Executive Summary

Indoor air quality was assessed in 10 randomly selected Fargo, ND bars both before and after a smoke-free indoor air ordinance. Six similar establishments were also randomly selected and sampled in Moorhead, MN where indoor smoking is prohibited. The concentration of fine particle air pollution, PM2.5, was measured with a TSI SidePak AM510 Personal Aerosol Monitor. PM2.5 is particulate matter in the air smaller than 2.5 microns in diameter. Particles of this size are released in significant amounts from burning cigarettes, are easily inhaled deep into the lungs, and cause a variety of adverse health effects including cardiovascular and respiratory disease and death. Key findings of the study include: Before the Fargo smoke-free air ordinance, the average level of fine particle indoor air pollution was 45 times higher in Fargo locations sampled compared to the places in smoke-free Moorhead. Employees working full-time in the establishments sampled in Fargo before the law were exposed annually to fine particle air pollution levels 4.5 times higher than the safe annual limit established by the U.S. Environmental Protection Agency (EPA). Indoor particle pollution levels declined 98 % in Fargo as a result of the smoke-free air law to low levels, similar to those found in outdoor air. Consistent with the findings of the U.S. Surgeon General, this study provides further evidence that indoor smoking causes exposure to harmful levels of indoor air pollution and that comprehensive smoke-free air policies, prohibiting indoor smoking, are extremely effective in eliminating these exposures. * p<0.001 for comparison of pre-law to post-law Fargo (paired samples t test of log-transformed values) * * p<0.001 for comparison of Fargo to Moorhead (Independent samples t test of log-transformed values) Note