40 CFR § 761.320
Applicability
June 9, 2020
This subpart describes self-implementing comparison testing requirements for chemical extraction and chemical analysis methods used as an alternative to the methods required in §761.272 or §761.292. Any person conducting comparison testing under this subpart must comply with the requirements of §761.80(i), including notification. Use alternative methods only after successful completion of these comparison testing requirements and after documentation of the results of the testing.