Thanks Greg,  this is good info to know.  Thanks.

James

>
>As a firefighter, maybe I can shed some light.  When we respond to a car on
>fire call, the last thing we are worried about is an explosion from fuel
>tanks.  The reason is actually pretty simple.
>
>Gasoline in liquid form doesn't burn.  The danger is from the vapors that are
>given off from the gasoline as the temparture increases rapidly.   Diesel
>fuel is extremely safe in liquid form.  If the temperature of the fuel (gas
>or diesel) is low, there is little danger of explosion.  If the temp is high
>(like summer), the liquid can turn to vapor VERY quickly (as in miliseconds).
> The burn is expansive and so quick that it appears instant (hence an
>explosion).  The reason gas tanks don't explode very often is because even if
>the fuel gives off vapors and is ignited, there is little vapors to explode.
>
>The propane tank, as you indicated, has a over pressure relieve valve.
> Again, propane has to turn to vapor before it will ignite.  So LP propane
>has to expand to create vapors (and generate heat as well).  The
>characteristics of Propane igniting in an approved propane tank are rather
>complex and would take a long time to explain.
>
>The biggest threat to a person around a car fire is with the newer cars and
>the gas shocks in the bumpers and suspension shock absorbers..  Vanagons
>don't have these (at least through 85 anyway).
>
>Gregg Carlen
>85 Pierce Fire Engine (on occasion)
>85 Westy, 76 Goldwing, 51 Plymouth, 75 Mercedes, 69 Alcort...need more toys!