(a) Boilers and pressure vessels, other than water heaters, shall be provided with a pressure indicating gauge which is visible to the operator on the floor or normal work platform.

(b) Pressure gauges shall have a pressure range of not less than 1 times the operating pressure, nor more than four times the operating pressure, except that steam heating boilers shall have an upper limit of not less than 30 psig nor more than 60 psig, and a dial travel of three inches between 0 psig and 30 psig.

(c) Hot water storage vessels and expansion tanks in boiler systems need not be provided with a pressure gauge in addition to the gauge supplied on the boiler.

(d) Steam boilers shall be provided with a syphon or equivalent which will provide a water seal and protect the gauge from being damaged by the steam.

(e) Pressure vessels, other than those used as air compressor receiver tanks, may have a remotely located pressure indicating device or a system pressure monitoring device in lieu of a pressure gauge connected directly to the pressure vessel.


History Note: Authority G.S. 95‑69.11; 95‑69.14;

Eff. January 1, 1995;

Amended Eff. July 1, 2006.