Most aerosol cans contain hydrocarbon propellant, although hydrocarbons are less harmful than HCFCs & CFCs, they are highly inflammable. If sprayed near a fire, this hydrocarbon propellant becomes a fire hazard. That is why it is recommended that can recycling system like the Newstripe AeroVent aerosol can recycling system should be used to safely depressurize the aerosol can before disposal.