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Program 3 applicability and NAICS code determination

A covered process that is ineligible for Program 1 will be subject to Program 3 requirements if the process is in one of ten specified North American Industrial Classification System (NAICS) codes, or is subject to the OSHA Process Safety Management (PSM) standard (40 CFR Part 68.10(d)). When determining Program 3 applicability for a particular process, should the owner or operator use the primary NAICS code that describes the stationary source's main business?

No. The owner or operator must determine the individual NAICS code for each covered process to determine whether Program 3 applies (61 FR 31670; 6/20/96). The assigned NAICS code should reflect the activity of the process, and will not necessarily be the same as the source's overall primary NAICS code.