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Standard Interpretation

Standard: 2009 TNI
Section: V1M2, Section 5.4.2


I wanted to get a clarification on the requirements from V1M2, Section 5.4.2 Selection of Methods.

5.4.2 includes the following statement: "The laboratory shall ensure that it uses the latest valid edition of a standard unless it is not appropriate or possible to do so."

In general, it seems that most certification authorities certify for the method, but not the version, allowing any version that is still valid to be run, which seems to violate/contradict this statement.

Does this statement mean that all previous valid method versions are NOT to be used and that the lab MUST update to the newest version of a standard? For example, if the lab runs EPA 8270C which is still valid, must the lab update to 8270D if it can? In other words, does running 8270C (when 8270D is the latest version) become a violation of the standard?

I look forward to your response/clarification.


(Quality System Expert Committee and NELAP AC, 10-4-14)

The term "Standard", as defined by ISO, is as follows: "Standard: document, established by consensus and approved by a recognized body, that provides, for common and repeated use, rules, guidelines or characteristics for activities or their results, aimed at the achievement of the optimum degree of order in a given context.

NOTE - Standards should be based on the consolidated results of science, technology and experience, and aimed at the promotion of optimum community benefits."

"Standard" refers to the source document or publication that mandates the "approved test method." For laboratories, this use of the term "standard" in V1M2 Section 5.4.2 is a reference to the most current publication(s) that define or require certain methods/actions based on program or regulatory need, such as:

- International (global documents),
- Regional (i.e., requirements specific to State, local, EPA Region, etc.), or
- National (i.e., requirements by Federal Regulation/Agency via the Code of Federal Regulations (CFR).

Additional analytical requirements can be listed in/by reputable technical organizations (i.e., AOAC, AIHA, etc.), scientific texts/journals and manufacturers (i.e., instrument specific, process requirements, etc.).

Analytical methods ("test methods" in the ISO language) used by the environmental laboratory industry are driven by regulations where governing programs exist. The "standard" that mandates the required methods for EPA programs is the US CFR Title 40 (40 CFR.) Where programs are federally regulated, laboratories shall use the most current CFR to determine method requirements by specific program. Methods found in "Test Methods for Evaluating Solid Waste, Physical/Chemical Methods" (SW-846) are to be used "as published" by the EPA and do not go through a formal promulgation process. Individual state and program requirements may exist that mandate one version of a method over another, such as Method 8270D vs 8720C, therefore requirements by project, accreditation body, and state/local/regional agency must be considered.