Aerosols are made up of two components:

1. The product; in the form of a liquid, emulsion or suspension.

2. The propellant; which can be a liquefied gas, or even a compressed gas.


The propellant is the driving force (or, you could say, the 'engine') behind the aerosol and there are two types:
(a) Liquefied propellants or
(b) Compressed gas propellants

Aerosol propellant grade LPG consists of a high purity mixture of propane, isobutane and n-butane. LPG is used as the propellant in most aerosols today.