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Standard Interpretation



SIR #: 181
Standard: 2009 TNI
Section: V1M1, Section 4.2.1 (a)


REQUEST:

Please clarify the use of "analysis date" in V1M1, section 4.2.1 a) for successive PT samples. The standard states that the analysis date is to be at least 5 months apart and no longer than 7 months apart. TNI defines "analysis date" as the "calendar date of analysis" in the "Terms and Definitions" section. So, if a PT sample is analyzed on March 15, 2011, is the period anytime between August 2011 and October 2011 (5 - 7 months) acceptable, or, must one use the period August 15, 2011 to October 15, 2011 for the next PT sample?

TNI FINAL RESPONSE:

(PT Expert Committee and NELAP AC, 2-24-14)

The term "analysis date" is as defined in the Terms and Definitions. The 5 to 7 month window would be as is described above; PTs must be analyzed between August 15, 2011 to October 15, 2011 for evaluation purposes.