The house trap shall be not less in size than the house drainpipe
it traps, and in no case less than four inches. In old buildings where
the house trap is replaced and it is impossible to conform to these
requirements due to the inability to make an approved connection to
existing lateral piping, a minimum size of four-inch cast-iron house
trap may be used when approved by the Plumbing Inspector. Fresh air
inlets shall be four inches in size for five-inch and six-inch drains,
six inches in size for eight-inch drains, eight inches in size for
ten-inch and twelve-inch drains, 10 inches in size for fifteen-inch
drains and 12 inches in size for eighteen-inch drains. For drains
larger than 18 inches, the area of the air inlet pipes shall be equal
to at least 75% of the area of the trap size. The maximum size of
a fresh air inlet shall be 12 inches nominal diameter. If more than
one fresh air inlet is required, each fresh air inlet shall not exceed
12 inches nominal diameter.
Brass traps of lavatories and sinks shall be made of brass having
a wall thickness not less than No. 17 of the Brown & Sharpe gauge,
and the number of the gauge shall be stamped into the metal for inspection.
Drum traps for bathtubs must have accessible cleanouts. The cleanout plug and cleanout opening of bath traps shall be not less in size than two inches nominal diameter. The body of such traps shall be not less than 2 1/2 inches in diameter, and the trap shall have a water seal of not less than two inches in depth. P traps for bathtubs shall be made of cast brass, cast iron, galvanized durham piping, ABS and PVC. ABS and PVC plastic traps shall conform to the size of the trap and ABS Tubular F409 or PVC Tubular F409 or P Tubular F409 and shall be installed in accordance with §
131-1. The minimum size trap shall be 1 1/2 inches inside nominal diameter and shall have a water seal of not less than two inches and not more than four inches. Cleanouts are not required. Seventeen-gauge traps are not permitted to be used as bath traps. A fourteen-inch-wide and twenty-eight-inch-high trouble door or panel shall be provided to afford access to the bath trap and waste and overflow, and it shall be located on the wall behind the end of the bathtub where the drain outlet is located. The access panel may be 12 inches by 18 inches when located in the ceiling below.
An approved hair or lint interceptor shall be installed wherever
hair or lint, in sufficient quantity to cause line stoppage, may be
introduced into the drainage system, and they shall be installed in
connection with the following uses or occupancies:
A. Commercial, institutional, hotel, club or other laundries equipped
with commercial-type laundry equipment.
B. Beauty parlors and training schools for operators having six or more
lavatories draining to a common house drain.
C. Dry-cleaning establishments.
D. Hide- or fur-processing plants.
E. Establishments having laundry equipment on the premises for public
hire.
Sand and similar interceptors shall be designed and located
so as to be readily accessible for cleaning and shall have a trap
seal of not less than six inches.
A. The wastes from stables, barns, stable yards, barn yards, manure
pits and subsurface drainage pipes shall pass through an intercepting
catch basin before entering the house drain, lateral or public sewer.
B. Floor drains shall be equipped with removable basket strainers wherever
necessary to prevent solids which might cause line stoppage from entering
the drainage lines.