Compressed natural gas, CNG, is a form of natural gas that has been compressed to less than one percent of its volume at standard atmospheric pressure. In being natural gas, CNG contains the same properties: non-toxic, odorless, colorless, tasteless and lighter than air.
Under the Energy Policy Act of 1992, CNG is considered an alternative fuel. It is sold in units of gasoline or diesel gallon equivalents based on the energy content of a gallon of gasoline or diesel fuel. CNG is typically stored in tanks at a pressure of 3,000 to 3,600 pounds per square inch. Compressed natural gas has long been used to power natural gas vehicles, proving itself as an extremely safe and reliable alternative fuel.