Traps
shall be placed as near the fixture as possible and in no case shall
a trap be more than 2' (developed length) from the waste outlet of
the fixture. All traps shall have at least a 1-1/2" and not more than
a 4" seal. Traps placed below the floor shall have a brass trap screw
for cleaning which shall be accessible. The interior walls of cast
brass traps, unless machined, shall have been sand blasted so that
there are no sharp points or obstructions in the trap. All traps shall
be rigidly supported and set true with respect to their water level
and shall be located to protect the trap seal. Traps which depend
upon the action of movable parts to form a seal shall not be used.
Traps which depend upon concealed interior partitions to form a seal
or which have interior partitions, which in case of defect will permit
the passage of sewer air shall not be used.
Each
bathtub shall be provided with an extra heavy lead drum trap, 4" x
8" or larger except when the “durham” system is used,
drum traps may be of cast iron or brass. Traps on bathtubs shall be
placed in such a manner that the cleanout shall be accessible. The
outlet from a drum trap shall be wiped into the trap in such a position
that the waste outlet shall be water sealed to a depth not less than
2-1/2" and not more than 4" and not more than 6" laterally from the
trap. The inlet shall enter below that water level in the drum trap.
Drum traps serving bathtubs shall not connect to the lead bend or
lead ferrules under any water closets. When drum traps are installed
on a continuous waste and vent system, the waste line may be connected
using a 4" x 2" Y on a horizontal between lead bend and stack, or
a 2" side outlet fitting similar to “Wisconsin sanitary tee”
commonly known as “crowfoot fittings,” or by using separate
fittings such as 4" x 2" sanitary tee. When this construction is used,
the drum traps shall be ventilated through the waste fitting and the
outlet of such fitting shall not be set below the dip of the trap.
Inlet and outlet of drum trap shall not be less than 1-1/2" in diameter.
A distance not to exceed 3-1/2' developed length will be permitted
between trap and point of entrance to waste line, and the distance
from the top of the solder nipple to the drum trap on inlet side of
trap shall not exceed 2' of developed length. This construction may
be used only where there are no fixtures on floor above wasting into
the main soil or waste stack.
Traps
for lavatories shall be cast brass traps with seal not less than 1-1/2"
or more than 3" in depth and with a discharge capacity equal to that
of a 1-1/4" pipe, so constructed as to provide access in case of stoppage.
The
connection between drainage pipes and water closets, floor outlet
service sinks, pedestal urinals, and earthenware trap standard fixtures,
shall be made by means of brass or hard lead floor flanges soldered
or lead welded to the lead bend or at least six inches of lead pipe.
C.I. stubs or bends with C.I. calk-on type closet flanges may be used
in concrete slab floors constructed on the ground. The connection
shall be bolted to the fixture by means of red brass bolts with an
approved gasket, washer, setting compound or white lead putty between
the fixture and the connection. No commercial putty shall be used.
The floor flange shall be set on an approved firm base. The lead connection
shall be independent connection for fixture only. All other waste
pipes shall discharge into a separate fitting. In wooden joist construction
the distance between the wiped joint on the lead stub serving the
fixture shall not be less than 4" from the underside of the floor.
Traps
for kitchen sinks shall be extra heavy lead or cast brass traps with
seal not less than 1-1/2" or more than 3" in depth and with a discharge
capacity equal to that of a 1-1/2" pipe.
Traps
for urinals shall be cast iron or cast brass traps with seal not less
than 1-1/2" or more than 3" in depth and with a discharge capacity
equal to that of a 1-1/2" pipe. Urinals with integral traps will be
permitted.
Traps
for lavatories, sinks, urinals, or other fixtures which connect with
screw pipe, as provided for herein, shall be cast brass and of the
New York or Los Angeles pattern.
Traps
for wash trays shall be drum traps of no smaller dimensions than 4"
x 8" extra heavy lead and one trap may be used for a battery of three
trays and the trap outlet shall not be less than 2" in diameter. Traps
for single wash trays may be extra heavy lead or cast brass P traps
with seal not less than 1-1/2" or more than 3" in depth and with a
discharge capacity equal to that of a 1-1/2" pipe. Wash trays with
a partition forming two compartments with one waste outlet will be
considered as a single wash tray.
Each
shower bath shall be provided with trap of cast iron, brass or lead
with water seal of not less than 2" or more than 4". Inlet and outlet
of this trap shall not be less than 2" in diameter. Showers installed
independent of shower heads over bathtubs shall be wasted through
a double drainage floor drain appliance as made by the various manufacturers,
and approved by the plumbing inspector. Drilling of the brass strainer
will not be permitted. Waste shall connect with either vertical stack
or horizontal house drain independent of all other fixtures, and in
no case shall be connected to lead bend or lead ferrule serving water
closets. When 2" P traps are used under showers in order to keep from
cutting the floor joist, the extension from trap to strainer shall
be of cast iron or brass and the distance from floor line to trap
shall not exceed 2', and the distance from water seal to point of
entrance on vertical or horizontal connection or continuous waste
shall not exceed 5'. Beyond this limit, traps shall be revented.
Wherever
built-up shower baths are installed except those constructed on concrete
slabs directly on the earth, the base of the shower stalls shall be
lined with sheet lead and weighing not less than four pounds to the
square foot. Lead shower pans shall be protected on both upper and
lower sides by coating with asphalt and application of 30 pounds asphalt
felt over such coating on both sides of pan. The sheet lead shall
be turned up on all sides to a height of not less than 6". Base and
walls of shower stall shall be of nonabsorbent materials and impervious
to moisture.
When
shower baths are installed in manufacturing establishments, shop and
engine or boiler rooms in basements or if the floors in such places
are constructed on the ground using concrete or tile, then the double
drainage fixture and lead pan need not be used. Cast iron combination
P trap with strainer may be used with wastes and vents in such business
establishments.
Prefabricated
shower stalls with metal walls and enameled metal, stainless steel
or terrazzo receptor may be installed on the ground floor of residential
buildings only. Said stalls installed in residential buildings above
the ground floor shall have terrazzo receptors. Shower walls and receptor
shall be connected with watertight joints in such installations.
Bar
sink wastes shall not be smaller than 2" in diameter and the discharge
shall be intercepted by a cast iron grease trap having dimensions
not less than 19" x 11-1/2" x 10" deep or equal capacity, when bar
connections do not exceed three openings including those from floor
drain and iceboxes. Soda fountain wastes and a combination of from
4 to 12 bar sinks or waste openings including floor drains shall have
a waste not smaller than 3" in diameter, and the grease trap shall
not be less than 20" in diameter by 20" deep or equal capacity, and
2" P traps shall be installed directly under the bar sink opening.
The bar sink openings shall be permanently connected to the P traps.
When a combination of waste openings from a soda fountain exceed 12
and does not exceed 36, the drain shall be 4" in diameter and shall
discharge into a grease trap 30" in diameter by 30" deep or equal
capacity.
A
floor constructed of concrete, terrazzo or other impervious material
shall be installed from front line of the counter to the rear line
of the back bar for entire length of walkway. A floor drain not less
than 2" in diameter shall be installed for every 100 square feet of
this area but the distance between floor drains shall not exceed 15'.
Horizontal pipes installed under bars and fountains shall be located
at least 5" above the floor. All iceboxes or refrigerator drains shall
waste on indirect connection to floor drains or open fixtures.
When
a grease trap is located below finish floor grade, a cast iron frame
and cover shall be placed in the finished floor directly over grease
trap so it will be accessible for cleaning. Grease traps shall be
revented although they are not classed as fixtures. Each fixture and
appliance connected to a grease trap shall be trapped and each fixture
and appliance so trapped shall be listed as a separate fixture, and
subject to inspection and permit fees as such. A vent shall be installed
at the farthest point from the grease trap on waste line and this
vent shall be equal in size to the waste line. Where the bar or fountain
is 30' from the grease trap an additional vent not less than 1/2 the
diameter of the waste line shall be installed in front of the first
waste opening. These vents shall not be laid horizontally more than
6' from the waste line to the vertical rise. A cleanout shall be installed
at base of said vertical vents in an accessible location.
The
vents may be extended through the roof separately or they may be connected
together provided the connection is located 1' above water level of
the fixture or they may be connected to any sanitary vent of sufficient
size. A cleanout shall be installed flush with the floor at the end
of each waste line and this cleanout shall be equal in size to that
of the waste line. The waste line between the grease trap and the
vents shall be of uniform size. A blow-off or catch basin will not
be accepted in lieu of a grease trap.
(1965 Code, sec. 15-163)
Each dental unit or dental cuspidor shall be connected to a
drum trap having not less than 1-1/2" waste outlet connected to waste
as herein required.
Waste
pipes from kitchen sinks in any hotel, restaurant, boardinghouse,
school and all other public places serving food or where drinks are
prepared for sale and are served on the premises shall discharge into
a grease interceptor (trap) made of cast iron with a removable cover.
One sink, or from one compartment to four compartment sinks, shall
waste through a grease interceptor (trap) of not smaller size than
19" x 11-1/2" x 10" deep or equal capacity.
Sinks
shall be constructed of corrosion-resistant metal, not lighter than
18 gauge, and fabricated so that joints are smooth and easily cleanable.
Sinks for hand dish washing operations shall be built with at least
three compartments and the minimum size for each compartment shall
be 14" x 14" x 12" deep (or equal capacity so that no side shall be
less than 12"). This minimum size three compartment sink will not
be suitable for a place washing large quantities of dishes. A smaller
compartment for use as a waste sink may be constructed with this three
compartment sink. When it is desired to separate the glass and dish
washing procedure another compartment may be added.
All
the fixtures and floor drains in hotels, kitchens, restaurants, cafeterias,
drive-ins, hospitals, schools and other public places where food is
prepared or cooked may waste into one grease interceptor that is vented
as heretofore specified and each fixture wasting into this grease
interceptor shall be trapped and vented as specified in this article.
To determine the proper size of the waste lines to this grease interceptor
the fixture unit valve as specified in fixture unit table of this
division shall be used. The total number of fixture units wasting
into the grease interceptor shall determine the proper size waste
line and the inlet and outlet of the grease interceptor shall not
be smaller than the line wasting into it.
For
calculating the required sizes of grease interceptors the rate of
discharge from each fixture connected to the interceptor shall be
based upon the rates shown in the fixture unit table as set forth
in this division. The grease retaining capacity of each grease interceptor,
in pounds of grease, shall be equal to twice the rate of flow capacity
in gallons per minute of wastewater so that the interceptor shall
remove and retain 90% of the grease discharged into it up to its required
capacity of accumulated grease.
Unless
otherwise approved by the chief plumbing inspector, grease interceptors
shall separate grease while it is in the liquid state; that is, separation
shall be accomplished by differential gravity methods, assuming temperatures
of waste at 150 degrees F. and a rate of rise of grease at 1.05' per
second reduced to 0.025' per second to allow for turbulence. The chief
plumbing inspector shall establish detailed formulas for further determining
the effectiveness of grease interceptors submitted for approval under
these regulations and shall prepare and maintain a list of interceptors
which are approved.
All
grease interceptors shall be maintained by the owner at his expense,
in continuously efficient operation at all times. Such grease interceptors
shall be located on the premises served.