Note: While EPA has finalized regulations including aerosol cans as a universal waste, Missouri is still evaluating this set of regulations and has not incorporated them by reference. Until that time aerosol cans will need to continue to be managed as “regular” hazardous waste.
Waste aerosol cans are a challenge for businesses to manage. A business may generate one or two cans on an infrequent basis or many as processes demand. All contents of the can (product, inert ingredients, propellants and gases) may or may not be identified on the label or Safety Data Sheet. Cans become waste when they are empty and product can no longer be expelled, or when the product has exceeded the useful shelf life. Sometimes cans become waste when the nozzle or valve fails or the contents begin to solidify. To minimize waste disposal problems, the Missouri Department of Natural Resources encourages businesses to:
- Purchase only what is required.
- Follow label directions to prevent clogging.
- Use the product within its useful shelf life.
- Purchase products without hazardous characteristics.
Aerosol cans and other wastes generated by households are exempt from hazardous waste regulation. This fact sheet and the associated decision tree for managing waste aerosol cans provide general information to help businesses manage their hazardous waste aerosol cans safely and legally. It is for general guidance only. Businesses should refer to the appropriate state and federal laws and regulations and to determine compliance. References: 40 CFR 261.7 and 10 CSR 25-5.262(l) incorporating 40 CFR 262.11.
Waste Management Options
Empty aerosol cans that are recycled as scrap metal are exempt from most hazardous waste regulations [40 CFR 261.6(a)(3)(iii)]. Non-empty aerosol cans should only be sent to a recycler or punctured in a unit at a facility capable of managing pressurized containers and associated vented liquids, gases and propellants.
Improper depressurization of aerosol cans is extremely dangerous, and the release of hazardous material may violate the Missouri Hazardous Waste Management Law or the Clean Air Act. If aerosol cans are destined for scrap metal recycling, the process of emptying the cans is considered part of the recycling process and a hazardous waste treatment permit is not required for this activity. However, any liquids or gases removed from the cans are solid wastes if they cannot be used for their intended purpose. If unusable, the collected residues must be evaluated to determine if they are hazardous waste (40 CFR 262.11). If the contents are hazardous waste, they are subject to all applicable hazardous waste regulations regarding on-site management, transportation, treatment and disposal.
Department of Transportation regulations may apply to the transportation of some cans as hazardous material. If the contents of some cans are hazardous and the contents of others are not, the bulking and commingling of the contents are not considered illegal dilution. However, bulked contents must be evaluated for use, recycling or disposal as described above.
Satellite Accumulation of Spent Cans
Spent aerosol cans may be kept in satellite accumulation areas following the satellite accumulation storage regulations. Currently there are two options for satellite accumulation management. Information on these options
and Management of satellite accumulation areas can be found in the publication Hazardous Waste Satellite Accumulation - PUB 2215.
For all aerosol cans, use as much of the can’s contents as possible for the intended purpose. For the can to be empty, the pressure of the propellant gas should be unable to propel any more material from the can. (Note: If the nozzle or valve malfunctions, and some of the contents remain, the can is not empty.)
If the can is empty of all liquids, gases and propellants, it may be recycled or disposed in a sanitary landfill. Recycling as scrap metal is strongly encouraged. If the can is not empty, a generator must perform a hazardous waste determination on both the can and any residuals remaining in the can (liquids, gases or propellants). If the can or the contents are hazardous waste, it must be managed under all applicable regulations including transport, treatment and disposal as a hazardous waste.
Since aerosol cans containing acutely toxic materials, including those that are P-listed or U-listed (such as certain types of pesticides) cannot be triple rinsed, disposal may be the only option. Although the venting of an aerosol can is not considered treatment, the captured liquids, gases or propellants may be subject to hazardous waste regulations if they cannot be used or reused without any additional processing or treatment. As previously noted, the characteristics of any unusable residues must be identified and if hazardous, transported, treated and disposed of according to all applicable regulations.