The exhaust pipe from internal combustion engines shall be constructed in accordance with NFPA 211, NFPA 37, and based on the temperature of the gases entering the exhaust pipe, and in accordance with the following:
- The exhaust pipe, if factory fabricated, shall be installed in accordance with its listing and manufacturer's instructions.
- The exhaust pipe, if field fabricated, shall be constructed of at least 3/16-inch (5 mm) steel, or of other equivalent metal of similar strength and resistance to the temperature and corrosive action of the exhaust gases. No lining shall be required.
- Where the exhaust pipe runs inside a building, it shall be insulated with insulation adequate for the temperature of the pipe, so that the surface temperature shall be not more than 200°F (93°C).
- Where the exhaust pipe runs inside a building outside of the room containing the equipment, it shall be enclosed in fire-rated construction with a fire rating equal to the fire rating of the construction of the room.
- All joints shall be constructed so as to be gas tight under all operating conditions and tested in accordance with Section 810.