Cylinders transported to, from or within the United States must be manufactured, inspected and tested in accordance with the applicable specifications given in 49 CFR 178, except that foreign cylinders received in the United States for charging may be transported for purposes of export from the United States in accordance with 49 CFR 171.23(a)(4). Portable tanks other than UN portable tanks manufactured outside the United States that meet the applicable requirements of the UN Model Regulations must be designed and approved in accordance with the requirements of 49 CFR 178.270 through 178.272.
Except as provided in 49 CFR 173.306, aerosol containers larger than 120 millilitres capacity (four fluid ounces) must be non-refillable metal or plastic aerosols. Aerosols must consist of a gas compressed, liquefied or dissolved under pressure, with the sole purpose of expelling a nonpoisonous (other than a Division 6.1 Packing Group III material) liquid, paste or powder and fitted with a self-closing release device allowing contents to be ejected by the gas.