Variance to be classified as a boiler

In accordance with the standards and criteria in section 33.1-24-01-04 (definition of "boiler"), and the procedures in section 33.1-24-01-12, the department may determine on a case-by-case basis that certain enclosed devices using controlled flame combustion are boilers, even though they do not otherwise meet the definition of boiler contained in section 33.1-24-01-04, after considering the following criteria: 1. The extent to which the unit has provisions for recovering and exporting thermal energy in the form of steam, heated fluids, or heated gases; 2. The extent to which the combustion chamber and energy recovery equipment are of integral design; 3. The efficiency of energy recovery, calculated in terms of the recovered energy compared with the thermal value of the fuel; 4. The extent to which exported energy is utilized; 5. The extent to which the device is in common and customary use as a "boiler" functioning primarily to produce a steam, heated fluids, or heated gases; and 6. Other factors, as appropriate.