.07 Gas-Fired Installations.

A. A burner in a gas-fired installation shall be tested and certified by the American Gas Association.

B. A gas-fired boiler shall have a vent or flue that terminates at an acceptable location outside the building.

C. The size of the vent or flue shall be:

(1) That recommended by the boiler manufacturer;

(2) At least 4 inches in diameter or equivalent area; and

(3) If the horizontal run exceeds 10 feet, at least 6 inches in diameter or equivalent area.