the law, but only half of businesses fully complied with the law at either time. On multivariate analysis, compliance was significantly better in businesses that were aware of the law, in favor of it, and whose owners were nonsmokers. One fifth of firms with smoking policies cited the law as a reason for policy adoption.
Conclusion: A self-enforcement approach to implementing a no-smoking law achieved high levels of awareness and intermediate levels of compliance in a city's businesses. Awareness of the law declined over 2 years without reinforcement. The law was popular with employers and was associated with a high level of smoking restrictions in city businesses, but further efforts are needed to maximize compliance with a no-smoking law and reduce workplace smoke exposure.