811.1 Exhaust system construction.
MC § 811.1
The exhaust system from internal combustion engines shall be constructed in accordance with NFPA 211, NFPA 37, and based on the temperature of the flue gas entering the exhaust system, and in accordance with the following: 1. The exhaust system, if factory built, shall be installed in accordance with its listing and manufacturer's instructions. 1.1. Exhaust systems with flue gas temperatures greater than 300°F (148.9°C) shall be listed to UL 103 or UL 2561 and be rated for a minimum of 60 inch w.c. (14 934.3 Pa). 1.2. Exhaust systems with flue gas temperatures not more than 300°F (148.9°C) and that are capable of causing excessive condensate production in the exhaust system shall be listed to UL 103 or UL 2561 and UL 1738 and be rated for a pressure suitable for the operating conditions.
2.The exhaust system, if field fabricated, shall be constructed of at least 3/16-inch (4.8 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.
3.Where the exhaust system runs inside a building, it shall be insulated adequately for the equipment operating temperature, so that the surface temperature shall be not more than 200°F (93.3°C).
4.Where the exhaust system 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.
5.All joints shall be constructed so as to be gas tight under all operating conditions and tested in accordance with Section 810.
