LPG and CNG

[J.H. Crawford]

>My information is that since LPG is heavier than air and
>therefore forms a pool when it leaks, it is more dangerous
>than CNG.

LPG (propane) is a fair bit denser than air. It causes
explosions when it gets into the holds of pleasure boats

LNG (methane) is less dense than air and so tends to rise. 
Under most circumstances this leads to safe dispersion.
CNG, however, is a greenhouse gas and should not be
permitted to escape unnecessarily into the atmosphere.


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J.H. Crawford                                                 Carfree Cities
postmaster at carfree.com                                http://www.carfree.com