The following types of traps are prohibited:
1. Bell traps.
2. Separate fixture traps with interior partitions, except those lavatory traps made of plastic, stainless steel or other corrosion-resistant material.
3. “S” traps.
4. Drum traps.
5. Trap designs with moving parts.
Each plumbing fixture shall be separately trapped by a water seal trap. The vertical distance from the fixture outlet to the trap weir shall not exceed 24 inches (610 mm) and the horizontal distance shall not exceed 30 inches (762 mm) measured from the center line of the fixture outlet to the centerline of the inlet of the trap. The height of a clothes washer standpipe above a trap shall conform to Section P2706.2. Fixtures shall not be double trapped.
1. Fixtures that have integral traps.
2. A single trap shall be permitted to serve two or three like fixtures limited to kitchen sinks, laundry tubs and lavatories. Such fixtures shall be adjacent to each other and located in the same room with a continuous waste arrangement. The trap shall be installed at the center fixture where three fixtures are installed. Common trapped fixture outlets shall be not more than 30 inches (762 mm) apart.
3. Connection of a laundry tray waste line into a standpipe for the automatic clothes-washer drain shall be permitted in accordance with Section P2706.2.1.
Fixture trap size shall be sufficient to drain the fixture rapidly and not less than the size indicated in Table P3201.7. A trap shall not be larger than the drainage pipe into which the trap discharges.
SIZE OF TRAPS AND TRAP ARMS FOR PLUMBING FIXTURES
|PLUMBING FIXTURE||TRAP SIZE |
|Bathtub (with or without shower head and/or |
|Clothes washer standpipe||2|
|Dishwasher (on separate trap)||11/2|
|Kitchen sink (one or two traps, with or |
without dishwasher and garbage grinder)
|Laundry tub (one or more compartments)||11/2|
|Shower (based on the total flow rate through|
|showerheads and bodysprays)|
|5.7 gpm and less||11/2|
|More than 5.7 gpm up to 12.3 gpm||2|
|More than 12.3 gpm up to 25.8 gpm||3|
|More than 25.8 gpm up to 55.6 gpm||4|
|Water closet||Note a|