Background China has enacted subnational smoke-free legislations, which requires compliance evaluations to provide data for future implementation planning. This study comprehensively assessed smoke-free regulation compliance in Xining in Western China.

Methods Conducted in November and December 2023, the study used a mixed-methods design. Quantitative surveys of observing the existence of ‘no evidence of smoking’ were completed by trained investigators in 1007 venues (including 2553 indoor and 55 outdoor areas). PM2.5 concentration assessments of evidence of smoking were performed in 48 venues. Staff interviews on perceptions and implementation of the regulations were conducted in 94 venues.

Results In the quantitative survey, the compliance rate of ‘no evidence of smoking’ in indoor areas ranged from 65.2% to 100% by venue types, with public transportation vehicles (100%) and educational institutions (90%) showing the highest rates and leisure/entertainment/accommodation venues showing the lowest. The compliance rate in outdoor areas was 88.5% for health institutions and 96.4% for educational institutions. The PM2.5 monitoring found six venues (one hospital and five leisure/entertainment/accommodation venues) had an average PM2.5 concentration level exceeding China’s air quality standard, which were highly likely caused by people smoking. Qualitative interviews revealed that lack of commitment and knowledge to regulations among venue staff and non-cooperation of smoking clients might be the main reasons contributing to unsatisfactory compliance.

Conclusion The study provided empirical data on the compliance with local smoke-free regulations in Xining and identified a room for improvement. Efforts should be made to raise public awareness of smoke-free regulations and strengthen regulations’ enforcement and supervision.