The EPA has proposed revisions to Parts 51, 60, 61 and 63 to restructure the Stationary Source Audit Program. This will be of interest to anyone who is required to perform stack tests. Currently, the EPA provides audit materials free of charge, as ordered by the relevent regulatory authority overseeing the stack test, to quality assure various stack test methods. In the restructured program, the regulated facility will be required to purchase the audit materials from private accredited providers. Public comment period ends July 16, 2009.