Glossary
Retest date
The date when a material should be re-examined to confirm it is still suitable for use. Unlike an expiry date, a passed retest date does not condemn the batch; it means use should wait for a fresh, representative retest.
Why it matters on a certificate
APIs commonly carry retest dates rather than expiry dates, and the difference changes what a buyer may do when the date passes. A certificate reviewed months after issue may describe a batch whose retest date has since lapsed: the results remain true of the batch as tested, but they no longer speak for the batch as it is now.
A worked example
Stock bought in January carries a certificate with a retest date that passed in June. Before the material is used in July, a representative sample is retested against the specification; the original certificate alone cannot carry the decision.
Examples are synthetic and illustrative; any limits shown are not the requirements for any particular material.
The COA Validator checks the element this term describes on every certificate it reads, and reports what is present, what is missing and what does not add up.