Liquefied Petroleum Gas (LPG)

What it is

Liquefied petroleum gas (LPG, CAS 68476-86-8) is a mixture of C3–C4 hydrocarbons — primarily propane and butane — stored as a liquid under pressure. In consumer aerosol products it serves as the propellant that carries the liquid formulation out of the can as a fine mist, then evaporates immediately upon contact with air.

At room temperature LPG is a gas, so it leaves no residue and contributes no film-forming chemistry to the product formula. The safety concern is physical: flammable, pressurized containers that must not be punctured, incinerated, or exposed to temperatures above 50°C (122°F). The aspiration toxicity (H304) classification applies to the liquid phase at high concentrations — it is relevant to ingestion scenarios, not to normal consumer aerosol use.

In the context of automotive glass cleaners and rain repellents, LPG is an inert delivery mechanism for the active cleaning and repellent chemistry. It does not affect the performance or safety profile of the cured film left on glass.