Impact of Partial and Comprehensive Smoke-Free Regulations on Indoor Air Quality in Bars

In Korea, smoke-free regulations have been gradually implemented in bars based on venue size. Smoking bans were implemented in 2013 for bars ≥150 m(2), in 2014 for bars ≥100 m(2), and in 2015 for bars of all sizes. The purpose of this study was to determine indoor fine particle (PM(2.5)) concentrations in bars before and after implementation of the smoke-free policies based on venue size. Indoor PM(2.5) concentrations were measured with real-time aerosol monitors at four time points: (1) pre-regulation (n = 75); (2) after implementing the ban in bars ≥150 m(2) (n = 75); (3) after implementing the ban in bars ≥100 m(2) (n = 107); and (4) when all bars were smoke-free (n = 79). Our results showed that the geometric mean of the indoor PM(2.5) concentrations of all bars decreased from 98.4 μg/m(3) pre-regulation to 79.5, 42.9, and 26.6 μg/m(3) after the ban on smoking in bars ≥150 m(2), ≥100 m(2), and all bars, respectively. Indoor PM(2.5) concentrations in bars of each size decreased only after the corresponding regulations were implemented. Although smoking was not observed in Seoul bars after smoking was banned in all bars, smoking was observed in 4 of 21 bars in Changwon. Our study concludes that the greatest decrease in PM(2.5) concentrations in bars was observed after the regulation covering all bars was implemented. However, despite the comprehensive ban, smoking was observed in bars in Changwon. Strict compliance with the regulations is needed to improve indoor air quality further.