Section 15. Back Pressure. For preventing back pressure all soil pipes shall be connected with the horizontal drains and all horizontal runs by long bends, and no running or other trap of any kind shall be permitted in the horizontal drains or between the house drain and the public sewer.

Section 16. Clogging. To prevent clogging the discharge of all fixtures shall be so constructed as to permit of the waste pipes being filled "full bore" after use and no trap shall be accepted which shall contain at any part a cesspool chamber having a sectional area measured at right angles with the flow of the water current through the trap of more than twice the sectional area of the inlet arm of the trap. Exception shall be made for grease or other special traps as provided in Section 32.

Section 17. A Single Trap for Several Fixtures. Several fixtures may be connected with one trap, provided the trap is not over five feet from the outlet from any fixture.

Section 18. Earthenware Traps shall have heavy metal floor plates secured to the trap flange, and the joint shall be made gas tight.

Section 19. Supports. Soil pipes or iron waste pipes shall be supported by clamps to the wood work, iron drive hooks to brick walls, or bolted clamps to iron girders.

Section 20. Chemical Laboratories. The installation of fixtures and waste pipes in chemical laboratories shall be constructed in accordance with plans approved by the Board of Health.

Section 21. Stable Fixtures. The drainage of stable fixtures shall be constructed according to plans approved by the Board of Health.

Section 22. Refrigerator Wastes and Drip Pipes. All drip or overflow pipes shall be extended to some place in open sight, and shall not be connected directly with the drain pipe, unless protected by an unvented antisiphon trap. No waste pipe from a refrigerator or other receptacle in which provisions are stored shall be directly connected with a drain or other waste pipe, unless protected by an unvented antisiphon trap.

Section 23. Pipes and Fittings. The diameters of soil and waste pipes shall not be less then those given in the following table:

Inches.

Soil pipes...........................................

4

Main waste pipes.......................

2

Main waste pipes for kitchen sinks on five or more floors.........................................

3

Branch waste pipes for laundry tubs............................

1

Branch waste for kitchen sinks........................

1

Branch waste for urinals............................

1

No branch waste for other fixtures shall be less than. ..................... .......................

1

Except that a three-inch soil pipe, with the approval of the commissioner may be used for one water-closet where it is not practicable to use four-inch pipe.

When brass ferrules are used they shall be best quality, bell-shaped, extra heavy cast brass, not less than four inches long, and not less than the following weights:

Diameters

Weights.

2

inches

.......................................................

1

pound

0

ounces.

3

inches

........................................................

1

pound

12

ounces.

4

inches

.......................................................

2

pounds

8

ounces.

One and one-half inch ferrules shall not be used.

Soldering nipples shall be of heavy cast brass or of brass pipe, iron-pipe size. If cast, they shall not be less than the following weights:

Diameters,

Weights.

1

inches

.......................................................

0

pounds

8

ounces.

2

inches

.......................................................

0

pounds

14

ounces.

2

inches

.......................................................

1

pound

6

ounces.

3

inches

.......................................................

2

pounds

0

ounces.

4

inches

.......................................................

3

pounds

8

ounces.

Section 24. Lead Pipes. All lead waste pipes shall be of best quality, known in commerce as "D," and of not less than the following weights per linear foot:

Diameters.

Linear Foot.

per Linear Foot.

1

inches

(for flush pipes only)...................

.2

pounds.

1

inches

.......................................................

3

pounds.

2

inches

.......................................................

4

pounds.

3

inches

.......................................................

6

pounds.

4 and 4

inches

.......................................................

8

pounds

Section 25. Brass Pipes. Brass pipes for soil, waste, vent and back air pipes shall be thoroughly annealed, seamless, drawn brass tubing of not less than number X Stubbs gauge.

Threaded connections on brass pipe shall be of the same size as pipe threads for same size of pipe and be tapered.

Section 26. Cast-Iron Pipe. Cast-iron pipe shall be uncoated, sound, cylindrical and smooth, free from cracks and other defects, of uniform thickness and of the weights shown in the following table. If buried under ground they shall be coated with asphaltum or red lead.

Pipe, including the hub, shall weigh not less than the following average weights in pounds per five foot lengths.*

If Hand Caulked Lead Hub and Spigot Joints are Used

If Machine

Made Rigid

Joints are Used

If

Flexible

Joints are Used

2

inches

............................................

27

20

17

3

inches

............................................

47

30

22

4

inches

............................................

65

45

32

5

inches

............................................

85

60

42

6

inches

............................................

100

75

52

7

inches

............................................

135

100

75

8

inches

............................................

170

125

85

10

inches

............................................

225

175

115

12

inches

............................................

270

165

Section 27. Wrought-Iron and Steel Pipes shall be not less than the average thickness and weight set forth in the following table:

Diameters

Thickness

Weights per Lineal Foot

1

inches

.14

inches

2.68

pounds

2

inches

.15

inches

3.61

pounds

2

inches

.20

inches

5.74

pounds

3

inches

.21

inches

7.54

pounds

3

inches

.22

inches

9.00

pounds

4

inches

.23

inches

10.66

pounds

4

inches

.24

inches

12.34

pounds

5

inches

.25

inches

14.60

pounds

6

inches

.28

inches

18.76

pounds

7

inches

.30

inches

23.27

pounds

8

inches

.32

inches

28.18

pounds

9

inche3

.34

inches

33.70

pounds

10

inches

.36

inches

40.06

pounds

11

inches

.37

inches

45.02

pounds

12

inches

.37

inches

48.98

pounds

*See Note on Page 694.

Threaded part of the pipe if less than one and one-half inches long, shall be of the thickness and weight known as "extra heavy" or "extra strong."

All wrought-iron pipe shall be equal in quality to "Standard," and must be properly tested by the manufacturer.

Fittings on wrought-iron vent pipes may be the ordinary cast or heavy malleable steam or water fittings. Fittings for "Plumber's tubing" shall be heavy weight, with sharp threads.

Fittings for waste or soil or refrigerator waste pipes of wrought-iron or brass pipe shall be smooth and sound cast-iron or brass, recessed and threaded drainage fittings, with smooth interior waterway and threads tapped, so as to give a uniform grade to branches of not less than one-quarter of an inch per foot. All fittings except cast-iron or brass fittings for wrought-iron pipes shall be galvanized.

All joints for wrought-iron or brass pipe shall be screwed joints made up with red lead, and the burr formed in cutting shall be carefully reamed out.

Section 28. Fixture. Waste Outlets to be large enough to fill their pipes "Full Bore." All fixtures other than water-closets shall be provided with strong metallic strainers placed over the outlets. The openings of all such strainers shall be equal to the area of the waste pipe, so that these pipes may be discharged "full bore." Every kitchen and pantry sink shall be constructed on the principle of a flush tank, and shall be provided with a flush pot of not less than 20 gallons capacity, constructed to discharge itself automatically as soon as filled.

Section 29. Drain Pipes, Etc. Drain and connecting ventilating pipes shall be of sufficient size, and made of extra heavy cast-iron pipe if under ground, and if above ground made of extra heavy-cast-iron, wrought-iron of standard weight. Cast-iron drains shall extend not less than ten feet from the inside face of wall, beyond and away from the building.

Drain pipes shall be properly secured by irons to walls, suspended from floor timbers by strong iron hangers, or supported on brick piers. Proper manholes shall be supplied to reach clean-outs and traps. Every drain pipe shall have a proper fall and shall be extended from a point ten feet outside the inside face of the wall, unobstructed, to and through roof, and may also serve as rain water conductor where the combined system is used. The drain pipe shall be supplied with a Y branch with a brass clean-out or iron stopper as directed 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 unless otherwise approved by the commissioner. All drain pipes shall be exposed to sight where practicable within the building, and shall not be exposed to pressure where they pass through the wall.