1. Requir ements of
Sanitar y Pipe
wor ks
PREPARED BY:
ZARINA BT MAT SAPRI
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2. REQUIREMENTS OF
SANITARY PIPE WORKS
1) Water seals in traps
Such provision shall be made in the drainage
system of a building, either above or below the
ground as may be necessary to prevent the
destruction under working conditions of the water
seal in any trap in the system, or in any appliance
which discharge into the pipe work system
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3. 2) Sizes Of Pipes
• The internal diameter of any soil, waste and
vent pipe shall not be less than the outlet of
any appliances which discharge into traps or
outlet of traps.
• Based on Building Regulation 1985, the
internal diameter of soil pipe shall not be less
than 100 mm and internal diameter for waste
pipe shall not be less than 32 mm.
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4. 3) Material, Fixing And JointS
•Any soil pipe, waste pipe or vent pipe
shall be composed of suitable materials
of adequate strength and durability.
•Bends in pipe should have the largest
practicable radius of curvature and there
should be no change in the cross-section
of pipe throughout the bend.
•Pipe should be supported throughout
their length, without restricting thermal
movement.
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5. A soil and waste pipe should be
fixed inside of the building,
except a waste pipe from
ground floor, where the pipes
discharge to the floor gully trap.
See Figure 3.12. All pipes
should be placed where they
are reasonably accessible for
maintenance, repair and have
access for internal cleansing.
Joint should be made so that
they remain air-tight and any
material used for jointing should
not cause electrolytic corrosion.
Figure 3.12: Waste pipe from
appliance situated on ground floor
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6. 4) Traps
A trap should be fitted closed to waste or soil appliance,
unless the appliance has integral trap. They can be fixed to
serve individually (see Figure 3.13) or for a group of
appliances ( see Figure 3.14). All the traps should have an
adequate diameter water seal and means of access for
internal cleansing.(see Table 3.1)
Table 3.1: Minimum internal diameter of trap
Domestic type of Diameter Domestic type of fitting Diameter
fitting (mm) (mm)
Wash basin 32 Drinking fountain 19
Bidet 32 Hotel & canteen sink 40
Sink / Bath / 40 Urinal bowl 40
Shower
Wash – tub 50 Urinal stall( 1 to 2 ) 50
Kitchen waste 40 Urinal stall ( 3 to 4 ) 65
disposal
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7. Figure 3.13: Washbasin with individual trap
Figure 3.14: Trap with a group of washbasin
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8. 5) Tests
A soil and waste system
should be capable of
withstanding a smoke
test or air test for a
minimum period of 3
minutes, at a pressure
equivalent to a head of
water not less than 38
mm head of water ( see
Figure 3.15 ). The
Building Regulation 1985
requires that during the 3
minutes every trap
should maintain a water
seal of at least 25 mm. Figure 3.15: Air Test on soil and waste
pipe
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