Boiler means any closed vessel exceeding 22.75 liters in
capacity and which is used expressively for generating steam under
pressure external to (outside) the boiler
and includes any mounting or other fitting attached to such vessel, which is
wholly or partly under pressure when the steam is shut off.
Steam Pipe means any pipe through which steam passes from a
boiler to a prime mover, or other user or both, if pressure at which steam
passes through such pipe exceeds 3.5 kg/cm2 above at. pr. or such
pipe exceeds 254 mm in ID and includes in either case any connected fitting of
a steam pipe.