Method 301
Field Validation of Pollutant Measurement Methods From Various Waste Media
40 CFR Part 63, Appendix A
From the method — regulatory text
Sections 1.0 and 2.0 of Method 301—Field Validation of Pollutant Measurement Methods From Various Waste Media, as published at 40 CFR Part 63, Appendix A. Retrieved 10/07/2026. The full method is on the eCFR.
1.0 What is the purpose of Method 301?
Method 301 provides a set of procedures for the owner or operator of an affected source to validate a candidate test method as an alternative to a required test method based on established precision and bias criteria. These validation procedures are applicable under 40 CFR part 63 or 65 when a test method is proposed as an alternative test method to meet an applicable requirement or in the absence of a validated method. Additionally, the validation procedures of Method 301 are appropriate for demonstration of the suitability of alternative test methods under 40 CFR parts 59, 60, and 61. If, under 40 CFR part 63 or 60, you choose to propose a validation method other than Method 301, you must submit and obtain the Administrator's approval for the candidate validation method.
2.0 What approval must I have to use Method 301?
If you want to use a candidate test method to meet requirements in a subpart of 40 CFR part 59, 60, 61, 63, or 65, you must also request approval to use the candidate test method according to the procedures in Section 16 of this method and the appropriate section of the part (§ 59.104, § 59.406, § 60.8(b), § 61.13(h)(1)(ii), § 63.7(f), or § 65.158(a)(2)(iii)). You must receive the Administrator's written approval to use the candidate test method before you use the candidate test method to meet the applicable federal requirements. In some cases, the Administrator may decide to waive the requirement to use Method 301 for a candidate test method to be used to meet a requirement under 40 CFR part 59, 60, 61, 63, or 65 in absence of a validated test method. Section 17 of this method describes the requirements for obtaining a waiver.
EssentialRegs notes
Our plain-English reading of Method 301. Not the method text.
What it measures
Whether a proposed alternative measurement method gives results with acceptable bias and precision for a pollutant in a given source or waste medium.
How it works
The candidate method is tested in the field alongside a reference method or with a known amount of the pollutant added to the sample, so its results can be compared with a known or accepted value. Statistical tests on those paired results determine the method's bias and precision. When bias is found, the method specifies how results can be corrected.
Equipment
No dedicated instrument. The equipment is whatever the candidate method and the reference method or spiking procedure require, together with a written validation protocol.
When a rule cites it
Requests to use an alternative or newly developed test method for a hazardous air pollutant when no promulgated method fits the source. Rules that allow an alternative method only after it is validated refer to this procedure.
Notes for compliance staff
Method 301 is a validation procedure, not a method for measuring a pollutant. The agency that approves the alternative method decides whether the validation data are accepted.
Cited by
Provisions in the corpus whose text cites Method 301. Subscribers land on the provision in the regulation reader; visitors see a preview of it (the GP05 sample opens in full).
Regulation 4
Regulation 8
- V.G.
- Appendix A — (for Part D)
40 CFR Part 60 Subpart OOOOb
40 CFR Part 60 Subpart OOOOc
The sections marked as regulatory text above are reproduced from the CFR. Everything under ‘EssentialRegs notes’ is our reference copy, not the method. The method as published in the CFR controls.