All reagents, solutions, etc. used in our laboratory must have labels containing preparation dates and expiration dates. Does anyone have a suggestion as to what would be an appropriate lengh of time for an expiration date for pure solvents (i.e. isopropanol) poured from their original containers into LC pump reservoir bottles. These solvents are only used periodically to perform manitenance procedures and performance qualification testing and don't come under any existing SOP.

Our lab has the same labelling requirements so we give pure solvents for maintenance a week (the shortest mp expiry)and degas on day of use.
If the solvents are only used periodically then use fresh every time and label exp and prep date as the same day then just dispose of them at the end of the day.