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Standard Interpretation

Standard: 2009 TNI
Section: V1M2, Section 5.8.5 (a)


Question: Do labs have to uniquely identify sample containers when received at the lab?

The 2009 standard states: "The laboratory shall have a documented system for uniquely identifying samples to be tested, to ensure that there can be no confusion regarding the identity of such samples at any time. This system shall include identification for all samples, sub-samples, preservations, sample containers, tests, and subsequent extracts and/or digestates."

The 2003 standard stated the same but also added: "The laboratory shall assign a unique identification (ID) code to each sample container received in the laboratory. The use of container shape, size or other physical characteristic, such as amber glass, or purple top, is not an acceptable means of identifying the sample."

Since the 2009 standard dropped the wording above in the third paragraph, some are interpreting this to mean the labs do not need to uniquely identify sample containers anymore. However, since the 2009 standard does still include sample containers in the last sentence of the second paragraph, above, some are interpreting that sample containers must be uniquely identified.

I have heard this may be addressed in the upcoming standard, but I don't know that absolutely.


The laboratory shall assign a unique identifier to each sample received. The laboratory shall use a system for recording how it uniquely identifies multiple containers of the same sample. The system must be able to identify the sample container from which the analytical result was obtained.