It is recommended that all boilers operated with gas, oil, or mechanical firing be provided with an automatic low water fuel cutout and/or with an automatic fuel regulating governor controlled by the steam pressure. Such a governor used on gas fuel shall be so constructed that in the event of its failure there can be no possibility of steam from the boiler entering the gas chamber or supply pipe.
N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 14-11.12