In general, OSHA expects that all flammable/combustible liquids be stored in either a flammable liquids storage cabinet, inside storage room, or warehouse. If the material in the aerosol cans is indeed flammable or combustible by the definitions found at 1910.106(b), then they must be properly stored.
There is an exemption for incidental storage that OSHA details at 1910.106(e)(2)(i) which allows storage of up to 25 gallons of Category 1 and 120 gallons of Categories 2, 3, and 4 in containers in any one “fire area” of a facility outside of flammable storage cabinet, storage room, or warehouse. Fire codes may dictate how quantities are stored. For instance, the fire code may require that aerosols be stored in a chain link or wire cage to protect against “rocketing” in case of fire.
Be aware that an employer’s liability insurance carrier may have specific storage requirements.