mowermech wrote:
I didn't check the listings, but I bet nearly all of the propane restricted tunnels are on the East Coast. Since I have no intention of going back there, no problem.
The only things I know of out here with propane restrictions are Washington State Ferries, and I won't take the motorhome on one of those anyway. Too expensive for me, I will drive around or park the motorhome and take the toad across.
Propane restricted tunnels are usually the ones where the middle is lower than the entrances (those that dip down rather than rise up). The reasoning is that propane is heavier than air and tends to collect hazardously in the middle of the tunnel. If the tunnel is crowned, any propane that leaks just works its way rather harmlessly to the tunnel exits and dissipates.
In practical terms, this means that tunnels that mainly go under things (cities or bodies of water, typically) very often restrict or prohibit propane, while tunnels that go through the middle of things (mountains) quite often do not. There are other advantages to having the middle of the tunnel higher than the endpoints, such as not having to worry about water pooling, so it's more common to design it that way if it's physically possible. It's only an East vs. West thing in as much as there are a good many tunnels under various bodies of water in the East but not so many in the West.
