Retest date
The date a material must be re-tested to stay usable — not the date it becomes waste.
What is a retest date?
A retest date is the date by which a material should be tested again to confirm it still meets its specification. It differs from an expiry date in what happens when it passes. An expiry date is terminal: after it, the material is no longer considered fit for its intended use. A retest date is a checkpoint: the material is tested against its original specification, and if it still conforms it can be released for use again, usually with a new retest date assigned. Retest dating is common for stable raw materials and active ingredients whose degradation is slow and measurable, while expiry dating is used for finished products and for materials that degrade in ways routine testing cannot easily confirm. The distinction matters commercially, because surplus material past its retest date is frequently still usable, whereas material past a true expiry date generally is not.
How Surply uses it
Listings carry the expiry or retest date as the seller holds it, stated as whichever the manufacturer assigned rather than converted into the other. Surply does not re-date material and does not present a passed retest date as an expiry.
Also known as: retest date vs expiry date, re-test date, expiry date, shelf life.