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Standard Interpretation

Standard: 2003 NELAC
Section: (c)
Link to relevant standard


Are microorganisms considered standards? Does the lab need to assign an expiration date on them? The reference cultures the lab receives from ATCC does not have expiration dates. The lab is following the protocol for microorganism listed in Appendix D3.7.


The ATCC reference cultures are "reference materials" and must adhere to the requirements of These requirements include the requirement of having an expiration date whether supplied by the vendor or assigned by the laboratory.