Article 9: Combustion Air

§ 27-807 Air supply.

   (a)   Oil fuels. The air supply for equipment burning fuel oil shall comply with the requirements in applicable standards in reference standard RS-14. Ventilation shall be capable of providing at least thirty-six cfm of air for each gallon of oil per hour required to fire the equipment to gross output.

   (b)   Gas fuels. The air supply for equipment burning gas shall comply with the requirements of article sixteen of this subchapter.

   (c)   Solid fuels. The air supply for equipment burning solid fuels shall comply with those required for burning fuel oil based on Btu equivalent of the solid fuel.

   (d)   Mechanical ventilation. If the ventilation for the purpose of combustion is supplied mechanically, the ventilating system shall be electrically interlocked with the burner so that when the burner is in operation, the ventilating system shall maintain the room in which the equipment is located at a pressure not less than the outdoor atmospheric pressure.

§ 27-808 Flue dampers.

Dampers in flues shall be constructed so that they cannot completely cut off the passage of flue gases at any time. Tight-closing dampers may be installed with approved automatic draft and combustion controls.

Article 10: Piping Containing Steam, Hot Water or Other Fluids

§ 27-809 Insulation and clearances.

All accessible piping in habitable and occupiable rooms carrying steam, water, or other fluids at temperatures exceeding one hundred sixty-five degrees Fahrenheit shall be insulated to prevent the temperature at the outer surface of the insulation from exceeding sixty degrees Fahrenheit above the ambient temperature. The openings for insulated piping through combustible floors, walls, partitions, ceilings and other combustible construction shall include clearance and insulation adequate to satisfy the requirements of section 27-792 of article one of this subchapter. Where accessible piping carries a fluid not exceeding two hundred fifty degrees Fahrenheit and insulation would interfere with the functioning of the system, such piping may be uninsulated provided sufficient clearance is maintained from the combustible construction so that the temperature limitation of section 27-792 of article one of this subchapter is not exceeded, and all uninsulated piping shall be provided with at least one-half inch clearance from combustible materials.

§ 27-810 Firestopping.

For requirements governing firestopping around piping passing through floors, roofs, or fire separations, see subchapter five of this chapter.

§ 27-811 Insulation materials.

All insulations shall be of noncombustible materials. All coverings, vapor barriers and adhesives shall have a flame spread rating no higher than twenty-five and a smoke developed rating no higher than fifty. Adhesives and mastic finishes shall be tested in sufficient bulk to produce maximum burning, and shall be tested in accordance with reference standard RS 14-11.