ASHRAE Standard 62.1 is the basis for most commercial ventilation system designs in the United States. Comparisons between the actual performance of these buildings and their designs are often difficult to find in the open literature. This paper reports carbon dioxide tracer gas measurements of ventilation rates in bars and restaurants in Minnesota prior to implementation of a statewide smoking ban. Seventy-five percent of the estimated ventilation rates were less than those required for the default occupancies of the 65 bars and restaurants sampled. On the other hand, 80% of these venues had acceptable ventilation rates based on the actual occupancies observed during the measurements. This suggests that high pollutant concentrations in the bars and restaurants were driven by large pollutant sources, not by low ventilation rates.