Editor's note: The following article is part two of a two-part series. Part one was published in the February issue and provided background information about the topic.
Part one of this series provided details about the new Occupational Safety and Health Administration's (OSHA's) respirable crystalline silica (RCS) regulation's provisions, and the nature of the health hazards related to workplace silica exposure were discussed.
Following are specifics in the rule allowing for the use of objective data to assess worker exposure to RCS and some of NRCA's preliminary findings from initial air-monitoring sampling. The rule allows for use of objective data to exempt a contractor from air-monitoring requirements and provide a basis for respirator selection if necessary. OSHA notes reliance on objective data is intended to provide the same degree of assurance air monitoring of worker exposures through personal breathing samples does, so there is a specific record-keeping requirement. The rule requires objective data to reflect workplace conditions closely resembling the processes, material types, control methods, work practices and environmental conditions as in the contractor's current operations. Industry data are acceptable under the rule's definition of the term.