A. 
The discharge from all plumbing fixtures and other sanitary drains on the premises shall be drained through properly installed piping to the public sewage system or as prescribed in § 131-105B(3) or 131-112.
B. 
No piping connected to the plumbing system shall be installed in any transformer vault, except that a floor drain may discharge to an independent seepage pit and to a location approved by the Plumbing Inspector or the floor drain may discharge to an indirect waste pipe which shall be located on the exterior of the transformer vault; the indirect drainage piping shall be in accordance with Article XII.
C. 
In special cases, such as baptismal founts, wastewater may be discharged directly to the earth with the approval of the Plumbing Inspector.
D. 
Every building or other structure or premises in or on which liquid or waterborne wastes accumulate shall be equipped with an approved drainage system to convey all liquid or waterborne wastes to a public sewer, provided that, where a public sewer is not available, other approved provisions shall be made for disposing of such wastes in conformity with applicable laws, ordinances, rules and regulations. Where a public sewer is not available, residences may connect to an approved private sewer through a house trap.
E. 
The drainage system for each building or other structure shall be entirely separate and independent of every building drainage system serving any other building or structure, except that:
(1) 
Buildings, other than residences, and other structures on the same premises and under the same ownership may be connected to the same house drain.
(2) 
Where one building stands in the rear of another building on an interior lot and a separate house drain cannot be provided for the rear building through an alley, yard or other open public space, the house drain of the front building may be connected to serve the rear building, provided that the house drain of the front building is of adequate size and in suitable condition to serve both front and rear buildings and provided that such dual use is approved by the Plumbing Inspector.
(3) 
The minimum size of the main house drain receiving the discharge of water closets shall be four inches inside nominal diameter.
F. 
Existing house drains shall not be used to serve new buildings until they have been examined by and tested under the direction of the Plumbing Inspector, and approved for such use.
G. 
Except in one-family dwellings, the drainage from all plumbing fixtures located at the basement or cellar level shall be connected to the horizontal piping of the house drain or to a horizontal branch pipe properly vented. This shall apply to the lowest level of a building built on a slab on grade. Such fixtures may be connected to a vertical soil or waste stack, provided that no fixtures are connected to the vertical soil or waste stack above the basement or cellar level.
A. 
Soil and waste piping above the ground within buildings. Soil and waste piping for drainage systems within a building other than underground drains shall be cast iron, either hub or hubless, galvanized wrought iron, galvanized steel, galvanized yoloy, galvanized malleable iron split couplings (victaulic), brass, DWV or heavier copper tubing, lead, stainless steel (409 Type G copper coated), ABS or PVC plastic. All materials shall conform to § 131-13. Where necessary for corrosive, industrial or laboratory wastes, the drains shall be lead, acid-resisting cast-iron, chemical stoneware, chemical porcelain, modified epoxy resin, saran-lined steel pipe, stainless steel teflon-lined couplings, Zytel mechanical couplings or heat-resistant prestressed, borosilicate glass, polyethylene and polypropylene. Where copper tubing is used for urinal drains, the tubing shall be Type K copper. Neither ABS nor PVC piping shall be installed intermittently in the drainage system.
B. 
Underground piping within the building. All sanitary drains, when underground within building and to a point 10 feet beyond the building wall, shall be of hub-type cast-iron pipe PVC Schedule 40. Where necessary for corrosive industrial wastes, lead, acid-resisting cast iron with mechanical joints and polypropylene may be used. Bury pac glass pipe may be used on branch waste lines only. Short branch soil or waste connections may be of lead pipe.
C. 
House drains.
(1) 
For house drains from a point 10 feet beyond the building wall in a trench separate from water service or water distributing pipe, the drainpipe shall be of cast iron, hard-temper copper tube of a weight not less than Type L vitrified clay pipe, concrete, plastic, asbestos cement, the underground water service or water distributing pipe and the house drain shall be not less than 10 feet apart horizontally and shall be separated by undisturbed or compacted earth, or in accordance with § 131-70 with permission from the Plumbing Inspector.
(2) 
For house drains from a point 10 feet beyond the building wall in trench with water service or water distributing pipe, when underground water service or water distributing piping is installed in the same trench with the house drain, the drainpipe shall be of cast iron or hard-temper copper tube of a weight not less than Type L. The water pipe shall be laid on a bench or on a solidly tamped backfill at a level at least 12 inches above the top of the drainage pipe and at least 12 inches horizontally from the center of the drainage pipe.
(3) 
When a house drain is installed in filled or unstable ground, it shall be of cast iron or hard-temper copper tube of a weight not less than Type L.
D. 
Approval drainage type fittings shall be used on all drainage piping. Pipe and fittings shall conform to the applicable specifications in § 131-13.
A. 
Fall for small piping. Horizontal drainage piping of three inches in diameter and less shall be installed with a fall of not less than 1/4 inch per foot.
B. 
Fall for large piping. Horizontal drainage piping more than three inches and up to and including six inches in diameter shall be installed with a fall not less than 1/8 per foot, and horizontal drainage piping larger than six inches in diameter shall be installed with a fall of not less than 1/16 inch per foot. Where conditions do not permit house drains or sewers to be laid with a fall as great as that specified, a lesser slope may be approved by the Plumbing Inspector, provided that the computed velocity flow is not less than two feet per second.
C. 
The minimum size of the main house drain receiving the discharge of water closets shall be four inches inside nominal diameter.
D. 
Minimum cover. Traps on underground drainage piping installed outdoors or where subject to frost action shall have a minimum cover of three feet. Underground drainage piping installed parallel to a foundation wall shall be at least three feet from the building foundation wall when the depth does not exceed four feet and one foot additional distance from the foundation wall shall be required for each additional one foot depth below four feet.
E. 
Changes in direction in drainage piping shall be made by the appropriate use of forty-five-degree wyes, long or short-sweep bends, one-sixth, one-eighth or one-sixteenth bends, or by combinations of these or equivalent fittings. Single and double sanitary tees shall be used in drainage lines only where the flow is from the horizontal to the vertical. Tees and crosses may be used in the vent and water distributing systems.
F. 
No double-hub fitting or single or double-tee branch shall be used as a drainage fitting. No bands or saddles and no quarter bends shall be used in the drainage system. Repair plates may be used in old work in the drainage and vent system. No drain, drainage or vent piping shall be drilled or tapped on new work. Drilling or tapping with use of a repair plate may be done on old work only on stacks with no fixtures above, with permission from the Plumbing Inspector. A quarter bend may be used on sanitary drainage piping but only when installed as a replacement fitting for an ideal bend having no side outlets for receiving small fixture drains. Any fitting or connection that offers abnormal obstruction to flow through a drain is prohibited.
A. 
Fixture unit values. The relative load weights of fixtures shall be determined in accordance with the following table, in which the following definitions shall apply:
(1) 
Private installations. For the purpose of this section, "private installations" shall mean those installations which are not generally available to members of the public.
(2) 
Public installations. For the purpose of this section "public installation" shall mean those installations available to the public in public buildings.
Fixture Unit Load Values
Fixtures
Private Installations
Public Installations
Bathroom group, consisting of 1 lavatory, 1 water closet, 1 bathtub or shower stall with or without shower head over bathtub
8
Bathtub with 1 1/2-inch trap, with or without shower head over bathtub
2
4
Bathtub with 2-inch trap, with or without shower head over bathtub
3
6
Cup sink
2
Dishwashers, domestic, automatic
4
Drinking fountain
1/2
Floor drain
6
Kitchen sink with 1 1/2-inch trap with or without garbage grinder unit, in sink, with 1 1/2-inch or 2-inch trap
4
4
Kitchen sink with 2-inch trap with or without garbage grinder unit, in sink, with 1 1/2-inch or 2-inch trap
5
Laundry tray with 1 1/2-inch trap (1 or 2 compartment)
4
4
Laundry tray with 2-inch trap
5
Lavatory with 1 1/4-inch or 1 1/2-inch trap
1
2
Lavatory (barber, beauty parlor or surgeon's)
3
Service sink (slop sink), mop receptor
3
Service sink, flushing rim with flush valve
10
Shower stall with 2-inch trap
2
4
Shower stall with required 3-inch trap
8
Urinal, stall and washout
5
Urinal, pedestal, siphon-jet and blowout
10
Urinal trough, for each 5 feet
2
Wash fountain, duo
2
Wash fountain, any other size
5
Washing machine, domestic, automatic
4
Water closet
6
12
Fountain cuspidor (dental chair)
1
Sink, soda fountain or bar
2
B. 
Values for unlisted fixtures. Fixture unit values for fixtures not listed and not determined by similarity to a fixture listed therein shall be determined from the following table:
Other Fixture Unit Load Values
Fixture Unit Value
Required Fixture Drain or Trap Size
(inches)
Private Installations
Public Installations
1 1/4
1
2
1 1/2
2
4
2
3
6
3
5
10
4
6
12
C. 
Values for continuous flow. For a continuous or semicontinuous flow in a sanitary drainage system, such as from a bilge pump, ejector, air-conditioning equipment, commercial laundry, dishwashing equipment or similar device, each gallon per minute of flow shall be deemed to be two fixture units.
D. 
Maximum fixture unit load. The maximum number of fixture units that may be connected to a given size of house drain, horizontal branch or vertical soil or waste stack shall be in accordance with Table P-1 below.
(1) 
The size of a soil or waste stack is determined by both the fixture units on the stack plus the fixture units on the horizontal branch from the base of the soil or waste stack connected to the house drain.
(2) 
The size of the horizontal branch from the base of the soil or waste stack connected to the house drain is determined by the fixture units and gradient fall.
(3) 
The size of the house drain is then sized according to its gradient fall and total number of fixture units.
(4) 
If the building is 50 feet and not more than 120 feet in height above the grade level, at curb the vertical soil or waste stacks connected to the house drain or any of its branches shall be one size larger than that given in Table P-1. If the building is more than 120 feet in height, the vertical soil or waste stacks connected to the house drain or any of its branches shall be two sizes larger than that given in Table P-1. When the soil or waste stacks are connected to a horizontal branch pipe which discharges into a soil or waste stack, the size of the vertical soil or waste stacks connected to the horizontal branch pipe, when 50 feet and not more than 120 feet in height, shall be one size larger than that given in Table P-1. When more than 120 feet in height, the vertical soil or waste stacks connected to the horizontal branch pipe shall be two sizes larger than that given in Table P-1. The developed length of the soil or waste stacks shall be determined by measuring the distance between the center line of the horizontal branch pipe to the roof. If a relief vent is installed on all horizontal branches, below the top floor, between the soil or waste stacks and the first fixture on the horizontal branch, the soil or waste stack sizes shall be as given in Table P-1, regardless of the height of the building.
Table P-1
Table of Minimum Pipe Sizes According to Fixture Unit Load
(Maximum fixture units that may be connected)
House Drain or Horizontal Branch
(inches of fall)
Pipe Size
(inches)
1/16
1/8
1/4
1/2
Vertical Soil or Waste Stack
1 1/4
2
2
1 1/2
4
6
6
2
10
18
20
2 1/2
27
36
36
31
48
65
75
4
50
100
200
225
5
130
225
420
480
6
330
480
875
1,015
8
500
850
1,100
2,000
2,320
10
1,050
1,650
2,320
3,800
4,500
12
1,800
3,000
4,500
6,500
8,100
15
3,600
6,000
8,100
10,000
13,600
NOTES:
1
Limit of two water closets.
E. 
Minimum size of soil and waste pipe. No soil or waste stack shall be smaller than the largest branch draining into it. Soil stacks receiving the discharge of water closets shall not be less than three inches in diameter, as provided in Subsection D, Table P-1. Three-inch soil stacks shall be limited to two water closets. No horizontal soil pipe or waste pipe draining pedestal urinals or water closets shall be less than three inches in diameter. When using three-inch ideal bends (closet bends) to receive the discharge of water closets, this fitting shall be a blind bend containing no drainage connections for other fixtures. No waste pipe shall be less than 1 1/4 inches in diameter, except that waste pipe drip lines from soda fountains, coffee urns and refrigerator cases may be one inch nominal diameter, not over 12 feet in length. Fixture branch pipes shall conform to § 131-29. The minimum size of the main house drain receiving the discharge of water closets shall be four inches inside nominal diameter.
F. 
Future fixtures. When provision is made for the future installation of fixtures, drainage pipes shall be of size which will accommodate future fixtures, and construction to provide for such fixture installation shall be terminated with a plugged fitting at the stack so as not to form a dead end and shall be vented as prescribed in Article XI.
A. 
Ejectors and receiving tanks. All building drains carrying sewage or other sanitary waste which cannot discharge to the house drain by gravity shall discharge into a tight receiving tank, so located as to receive the wastes by gravity. The wastes shall be lifted and discharged into the house drain by duplex pumps, ejectors or an equally efficient method approved for the sewage handled. Such receiving tanks shall be discharged automatically.
B. 
The drainage piping discharging into the tight tank receiving sewage or other sanitary waste shall be vented as provided in Article XI.
C. 
When sewage is lifted into the house drain by air pressure, the air delivered from the compressed air tank shall be not less than the cubic-foot capacity of the receiving tank, and the minimum pressure of the air delivered shall be one pound for each foot of height the sewage is to be lifted. The receiving tank shall be tested for 50 pounds per square inch.
D. 
Pumps, ejectors, air compressors and air tanks shall be located so as to be readily accessible.
E. 
The discharge of the pump or ejector shall be directly into the house drain through a suitable wye fitting in front of the vent and shall be equipped with a suitable check valve and gate valve; the discharge pipe must be vented when over 12 feet from a vented line as provided in Article XI. A fresh air inlet shall be installed as prescribed in § 131-98A and B.
131h 85E.tif
F. 
Small fixture wastes which cannot discharge to the house drain by gravity may, with the permission of the Plumbing Inspector, be pumped to the house drain in front of the vent without the use of a sump or receiving tank. The discharge line shall be equipped with a check valve and gate valve installed on the pipe discharging into a wye fitting on the house drain.
A. 
Steam exhaust from pressing machines, steam boiler blowoffs or steam condensate drips shall not discharge directly to the atmosphere nor be connected directly to the house drainage system. Cooling methods shall be provided which automatically cool the exhaust to 140° F. or less, if the waste is discharged to the house drainage system. If potable water is used with a direct connection to the cooling apparatus, a safe waste connection shall be used.
B. 
If a condensate or blowoff tank is used, the tank shall be sized to a capacity of 1/3 of the total water capacity of the vessel or vessels discharging into the tank.
(1) 
The tank shall be vented through the roof with galvanized wrought iron, galvanized alloy or copper vent pipe not less than two inches in size.
(2) 
The overflow shall discharge into the house drain in accordance with Subsection A.
(3) 
The overflow pipe shall be submerged inside the tank.
A. 
An approved relief or surge tank shall be installed in connection with all equipment, such as hydraulic elevators or lifts, operated by water pressure. Such relief or surge tanks shall be arranged and connected so that the pressure of discharge therefrom into the building drainage system shall at no time exceed five pounds per square inch.
B. 
The discharge connection from such relief or surge tank shall be connected and arranged so as to provide a trapped water seal not less than 12 inches in depth within the relief or surge tank, and where there is danger of backflow or back pressure, effective measures shall be taken to prevent backflow in accordance with the requirements of these regulations.