Each fixture, and all outlets for chemical or experimental laboratory tables, or any fixture having a waste-pipe specified, defined herein or not, shall be furnished with a trap, which shall be placed as close as practical to the fixture it serves, or integral therewith and in no case shall trap be more than one foot from said fixture. The waste from one fixture must not connect with the trap of another, except that a residential dishwasher or a two to five part laundry tray may be connected with a single trap. The size of traps for a given fixture shall be as computed in Subsection A.
A. 
Size of fixture traps.
(1) 
Fixture trap size (nominal diameter) shall be sufficient to drain the fixture rapidly and in no case less than given in Table Fixture Traps for Different Type Plumbing Fixtures. No trap shall be larger than the drainage pipe into which it discharges.
Table 860-97A
Fixture Traps for Different Type Plumbing Fixtures
Plumbing Fixture
Minimum Trap Size In Inches
Fixture Unit Value
Automatic Clothes Washer (when connected to drainage system)
2
3
Bathtub (with or without overhead shower)
1 1/2
2
Bedpan washer
3
8
Bidet
1 1/2
2
Combination sink & tray (separate traps for each compartment)
1 1/2
3
Combination sink & tray with food waste grinder (separate traps for each compartment)
1 1/2
4
Dental unit for cuspidor
1 1/2
1
Dental lavatory
1 1/4
1
Drinking fountain
1 1/4
1
Dishwasher — commercial
2 or 3
3 or 5
Dishwasher — domestic
1 1/2
2
Floor drain (above ground)
3
4
Floor drain (below ground)
4
5
Floor drain (car wash or similar functions)
4
6
Kitchen sink — domestic
1 1/2
2
Kitchen sink — domestic, with food waste grinder
1 1/2
3
Kitchen sink — domestic, double bowl (separate traps for each compartment)
1 1/2
3
Kitchen sink — domestic, double bowl with food waste grinder (separate traps for each compartment)
1 1/2
4
Kitchen sink — domestic, double bowl with food waste grinder
(separate traps for each compartment)
1 1/2
4
Lavatory, common
1 1/4
1
Lavatory (barber shop, beauty parlor or surgeons)
1 1/2
2
Lavatory, multiple type (wash fountain or wash sink)
2
2
Laundry tray (1 or 2 compartments)
1 1/2
2
Laundry tray (3 to 5 compartments)
2
3
Shower stall (single)
2
2
Shower stalls (group or gang type, above ground)
3 or 4
2 per head
Shower stalls (group or gang type, below ground)
4
2 per head
Sink — surgeons
1 1/2
3
Sink — flushing rim type, flush valve supplied
3
6
Sink — service type with trap combined
3
4
Sink — service type, ordinary
2
2
Sink — service, janitors style, floor receptor above ground
2, 3 or 4
4
Sink — service, janitors style, floor receptor below ground
4
4
Sink — commercial (pot, scullery, or similar type)
2
4
Sink — commercial (with food grinder unit)
2
4
Urinal — (pedestal, syphon jet)
3
8
Urinal — (wall hung blowout type, flush valve supplied)
2-3
6-8
Urinal — (trough — each two ft. section)
1 1/2
2
Urinal — (wall hung siphon jet)
2
4
Urinal — (wall lip type, flush tank or self closing valve)
1 1/2
2
Urinal — (stall type — existing only)
2
4
Water closet tank operated
3
4
Water closet valve operated
3
8
(2) 
Trap size for plumbing fixtures not listed above will be sized as determined by the Administrative Authority, based on GPM discharge.
B. 
Prohibited traps. The following traps are prohibited:
(1) 
Traps which depend upon moving parts to maintain their seal.
(2) 
Bell traps.
(3) 
Crown vented traps.
(4) 
Separate fixture traps which depend on interior partitions for their seal.
(5) 
"S" traps.
(6) 
Manufactured traps 1 1/4 inches and larger with an area serving as the top and bottom dip not constructed of a one piece 180° bend.
(7) 
Running trap with double cleanouts (except where trap is exposed and accessible).
C. 
Design of traps. Fixture traps shall be self scouring and shall have no interior partitions except where such traps are integral with the fixture. Slip joints or coupling may be used on the trap inlet or within the trap seal.
D. 
Drum traps.
(1) 
Drum traps shall be three or four inches in diameter and shall be provided with a water seal of not less than two inches.
(2) 
The trap screw shall be one size less than the trap diameter.
E. 
Trap seal. Each fixture trap shall have a liquid seal of not less than two inches and not more than four inches, except, where for special conditions, a deep seal may be required by the Administrative Authority.
F. 
Trap cleanouts. Each fixture trap, except those cast integral or in combination with fixtures in which the trap seal is readily accessible or except when a portion of the trap is removable for cleaning purposes, shall have an accessible brass or plastic trap screw of ample size protected by this water seal.
G. 
Trap settings and protection. Traps shall be set level with respect to their water seals and, when necessary, shall be protected from freezing.
H. 
Traps underground. Traps for floor drains shall have a water seal of three inches and shall be provided with removable strainers. Underground traps except "P" traps into which floor drains or similar fixtures with removable strainers discharge, shall be provided with accessible and removable clean outs.
I. 
Provision for evaporation. Where floor drains are subject to evaporation, they shall be provided with a water supply by means of a faucet located not more than three feet above the floor area drain through an approved automatic priming device, or other approved means.
J. 
Building (house) traps.
(1) 
Each house or building drain shall be provided with a horizontal intercepting trap, which shall be the same size as the building drain in which it is installed. The trap shall be provided with an accessible cleanout and a fresh air grill or inlet, which shall terminate in a location acceptable to the Administrative Authority.
(2) 
Relieving vents or fresh air intakes shall be no less than four inches in diameter for building drains up to and including eight inches in diameter. For drains larger than eight inches, the fresh air intake shall be one-half the diameter of the drain. Openings in grill of fresh air inlet shall equal the area of the inlet pipe. The fresh air inlet shall not be used as an area drain.
(3) 
Cleanouts for intercepting traps shall be no less than four inches in diameter for trap sizes up to and including 10 inches. For traps larger than 10 inches the cleanout shall be no less than six inches in diameter.
(4) 
It is recommended that the trap shall be placed inside the cellar or basement wall or as close thereto as practical allowing for construction circumstances. Where house or building traps are placed outside of buildings, it shall be placed as close as practical to the outside of the foundation wall and the fresh air shall be extended above ground, in addition, on traps installed below four feet in depth, a wye and one eighth bend, combination wye or two way cleanout tee shall be installed on the down stream or sewer side of trap with a pipe extending to grade and finished with a cleanout. Also, no trap shall be placed outside of a building if the depth is greater than six feet below finished grade except that in commercial applications, traps may be installed greater than six feet deep provided they are placed in a manhole.
(5) 
Refer to illustration in Chapter 22 for trap assembly dimensions.[1]
[1]
Editor's Note: The trap assembly illustration is on file in the Board of Health office.
K. 
Protection of brittleware traps. Where the use of vitrified clay or brittleware traps installed underground, is approved by the Administrative Authority, the traps shall be embedded in concrete encasement extending four inches beyond the bottom and sides of the trap.
A. 
Location. Cleanouts shall be not more than 50 feet apart in horizontal drainage lines of four inch nominal diameter or less and not more than 100 feet apart for larger pipes.
(1) 
When a sanitary cross is used for side by side or back to back fixtures on waste pipes 1 1/2" and smaller, a cleanout must be provided in the vertical drain above or below the sanitary cross.
B. 
Underground drainage. Cleanouts, when installed on an underground drain, shall be extended vertically to or above the finished grade level or the cleanout may be extended outside the building when found necessary by the Administrative Authority.
C. 
Change of direction. Accessible cleanouts shall be installed at each change of direction of the building drain greater than 45°.
D. 
Concealed piping. Cleanouts on concealed piping shall be extended through and terminate flush with the finished wall or floor; or pits or chases may be left in the wall or floor, provided they are of sufficient size to permit removal of the cleanout plug and proper cleaning of the system.
E. 
Base of soil and waste stacks. A cleanout shall be provided at or near the foot of each vertical waste or soil stack.
F. 
Base of conductors. A cleanout shall be provided at or near the foot of each vertical inside rain conductor. Outside rain conductors shall have cleanout brought to grade level. Except no cleanout will be required where conductor is not controlled by a trap.
G. 
Direction of flow. Every cleanout shall be installed so that the cleanout opens in the direction of the flow of the drainage line or at right angles thereto.
H. 
Cleanout size. Cleanouts shall be of the same nominal size as the drain up to four inches and not less than four inches for pipes up to and including 10 inches in diameter. For pipes or drains 12 inches and larger, the minimum size cleanout shall be six inches.
I. 
Cleanout clearances. Cleanouts shall be so installed that there is a clearance of not less than 18 inches for the purpose of rodding.
J. 
Cleanouts to be kept uncovered. Cleanout plugs shall not be covered with cement, plaster, or any other permanent finishing material. Where it is necessary to conceal a cleanout plug, a covering plate or access door shall be provided which will permit ready access to the plug.
K. 
Cleanout equivalent. A fixture trap or a fixture with integral trap, readily removable without disturbing concealed roughing work, may be accepted as a clean out equivalent, if there is no more than one 90-degree bend or sanitary tee on the line to be rodded.
L. 
Connections to cleanouts prohibited. Cleanout openings shall not be used for the installation of new fixtures or floor drains except where approved in writing by the Administrative Authority and where another cleanout of equal access and capacity is provided.
M. 
Manholes for building sewers. Manholes shall be installed for building sewers 12 inches in diameter and larger where the change of direction is greater than 45° and at distances not greater than 400 feet. For sewers 18 inches to 30 inches, the distance shall not exceed 500 feet. For sewer sizes eight inches to 10 inches, cleanouts shall be installed not more than 100 feet apart, or manholes may be installed in lieu of cleanouts at distances not greater than 400 feet and change of direction greater than 45°.