Par. 1. - Drain and connecting ventilation pipes, vents and back air pipes shall be of sufficient size, and made of extra heavy cast iron pipe if under ground, and if above ground shall be made of extra heavy cast iron, galvanized wrought iron of standard weight, or of not less than number thirteen Stubbs gauge brass pipe within the building, except that lead pipes may be used for short connections exposed to view. Cast iron drains shall extend not less than ten feet from the inside face of the wall, beyond and away from the building.

Par. 2. - Drain pipes above ground shall be secured by iron to walls, suspended from floor timbers by strong iron hangers, or supported on brick piers. Proper man-holes shall be supplied to reach clean-outs and traps. Every drain pipe shall have a fall of not less than one quarter inch per foot, and shall be extended from a point ten feet outside the inside face of the wall, unobstructed, to and through the roof, undiminished in size, and to a height not less than two feet above the roof, and not less than one foot above the top of any window within fifteen feet and not less than eight feet above the roof if the roof is used for drying clothes or as a roof garden. The drain pipe shall be supplied with a Y branch fitted with a brass clean-out or with an iron stopper, if required, on the direct run, at or near the point where the drain leaves the building. Changes in direction shall be made with curved pipes, and all connections with horizontal or vertical pipes shall be made with Y branches. Saddle hubs shall not be used. All drain pipes shall be exposed to sight within the building, if such exposure is practicable, and shall not be exposed to pressure where they pass through the wall.

Steam Exhausts, Etc

Par. 3. - No steam, or vapor, or water of a temperature over one hundred and thirty degrees Fahrenheit shall be discharged from any premises into any sewer, drain or catch-basin, nor shall any matter or thing be discharged into any sewer which may tend to cause an obstruction of the public sewer or a nuisance or a deposit therein or any injury thereto.

Blow-Off Tanks

Par. 4. - All high pressure steam boilers shall be connected with a blow-off tank of a capacity not less than thirty per cent of the largest boiler connected with such tank. The location of and the connections to said blow-off tank shall be subject to the approval of the superintendent of sewers.

Steam Exhausts

Par. 5. - No steam exhaust or steam drip, unless it be provided with a cooling tank of a capacity approved by the superintendent of sewers, or unless it be connected with the blow-off tank, shall connect with any drain leading to the sewer. Every blow-off tank shall be supplied with a vapor pipe not less than two inches in diameter, which shall be carried above the roof and above the highest windows of the building.

Blow-Off Tanks. - Additional Requirements.

Par. 6. - The superintendent of sewers may require such additional means for cooling the blow-off tanks by the injection of cold water or otherwise as may be necessary to reduce the temperature of the water passing from the blow-off tank so that it shall not exceed one hundred and thirty degrees Fahrenheit.