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Standard Interpretation

SIR #: 10005
Standard: 2009 TNI
Section: V1M2, Section 5.4.2


I am not sure what section, but my question refers to a statement that was made at a FSEA meeting October 27 - 29, 2010 at Palm Beach Gardens, Fl. A statement was made in reference to everyone must use the most recent version of Standard Methods. For clarification, I wanted to know if this is for the most recently EPA approved version of Standard Methods? Currently some EPA approved methods go as far back to the 18th ed. of Standard Methods.
Thank you for your time.

5.4.2 Selection of Methods (ISO/IEC 17025:2005(E), Clause 5.4.2)
The laboratory shall use test and/or calibration methods, including methods for sampling, which meet the needs of the customer and which are appropriate for the tests and/or calibrations it undertakes. Methods published in international, regional or national standards shall preferably be used. <em>The laboratory shall ensure that it uses the latest valid edition of a standard unless it is not appropriate or possible to do so.</em> When necessary, the standard shall be supplemented with additional details to ensure consistent application....
....The laboratory shall inform the customer when the method proposed by the customer is considered to be inappropriate or out of date.


The key is the <em>italicized</em> phrase from 5.4.2. The latest edition of a method must be used unless it is not appropriate or possible to do so. Therefore, if a method from an earlier edition of a published document (such as Standard Methods) is mandated for use by a regulatory agency, then it is not appropriate to use the most recent method.