If the aerosol can originally contained a substance that could be regulated as a hazardous waste, then the can itself is also a hazardous waste unless it can be drained or emptied to less than 3% by weight of the total capacity of the container(40 CFR 261.7(b)(1)(1) & (111)). The hazardous waste code is determined by the contents of the can.

An aerosol can that has been emptied but not punctured and drained will most likely contain propellant even when less than 3% by weight of the total capacity remains in the container.   Aerosol cans containing propellant are hazardous waste because the propellant makes the can reactive (Waste Code DOO3) when in contact with a strong initiating force (i.e. intense pressure or heat). Therefore, unless the aerosol cans can be completely emptied of propellant by puncturing and draining, the cans are classified as a hazardous waste, regardless of the quantity of substance remaining in the can.

On-site Storage of Waste Aerosol Cans

Aerosol cans that have been declared a waste should be stored in a properly designated satellite or or 90/180/270 day accumulation area depending on the generators size classification.

Disposal

An aerosol can that has been both punctured and drained of its contents meets the definition of scrap metal (40 CFR 261.1(c)(6)), and if recycled, is exempt from regulation under 40 CFR 261.6(a)(3)(iv). Scrap metal that is recycled is exempt from RCRA regulation under this provision even if it is hazardous waste (provided the can is empty), so generators need not make a hazardous waste determination.

Scrap metal that is not recycled, however, is subject to the hazardous waste regulations if it is hazardous, so generators must make a hazardous waste determination.

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