Ask the Expert Question-and-Answer Archive

by Ron Joseph

August, 2004

Recertification and Qualification of Paints

Q. There seems to be a lot of questions on the validity of re-qualification or re-certification of shelf life expired opened containers of paint or its components. Recognizing opened (then re closed) containers may significantly reduce shelf life, and discarding the specifications that address open and/or partial containers (ie MIL-P-23377, where thou shall discard open containers after 14 days), where the paint specification is silent about it, and a sample is submitted to the manufacturer and the test results meet the specification requirements, wouldn't that logically allow the re-cert of opened containers? Is there an ASTM spec that addresses this? Is there an industry accepted practice? The specific paint system I'm working with is MIL-C-46168. Thank you in advance.

Thanks for your question. I don't have a definitive answer for you and also do not know of an ASTM spec that addresses recertification of opened containers.

When I worked for a large military contracting company we took the paint and conducted in-house laboratory tests on samples to determine if there had been any degradation of the properties. If the samples passed all of the tests, we used the paint rather than discard it.

Since you are specifically referring to MIL-C-46168, you might want to write to the Army Research Lab at the Aberdeen Proving Grounds, MD. This lab is the custodian of the specification.

If you get an answer, can you please write back to me and tell me what you found out?

Best wishes,

Ron Joseph