In Minnesota, generators can puncture waste aerosols or gas cylinders that have been shown to be empty or that have been evaluated as non-hazardous, as long as any unavoidable liquid residuals are collected and properly managed.
However, hazardous waste aerosols and gas cylinders may no longer be punctured or vented in Minnesota after January 1, 2017, unless all hazardous waste propellant gases, product gases, and liquids are captured and properly disposed. MPCA does not allow charcoal and activated carbon filters to be used to capture hazardous waste propellants or gases for disposal.
The deliberate release of hazardous waste propellant or compressed gas to the atmosphere has been prohibited by the Minnesota Hazardous Waste Rules for many years, but MPCA chose not to enforce this prohibition. This allowed generators and collection sites to puncture hazardous waste aerosols and dispose of ignitable hazardous waste to the atmosphere. This practice is not allowed after 1/1/2017.
UPDATE: The compliance deadline For this change to enforcement policy has been updated.