NAC455C.274. Supervision.

     1. Except as otherwise provided in subsection 4, a high-pressure, high-temperature water boiler and a power boiler must be attended by an operator who meets the qualifications set forth in NAC 455C.268.

     2. The operator shall personally check the operation of the boiler, the necessary auxiliaries and the level of water in the boiler at intervals necessary to ensure the boiler’s safe operation. The boiler and its auxiliaries must be checked at least once every 60 minutes and must not be left unattended for periods in excess of the time required to evaporate the water from the normal operating level to the lowest water level permissible if the feed water is shut off or the boiler is forced to its maximum capacity. A log noting the time of all checks and observations must be kept in the boiler room.

     3. If the attendance of the boiler is required pursuant to this section, a clock to start or stop automatically the operation of the boiler must not be used, unless the timing mechanism is a device or system which has been approved by the Enforcement Section.

     4. High-pressure, high-temperature water boilers and power boilers are not required to be attended, if the boiler is equipped with the following functioning protective devices, as required by the applicable provisions of Controls and Safety Devices for Automatically Fired Boilers, as adopted by reference in NAC 455C.108:

     (a) If the boiler is operated at less than supercritical pressure:

          (1) A low water fuel cutoff;

          (2) An automatic feed regulator;

          (3) Fireside regulators and controls;

          (4) An audible alarm to indicate low water;

          (5) A pressure control; and

          (6) A programmed flame safeguard system with an audible alarm on burners equipped with spark ignition.

     (b) If the boiler is operated at supercritical pressure, it must include all the devices described in paragraph (a) and:

          (1) A cutoff device for high temperature or fuel; and

          (2) An audible alarm to indicate high temperature.

     5. As used in this section, “supercritical pressure” means 3,206 pounds of pressure per square inch at 705 degrees Fahrenheit.

     (Added to NAC by Div. of Industrial Relations by R101-02, eff. 12-15-2004)