Several million American workers wear respirators on a regular basis, and the Occupational Safety and Health Administration (OSHA) requires that nonagricultural firms have a respiratory protection program. This article uses the OSHA inspection data base to examine all inspections in manufacturing in 47 states from 1999 through 2006; the examination starts with 1999 because an expanded OSHA respiratory program standard became effective in late 1998. The article identifies all inspections and all establishments at which respiratory protection (RP) violations were cited, and it compares the prevalence of violations by industry with the prevalence reported in a recent Bureau of Labor Statistics survey of respirator use. Multivariate analyses are used to identify the roles of industry, establishment size, union status, and employee participation in the inspection on noncompliance at the inspection level and for repeated inspections at the same establishment. The authors find that the pattern of noncompliance across industries mostly mirrors the survey findings about the prevalence of requirements for respirator use, although the chemical industry has fewer violations than expected. The probability of citing an RP violation is similar across establishment size categories, except for a large drop for establishments with over 200 workers. The presence of a worker accompanying the inspector increases the probability that a respiratory program violation will be cited; the presence of a union slightly decreases it.