From an EHS perspective, I am not inclined to identify all the old chemicals in a lab because they are simply old, and perhaps expired. It's most effective to focus on minimizing hazards, by reducing abundance and size of inventory of hazardous materials. By focusing on hazard types, and using the arguments that Ralph and Harry have highlighted, owners have very little impetus to keep old chemicals around. The pitch I like to make when there is some resistance to inventory minimization is: "You have four 2.5 L bottles of acetic acid that are at least 20 years old. Would you consider disposing of all of them if I replace them with one new 500 mL bottle?" It's short money for significant hazard avoidance.

In Hannah's case, sort your inventory list by NFPA rating if possible, and look for multiple containers of the same substance. If there are duplicates of old chemicals, then they are good candidates for disposal. Reduce inventory of unstable or highly reactive materials including peroxide formers. Reduce inventory of old aqueous solutions including acids and bases that nobody will use anymore because of quality concerns. Reduce inventory of old highly toxic materials. Purge hygroscopic chemicals that have become hydrated over time like trichloroacetic acid.

Andy Glode

From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**med.cornell.edu]On Behalf Of Harry J. Elston
Sent: Monday, August 01, 2016 9:10 PM
To: DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU
Subject: Re: [DCHAS-L] Chemical Inventory