Peroxidizable chemicals can react with ambient air to form peroxides if they are stored for long periods of time. Peroxides, if not handled properly, can explode with impact, heat, or friction.

Date peroxide-forming chemicals when you receive/open the container and dispose of the chemical if stored beyond expiration to prevent peroxide formation. Do not open any container that has solid formation around the lid. Neglected peroxide-forming chemicals can cause them to crystallize. The crystals are highly explosive when aggravated. EHS will remove any peroxides stored beyond expiration.

Some peroxide-forming chemicals that may be found in the lab include:

Common findings related to peroxide-forming chemicals:

Undated peroxide formers identified: 

Peroxide-forming chemicals must be labeled once with the date of receipt and again with the date, the material is opened. All peroxide-forming chemicals must be discarded six months after opening or by the expiration date, whichever occurs first.

Expired peroxide forming chemicals: 

Expired peroxide-forming chemicals may form very sensitive explosive material and must be removed from the lab immediately by trained personnel. NEVER handle expired containers or test chemicals for peroxides within the lab; Request removal by EHS.