The purpose of Method 301 is to provide a set of procedures that the owner or operator of an affected source subject to requirements under 40 CFR part 63 can use to validate an alternative test method to a test method required in 40 CFR part 63, or to validate a stand-alone alternative test method based on established precision and bias criteria. The EPA is proposing revisions to existing Method 301. The proposed revisions include editorial, technical, and consistency changes in the language, tables, and equations of Method 301. Method 301 was originally published on December 29, 1992 [57 FR 61970], as a field validation protocol method. On March 16, 1994, Method 301 was included in 40 CFR 63.7 [59 FR 12430] to validate alternative test method requests. To date, subsequent revisions of Method 301 have not been changed to distinguish requirements for site-specific applications of the method versus a single validation for multiple sources.