LPG will not burn; LPG has a higher ignition temperature (4500 C) than automotive diesel oil [(ADO) 3800 C] and gasoline (3000 C) but not as high as Natural Gas for Vehicles [(NGV) 7000 C). A much hotter source is therefore, required for ignition of both LPG and NGV when used as automotive fuel.

• LPG is stored as a liquid in its fuel container and develops an inherent vapour pressure which forces the liquid fuel to flow to a simple but effective fuel system.
• If the fuel-air ratio is outside its flammability range of 1.8% to 9.6%.
• NOTE: As a comparison the flammability range of acetylene is approximately 2.5%-8%. It is a gaseous fuel commonly used extensively in workshops and industrial sites - without mishaps - and yet it is potentially many times more hazardous than LPG.
• LPG has a distinctive odour (ethyl mercaptan) added to it. This enables leak detection at very low concentrations of down to 1/5 of the lower limit of flammability.
• In the case of leakage, LPG vapour, which is denser than air, mixes quickly with air to produce flammable vapours which collect in hollows or depressions in the vicinity of the leak. The presence of an LPG leak can be detected by the distinctive odour added to it.
• Whenever LPG odour can be smelt it is extremely important to turn off the services valve and remove or eliminate all ignition sources.
• Warning: Do not activate any ignition source by attending to start the engine or by turning any switch "ON” or "OFF". (Ignition, door and boot switches can be sources of ignition).
• If the vehicle is indoors – push or tow it to an open area away from opening in building and ignition sources – then permit any leaking or residual gas vapour to disperse. (LPG vapour can also be dispersed with high pressure water diffuse spray).
• Any vehicle which has an LPG leak or a suspected LPG leak should be inspected by an accredited or licensed LPG installer who will be able to test and repair the faulty system to restore it to a leak free condition.
• Ignition sources are many and varied. Some common sources are matches, cigarette lighter, welding, grinding and operation of electrical switches. Two often-overlooked ignition sources static electricity and pilot flame on domestic hot water systems. Become familiar with sources of ignition in your workshop of garage.