On Fri, 22 Aug 2008 14:27:29 -0700, Chris De Young
> wrote:

>Natural gas is lighter than air, and
>mixes with it readily, so leaks dissipate relatively easily. Propane is heavier
>than air and doesn't mix as easily, so it tends to pool in low places - bigger
>hazard.

So what do you consider worse...blowing up your attic or blowing up
your basement? <vbg>