What is CNG

Compressed natural gas (CNG) is a fossil fuel substitute for gasoline (petrol), CNG is a environmentally clean alternative to pterol / diesel  and is much safer than other fuels  in the event of a spill (natural gas is lighter than air, and disperses quickly when released). CNG is made by compressing natural gas (which is mainly composed of methane [CH4]). CNG produces 80% less carbon monoxide and 45% less hydrocarbons compared to gasoline and diesel.
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Owners of CNG converted vehicles also enjoy savings in maintenance costs since CNG is a clean-burning fuel and cause minimal damage or accumulation of debris in the engine’s pipes and systems. Also, it does not react with metal so pipes and other components last longer. CNG has an octane rating of 130 resulting in efficiency advantage over other fuels in many aspects.

Safety –  It is stored in strong seamless containers at a pressure of 200 bar (2900 psi),CNG in any approved cylinder is highly safe.CNG cylinders are put through exhaustive and extreme tests which include firing bullets at the canister, roasting it over a roaring bonfire and impact tests in which a crane drops the cylinder at multiple impact points.  The rigorous manufacturing process backed with stringent testing norms make it safer than gasoline tanks containing a much more flammable and toxic substance.