[HartleyMBaldwin]

Natural gas is lighter than air.

[woodbutcher1963]

NG is lighter than air. Propane is Heavier.

Which is why it is so dangerous when there is a leak in a commercial building.

I recall a story years ago about a propane tank leak at some warehouse overnight in Buffalo, NY. When the fire truck showed up it leveled the city block and blew the fire truck hundreds of feet away. Destroying the warehouse, the fire truck and killing the firemen.

[Tell It Right]

Natural gas is lighter than air.

Good point. But carbon monoxide is heavier than most air and odorless.

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Deep thoughts, by Jack Handey.

[ro_dreaming]

Propane is not, which is what he referred to with the methyl mercaptan. It’s added to propane as propane is odorless natually.

[Elsie]

So are farts - or we’d almost never smell them.