HAR §12-222.1-7. discrete systems that continuously measure, transmit, and display water level) may be provided

In addition, minimum water levels shall be clearly marked; (iii) When both remote level indicators are in reliable operation, the remaining gage glass may be shut off, but shall be maintained in serviceable condition; and (iv) When the water level in at least one gage glass is not readily visible to the operator in the area where control actions are initiated, either a fiber optic cable (with no electrical modification of the optical signal) or mirrors shall be provided to transfer the optical image of the water level to the control area. Provided that alternatively any combination of either an independent remote water level indicator or an independent continuous transmission and display of an image of the water level in a gage glass may be used. If the latter is used, then the display of a remote water level indicator shall have a clearly marked minimum water level reference at least two (2) inches above the lowest permissible water level, as determined by the manufacturer; (9) Gage glass assemblies with multiple sections, whether of tubular or other construction, shall: (A) Ensure a one-foot overlap of all adjoining sections so the water level is visible; or (B) Ported or reflex gages using refractive light to aid determination of water level may omit the requirement of overlapping sections; (10) The gage class cock connections shall not be 222.1-22 3559 §12-222.1-7 less than one-half (1/2) of an inch NPS; (11) Each gage glass, externally mounted water level, or water level controlling device shall be fitted with a drain cock or valve having an unrestricted drain opening of not less than one-fourth (1/4) of an inch in diameter to facilitate cleaning; (12) Connections for gage glasses connected directly to the boiler or to an intervening water column shall be at least NPS one-half (1/2); (13) Connections from the boiler to a remote water level indicator shall be at least NPS three-fourths (3/4), including the isolation valve; and from there to the remote level indicator at least one-half (1/2) of an inch in OD tubing; (14) Water level connections shall be completely independent of other connections for any function other than water level indication; and (15) Electric steam boilers shall have at least one water-gage glass. On electrode type electric boilers, the gage glass shall be located as to indicate the water levels both at startup and maximum steam load conditions, as established by the boiler manufacturer. On resistance element type electric steam boilers, the lowest visible part of the gage glass shall be located at least 1 inch above the lowest permissible water level established by the boiler manufacturer. (b) Low-water fuel cutoffs and water feeding devices. The following shall apply to low-water fuel cutoffs and water feeding devices: (1) Each automatically fired steam or vapor system boiler shall have an automatic low-water fuel cutoff device so located as to automatically cut off the fuel supply when the surface of the water falls to the lowest visible part of the water-gage glass. If a water feeding device is installed, it shall 222.1-23 3559 §12-222.1-7 be so constructed that the water inlet valve cannot feed water into the boiler through the float chamber and so located as to supply requisite feedwater; provided that such a fuel cutoff or water feeding device may be attached directly to the boiler. A fuel cutoff or water feeding device may also be installed in the tapped openings available for attaching a water glass directly to the boiler, provided the connections are made to the boiler with nonferrous tees or Ys not less than NPS one-half (1/2) inch between the boiler and water glass so that the water glass is attached directly and as close as possible to the boiler, the run of the tee or Y shall take the water glass fittings, and the side outlet or branch of the tee or Y shall take the fuel cutoff or water feeding device. The ends of all nipples shall be reamed to full-size diameter. In addition, a secondary low-water fuel cutoff with manual reset shall be provided on each automatically fired steam or vapor system boiler; (2) Functioning of the lower of the two controls shall cause safety shutdown and lockout. The manual reset may be incorporated in the lower cutoff control. Where a reset device is separate from the low-water fuel cutoff, a means shall be provided to indicate actuation of the low-water fuel cutoff. The manual reset device may be of the instantaneous type or may include a time delay of not more than three (3) minutes after the fuel has been cut off; (3) The fuel cutoff device may be inserted internally or attached externally to the boiler. An external cutoff device may be attached on piping connecting a water column to the boiler or combined with a water column; (4) Water column piping and connections shall be at least NPS 1 (DN 25). If the low-water 222.1-24 3559