electrical and hydrogen lines

[Davebones]

We have a hydrogen fed annealing oven that has 2 valves that shut off the gas to the oven.These are about 1 foot from a electrical (200 amp) fusible disconnect.I have been asked if there is a clearance issue here and honestly I can't give a direct answer.Any information or thought would be appreciated.

 

[charlie]

. . . These are about 1 foot from a electrical (200 amp) fusible disconnect . . . is a clearance issue . . .

I don't know if this falls under the requirements of NFPA 54 or not. The Fuel Gas Code requires 3 ft of clearance but only from regulators and other places where the gas could leak. In my opinion, piping, valves, and the like are not places where the gas would leak and no clearance requirements apply except for 110.26.

 

[whillis]

In my opinion the disconnect would be in a Class 1 Division 2 location by proximity, but take that with a grain of salt because I have no idea what the environmental conditions are.

 

[rbalex]

NFPA 54 specifically excludes hydrogen systems from its Scope. Apparently all the old ?50 Series? of hydrogen Standards have been withdrawn in favor of a single new ?Hydrogen Technologies? Standard, NFPA 2 which has yet to be issued.

That being said, assuming the OP hydrogen piping system is properly designed, installed and maintained, the only concern I might have is the valves. I probably wouldn?t be too concerned about them either if the pressure and flow rates were low enough.