Just a quick mention here of the fast, new, but still memorably named Fisher N863 Snappy Joe Emergency Shutoff Railcar Valve (pdf). You see, for the past three decades or so, there’s only been one such valve designed especially for loading and unloading propane from railcars — Emerson’s Fisher Snappy Joe N562.
And to best suit a variety of compressed-gas applications, the new Snappy Joe N863 can come equipped with Nitrile, Neoprene, Kalrez™, Teflon™, Viton™, or EPDM valve seals.
It should be UL listed soon. Keep a lookout.