A.
Load on drainage piping. The load on drainage system piping shall be computed in terms of drainage fixture units in accordance with Table 860-132A and § 860-132A.
|
Table 860-132A
Fixture Unit Values for Various Plumbing
Fixtures and Minimum Trap Size
| |||
|---|---|---|---|
|
Plumbing Fixtures
|
Fixture Unit Value
|
Minimum Trap Size In Inches
| |
|
Automatic clothes washer (when connected to
drainage system)
|
3
|
2
| |
|
Bathtub (with or without overhead shower)
|
2
|
1 1/2
| |
|
Bedpan washer
|
8
|
3
| |
|
Bidet
|
2
|
1 1/2
| |
|
Combination sink & tray (separate traps
for each compartment)
|
3
|
1 1/2
| |
|
Combination sink & tray with food waste
grinder (separate traps for each compartment)
|
4
|
1 1/2
| |
|
Dental unit for cuspidor
|
1
|
1 1/2
| |
|
Dental lavatory
|
1
|
1 1/4
| |
|
Drinking fountain
|
1
|
1 1/4
| |
|
Dishwasher — commercial
|
3 or 5
|
2 or 3
| |
|
Dishwasher — domestic
|
2
|
1 1/2
| |
|
Floor drain (above ground)
|
4
|
3
| |
|
Floor drain (below ground)
|
5
|
4
| |
|
Floor drain (car wash or similar functions)
|
6
|
4
| |
|
Kitchen sink — domestic
|
2
|
1 1/2
| |
|
Kitchen sink — domestic, with food waste
grinder
|
3
|
1 1/2
| |
|
Kitchen sink — domestic, double bowl (separate
traps for each compartment)
|
3
|
1 1/2
| |
|
Kitchen sink — domestic — double
bowl with food waste grinder (separate traps for each compartment)
|
4
|
1 1/2
| |
|
Lavatory, common
|
1
|
1 1/4
| |
|
Lavatory (barber shop, beauty parlor or surgeons)
|
2
|
1 1/2
| |
|
Lavatory, multiple type (wash fountain or wash
sink)
|
2
|
2
| |
|
Laundry tray (1 or 2 compartment)
|
2
|
1 1/2
| |
|
Laundry tray (3 to 5 compartments)
|
3
|
2
| |
|
Shower stall (single)
|
2
|
2
| |
|
Shower stalls (group or gang type, above ground)
|
2 per head
|
3
| |
|
Shower stalls (group or gang type, below ground)
|
2 per head
|
4
| |
|
Sink — surgeons
|
3
|
1 1/2
| |
|
Sink — flushing rim type, flush valve
supplied
|
6
|
3
| |
|
Sink — service type with trap combined
|
4
|
3
| |
|
Sink — service type, ordinary
|
2
|
2
| |
|
Sink — service type, janitors style, floor
receptor (above ground)
|
4
|
2, 3 or 4
| |
|
Sink — service type, janitors style, floor
receptor (below ground)
|
4
|
4
| |
|
Sink — commercial (pot, scullery, or similar
type)
|
4
|
2
| |
|
Sink — commercial (with food grinder unit)
|
4
|
2
| |
|
Urinal (pedestal, syphon jet)
|
8
|
3
| |
|
Urinal (wall hung blowout type, flush valve
supplied)
|
6-8
|
2-3
| |
|
Urinal — trough (each 2 ft. section)
|
2
|
1 1/2
| |
|
Urinal (wall hung siphon jet)
|
4
|
2
| |
|
Urinal (wall lip type, flush tank or self-closing
valve)
|
2
|
1 1/2
| |
|
Urinal (stall type — existing only)
|
4
|
2
| |
|
Water closet tank operated
|
4
|
3
| |
|
Water closet valve operated
|
8
|
3
| |
|
Type of Fixture
|
Fixture Unit Value
| ||
|
Unlisted fixture drain or trap size
| |||
|
1 1/4 inch or less
|
1
| ||
|
1 1/2 inch or less
|
2
| ||
|
2 inches or less
|
3
| ||
|
2 1/2 inches or less
|
4
| ||
|
3 inches or less
|
5
| ||
|
4 inches or less
|
6
| ||
B.
Values for continuous flow. Fixture unit values for
continuous or semicontinuous flow into a drainage system, such as
from a pump, sump ejector, air conditioning equipment or similar device
shall be computed on the basis of two fixture units for each gallon
per minute of flow.
Pipe sizes shall be determined from Table 860-133A
and Table 860-133B on the basis of drainage load computed from Table
1101.1 and Section 1101.2.
|
Table 860-133A
Maximum Loads on Building Drains and Sewers
| |||||
|---|---|---|---|---|---|
|
Diameter of Drain
(inches)
|
Maximum Number of Fixture Units that may
be connected to any portion1 of the building drain or the building sewer
| ||||
|
Fall per Foot
| |||||
|
1/16"
|
1/8"
|
1/4"
|
1/2"
| ||
|
*1 1/4"+
|
N.P.
|
N.P.
|
1
|
1
| |
|
*1 1/2"+
|
N.P.
|
N.P.
|
3
|
4
| |
|
*2"+
|
N.P.
|
N.P.
|
21
|
26
| |
|
*2 1/2"+
|
N.P.
|
N.P.
|
24
|
31
| |
|
*3"
|
N.P.
|
N.P.
|
27 (2)
|
36 (2)
| |
|
4"
|
N.P.
|
180
|
216
|
250
| |
|
5"
|
N.P.
|
390
|
480
|
575
| |
|
6"
|
N.P.
|
700
|
840
|
1,000
| |
|
8"
|
1,400
|
1,600
|
1,920
|
2,300
| |
|
10"
|
2,500
|
2,900
|
3,500
|
4,200
| |
|
12"
|
3,900
|
4,600
|
5,600
|
6,700
| |
|
15"
|
7,000
|
8,300
|
10,000
|
12,000
| |
|
NOTES:
| |
|---|---|
|
1
|
Includes branches of building drain.
|
|
*
|
When building drain is above basement floor.
|
|
+
|
No water closets permitted.
|
|
(2)
|
Not over two water closets.
|
|
N.P.
|
Not Permitted.
|
|
Table 860-133B
Maximum Loads on Soil and Waste Stacks
and Branches of Stacks
| ||||
|---|---|---|---|---|
|
Diameter of Drain
(inches)
|
Any Horizontal (1) Fixture Branch
|
One Stack of 3 stories in Height —
Includes 1 & 2 Story Bldgs.
|
More than 3 stories in height
| |
|
Total for stack
|
Total at one Story or Branch Interval
| |||
|
1 1/4" Waste
|
1
|
2
|
2
|
1
|
|
1 1/2" Waste
|
3
|
4
|
8
|
2
|
|
2" Waste
|
6
|
10
|
24
|
6
|
|
2 1/2" Waste
|
12
|
20
|
42
|
9
|
|
3" Soil and/or Waste
|
20 (2)
|
30 (3)
|
60 (3)
|
16 (2)
|
|
4" Waste
|
160
|
240
|
500
|
90
|
|
5" Waste
|
360
|
540
|
1,100
|
200
|
|
6" Waste
|
640
|
960
|
1,900
|
350
|
|
8" Waste
|
1,400
|
2,200
|
3,600
|
600
|
|
10" Waste
|
2,500
|
3,800
|
5,600
|
1,000
|
|
12" Waste
|
3,900
|
6,000
|
8,400
|
1,500
|
|
NOTES:
| |
|---|---|
|
(1)
|
Does not include branches of the building drain.
|
|
(2)
|
Not over two water closets.
|
|
(3)
|
Not over six water closets.
|
A.
All soil and waste stacks shall extend in a vertical line from the highest to the lowest horizontal branch or fixture connected thereto through the roof and shall not be reduced in size, except that where offsets in vertical stacks are unavoidable such increase in sizing as outlined in § 860-138B of this chapter shall not be considered as a reduction in stacks. Also first floor water closets, the location of which, prevents a connection to available soil stacks, may connect to the building drain and be relieved by a proper size relief vent.
B.
This procedure shall not be considered as a reduction
in the soil stack, however, all soil stacks extending beyond the first
floor level provided to receive the discharge of water closets or
similar fixtures shall not be reduced in size. No soil or waste stack
shall be smaller in size than the attending vent stack, nor shall
any soil or waste stack be smaller in size than the largest horizontal
branch connected thereto, except that a four by three water closet
connection shall not be considered as a reduction in pipe size.
Any building or structure containing at least
one water closet or pedestal urinal shall have a building drain installed
with at least one stack vent or vent stack carried full size through
the roof not less than three inches in diameter. No soil, waste or
vent pipe shall be installed on the outside of a new building. Any
building or structure having a sewer connection with a public or private
sewer which has a drainage system installed to receive discharge from
floor drainage only, will require a minimum of two inch relief vent
which must be extended through the roof of the building from the rear
of the main building drain and be of a larger size where warranted.
Building drains installed for roof drainage only will not require
a relief vent.
When provision is made for the future installation
of fixtures, those provided for shall be considered in determining
the required sizes of drain and vent pipes. Where future connections
are left in the roughing of soil and waste stacks, vent connections
must also be provided, and all such future connections shall be terminated
with a plugged fitting or fittings so arranged as to form no dead
end.
Sanitary drainage systems installed underground
or below a basement or cellar floor shall be four inches in diameter,
except;
A.
Traps used for bath tubs and individual showers may
be 1 1/2 or two inches respectively.
C.
In residential installations, waste and/or soil pipe
three inch, two inch, and 1 1/2 inch may be installed within
the perimeter of a toilet room, and three inch and two inch installed
as branches of the building drain provided the developed length does
not exceed 10 feet from the main building drain. (NOTE: Use of cast
iron two inches and smaller shall be prohibited.)
A.
Offsets of 45° or less.
(1)
An offset in a vertical stack, with a change of direction
of 45° or less from the vertical, may be sized as a straight vertical
stack.
(2)
On buildings with four or more stories above an offset,
no horizontal branch shall connect to the stack within two feet above
or below the offset, or may connect with the travel portion of the
offset at least two feet from either change in direction.
B.
Offsets of more than 45°. A stack with an offset
of more than 45° from the vertical shall be sized as follows:
(1)
The portion of the stack above the offset shall be
sized as for a regular stack based on the total number of fixture
units above the offset, except that the portion of the stack above
the offset shall not be smaller in size than required for straight
vertical stacks based upon total fixture unit count for the entire
stack.
(2)
The offset shall be sized as for a building drain
Table 860-133A, "Maximum Loads on Building Drains and Sewers".
(3)
The portion of the stack below the offset shall be sized as for the offset or based on the total number of fixture units on the entire stack, whichever is the larger. A relief vent for the offset shall be installed in accordance with Article XIII, § 860-147E, and in no building with four or more stories above an offset, shall the horizontal branch of fixtures on a floor directly above an offset connect to the stack at that level, but shall connect with the horizontal portion of the offset at least two feet from either change in direction, or it shall connect at least two feet below the offset. (See illustration.[1])
[1]
Editor's Note: The illustration is on file
in the Health Department office.
C.
Above highest branch. An offset above the highest
horizontal branch is an offset in the stack-vent and shall be considered
only as it affects the developed length of the vent. But no such offset
shall be made in the stack-vent at an angle greater than 45° unless
suitable provisions are made to prevent the accumulation of rust,
scale or condensate.
D.
Below lowest branch. In the case of an offset in a
soil or waste stack below the lowest horizontal branch, there shall
be no change in diameter required if the offset is made at an angle
of not greater than 45°. If such an offset is made at an angle
greater than 45° to the vertical, the required diameter of the
offset and the stack below it shall be determined as for a building
drain Table 860-133A. No relief vent will be required for an offset
in a stack when such offset is located at least ten feet below the
lowest horizontal branch connected to the stack, however, the attending
vent stack may be started or located at this position. (See attached
illustration for this location.[2])
[2]
Editor's Note: The illustration is on file
in the Health Department office.
A.
Slope of horizontal drainage piping. Horizontal drainage
piping shall be installed in uniform alignment at uniform slopes not
less than 1/4 inch per foot for three inch diameter and less, and
not less than 1/8 inch per foot for diameters of four inches or more.
Where conditions do not permit building drains and sewers to be laid
with slope as great as that specified, a lesser slope may be permitted
as determined from Table 860-133. A provided computed velocity is
at least two feet per second.
B.
Depth of horizontal building drains. Horizontal building
drains inside building (at highest point) a minimum 12" from finished
floor to flow line of pipe shall be required on all underground sanitary
building drains, where sufficient fall is available.
Fittings used to change direction. Change in
direction in drainage piping shall be made by the appropriate use
of 45-degree wyes, long or short sweep bends, sixth, eighth, or sixteenth
bends, or by a combination of these or equivalent fittings. Single
sanitary tees may be used in drainage lines only where the direction
of flow is from the horizontal to the vertical. Quarter bends may
be used in drainage lines where the direction of flow is from the
horizontal to the vertical, or vertical to the horizontal.
A.
Prohibited fittings. No fitting or connection which
has an enlargement chamber or recess with a ledge or shoulder, or
reduction in pipe area shall be used. No running threads, bends, or
saddles shall be used. No drainage, or vent piping shall be drilled
or tapped unless otherwise permitted by the Administrative Authority.
B.
Heel or side-inlet bends. A heel or side-inlet quarter
bend may be used provided, the heel or side inlet is a sufficient
distance above the flow line of the fitting as determined by the Administrative
Authority.
C.
Obstruction to flow. No fitting, connection, device,
or method of installation which obstructs or retards the flow of water,
waste, sewage, or air in the drainage or venting system in an amount
greater than the normal frictional resistance to flow, shall be used
unless it is indicated as acceptable in this code, or is approved
by the Administrative Authority as having a desirable and acceptable
function and as of ultimate benefit to the proper and continuing functioning
of the plumbing system, the enlargement of a three-inch closet bend
or stub to four inches shall not be considered an obstruction, provided
the horizontal flow line of insert is continuous without forming a
ledge.
In the installation or removal of any part of
a drainage system, dead ends shall be avoided except where necessary
to extend a cleanout so as to be accessible.
A.
All building drains shall be discharged into the sewer by gravity flow. When differences exist in the elevation of the sewer and the main building drain prohibiting the flow by gravity, a variance may be granted pursuant to § 860-6 by the Director, but shall require, in addition to any other requirements, that the alternate system meet all requirements of this chapter. Any alternate system shall discharge into a tightly covered and vented sump from which the liquid shall be lifted and discharged into the building gravity drainage system by automatic pumping equipment or by any equally efficient method approved by the Administrative Authority.
B.
Any building having a single lower level, with fixtures
or drains discharging sewage or liquid waste below the normal grade
of the gravity system may use a sump as an auxiliary method to discharge
from the single below grade level only. The use of an auxiliary sump
will not require a variance but must be approved by the Administrative
Authority.
C.
Design of sumps. Sump and pumping equipment shall be so designed as to discharge contents accumulated in the sump during the cycle of emptying operation and the storage of drainage in a sump or ejector shall not exceed 12 hours. Sumps in other than one or two-family residences receiving the discharge of six or more water closets shall be provided with duplex pumping-equipment. The sump vent shall be of proper size to meet the venting requirements as outlined in Article XIII, § 860-159, "Venting of Sumps and Sewers". Sumps receiving the discharge of clear water, such as rain water, subsoil or seepage drainage, (excluding drainage from sanitary fixtures), will not require a vent. A back water valve and a gate valve shall be installed in the discharge line of every sump or receiving tank.
D.
Construction of sanitary sumps. Every sump or receiving
tank, receiving the discharge of plumbing fixtures or sanitary drains,
shall be constructed of approved material and the lid or cover shall
be gas and air tight.
