Abstract
The processes in the oil production industry are generally closed systems. The workers who clean and maintain process vessels, however, are exposed to the hazards of crude oil and confined spaces. Although respiratory protection is often used by these workers, exposures have not been documented and respirator selection procedures using detector tubes to measure benzene concentrations have not been validated. This study evaluates the effectiveness of this approach to respirator selection by examining actual exposures of a group of vessel workers and assessing the adequacy of protection that was provided. Personal breathing zone samples and area samples were collected by active adsorptive sampling during the cleaning of oil separators. Area air samples were also collected prior to entry into the vessels in conjunction with detector tube sampling conducted by safety personnel. Adsorptive air sampling indicated that exposure concentrations ranged from nondetectable to 5.8 ppm, averaged over the duration of an entry. Although there were inconsistencies in the relationship between measured benzene concentrations and selected respiratory protection, workers were always adequately protected according to the requirements of the Occupational Safety and Health Administration benzene standard.