What is propane?
	Benefits
	Safety and performance
	Vehicle and fuel availability
	Links

Safety and performance

Safety

Propane has a good safety record as a transportation fuel, thanks to national and provincial/territorial standards for safety and handling that require staff training and certification of equipment installers and refuelling sites. Like gasoline, propane is highly combustible, but it has two safety advantages over gasoline: it must be present in higher concentrations in the air before it will ignite, and it requires a much higher temperature than gasoline to ignite.

In its liquid form, propane is colourless and non-toxic, but it will displace air and oxygen and can become an asphyxiant. An odorant is added to permit detection in the case of a leak. The odorant smells "skunky" or like a rotten egg. It is added in concentrations that can be noticeably smelled at one fifth of the lower combustion limit.

Refuelling a propane vehicle is relatively simple, but it is important to be aware of some safety precautions. The tank must be filled to only 80 percent of its capacity because liquid propane expands and contracts with changes in temperature. Conversions made before 1991 may not have automatic stop-fill valves in the vehicle tank.

Federal, provincial and territorial regulations spell out the safe design, manufacture, testing and installation of propane vehicles.

Vehicle performance

There is usually no significant difference in performance between propane and gasoline vehicles. Gasoline vehicles that are converted to propane with some after-market systems may experience a slight drop in the maximum horsepower of the vehicle under a wide-open throttle. This does not occur with liquid propane injection.

Propane is a naturally high-octane fuel (rated at 104). Manufacturers of propane vehicles can optimize the engine for propane by increasing its compression ratio, which improves thermal efficiency and leads to better fuel economy.

Propane-powered vehicles reportedly have less carbon build-up. Many fleets report a reduction in maintenance costs or an increase in the life of vehicles that operate on propane, but this is difficult to quantify.