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Standard Interpretation

Standard: 2003 NELAC
Section: Appendix D.3.1(a)(2)
Link to relevant standard


Can the standard be interpreted to mean a sterility blank is not required every 10 samples, as implied in the last sentence of the section, if the funnels are single use? It is assumed that the point of running the blanks every 10 samples is to show proper rinsing technique for multi-use funnels.

Because the final sentence in this section begins with "In addition," and is displaced from the sentence that says, "For pre-sterilized single use funnels a sterility check shall be performed on one funnel per lot," it seems to add a requirement to filtration series using all types of funnels, but I do not believe that was the intent.


(Quality Systems Committee / NELAP Accreditation Council, x-x-10)

It was the intent of QS that single use funnels, provided they are only used once, would not require any additional sterility check beyond once per lot as written in the Standard.

However, if the method being followed has more stringent requirements, those requirements must be followed.