Important Numbers 3

76 mm Ø

Minimum outlet size of a sand interceptor.

0.2 m²

Minimum net opening dimension of the inlet section of a sand interceptor.

610 mm

Minimum depth of sand interceptor under the invert of the outlet pipe.

0.09 m²

Increase in the area of inlet section for each 18.9 LPM or fraction thereof over 75.7 LPM.

50% of the inlet section

Minimum area of sand interceptor outlet section.

762 mm

Distance of trap to vent for 32 mm Ø.

1067 mm

Distance of trap to vent for 38 mm Ø.

1524 mm

Distance of trap to vent for 51 mm Ø.

1829 mm

Distance of trap to vent for 76 mm Ø.

3048 mm

Distance of trap to vent for 102 mm Ø and larger.

1829 mm

Maximum developed length between water closet and vent.

GA 26

Minimum thickness of galvanized sheet metal for rainwater downspout or conductor.

0.6 meter

Rainwater piping commencing ____ from the exterior of a building may be suitable approved materials.

102 mm

Extension of roof drain strainers above the surface of the roof.

1.5x the area of outlet

Minimum total net inlet area of roof drain with dome-type strainers.

2x the area of outlet

Minimum total net inlet area of drain with roof deck strainers.

102 mm/hour

Rainfall intensity normally used around Manila area.

50%

Additional for area of 1 wall.

35%

Additional for area of 2 adjacent walls.

0%

Additional for area of 2 opposite walls

50%

Additional for side of tall building exposed to rain

0.392x diameter

When gutter has semi-circular bottom, depth of equivalent area of rectangular gutter

0.8862x diameter

When gutter has semi-circular bottom, width of equivalent area of rectangular gutter

7/24 full

Basis of Table 11-4

3:1

Ratio of the side dimension of a rectangular vertical piping

More than 61 m

Public sewer is not available if

6"

Minimum diameter of building sewer, but not less than the size of the building drain

2%

Recommended slope for building sewer

1%

Allowable slope for drainage piping 102 mm or 152.4 mm in diameter given site constraints

0.5%

Allowable slope for drainage piping 203 mm or larger in diameter

0.60 m

Distance of building sewer from outer face of any building foundation or wall

0.30 m

Minimum depth of building sewer below finished ground surface

Exceeding 135°

Aggregate offset angle to be provided with an additional cleanout

Less than 3 m

Length of building sewer not requiring a cleanout

91 m

Maximum distance between manholes

0.30 m

Distance between bottom of water pipe and top of sewer or drain line

0.30 m

Horizontal distance between water line and sewer or drain line

0.30 m

Distance between sewer/drainage piping and water pipes crossing above

3 m

Minimum distance of water pipe joints away from a sewer line

1.5 m

Distance within property line where abandoned building sewer shall be plugged or capped

30 days

Maximum time from connection to public sewer to fill abandoned disposal facility

0.60 m

Minimum horizontal distance of a building/structure from the building sewer

0

Minimum horizontal distance of property line from building sewer

15.2 m

Minimum horizontal distance of water supply wells from building sewer

15.2 m

Minimum horizontal distance of streams from building sewer

0.30 m

Minimum horizontal distance of on-site domestic water service line from building sewer

0.30 m

Minimum horizontal distance of public water main from building sewer

7.6 m

Allowable reduced distance from water supply wells if approved materials are used

No minimum

Maximum/Minimum FU on 152 mm building sewer @ 2%

3

900/275, Maximum/Minimum FU on 203 mm building sewer @ 2%

6

800/300, Maximum/Minimum FU on 254 mm building sewer @ 2%

11

200/235, Maximum/Minimum FU on 305 mm building sewer @ 2%

25.4 mm

Minimum depth to be filled with molten pig lead

3.2 mm

Extension of the finished joint below the rim of the hub

Schedule 80

Minimum wall thickness of threaded plastic pipe

19 mm

Minimum thickness of exposed wiped surface on each side of a wiped joint and at least as thick as the material being joined

0.002 (0.2%)

Maximum lead content allowable for solders and fluxes in potable water piping

Schedule 80

Job-fabricated female screws

76 mm to 102 mm

Enlargement of closet bend from ___ shall be considered an obstruction

6.4 mm

Minimum width of continuous and indelibly colored stripe marking for hard drawn copper tubing

Type K

Green copper tubing

Type L

Blue copper tubing

Type M

Red copper tubing

Type DWV

Yellow copper tubing

19.56 kg/sq. m ; 1.6 mm thick

Minimum weight and thickness of sheet lead for lead safe pans

14.63 kg/sq. m ; 1.2 mm thick

Minimum weight and thickness of sheet lead for flashing or vent terminals

3.2 mm

Minimum wall thickness of lead bends and lead traps

178 mm Ø

Approximate diameter of closet rings or flanges

38 mm

Width of closet ring or flange

6.4 mm

Minimum thickness of caulked-on closet rings or flanges

51 mm

Minimum overall depth of caulked-on closet rings or flanges

4

Number of bolts per water closet

2%

Slope of threaded-type drainage fittings

102 mm or larger

Sizes of valves that shall have cast iron bodies

Less than 102 mm

Sizes of valves that shall have cast brass or bronze bodies

Up to 51 mm

Sizes of valves that shall be brass and bronze metal

1 psi

2.31 feet of head

1 psi

6.895 kPa

103.42 kPa or 15 psi

Minimum pressure for a group containing flushometer valves

55.16 kPa or 8 psi

Minimum pressure for a group containing flush tanks

9.79

Multiplier to the elevation above the water main to determine loss in static pressure

75%

Multiplier to the total demand for fixtures with combined hot and cold water to arrive in maximum separate demands

3 m/sec

Maximum velocity of water for sizing supply piping

14 m²

Minimum area of trench bottom for disposal field

1 ft to 3 ft

Sidewall area below the leach line may be added to the trench bottom absorption area

50%

Where leaching beds are permitted in lieu of trenches the area of each bed shall be at least ___ greater than the tubular requirements for trenches

1.5 m

Separation distance of leach bed excavation from the water table

3 m

Separation distance of seepage pit excavation from the water table

2

Minimum number of compartments of a septic tank (as per plumbing code)

3

Minimum number of compartments of a septic tank (as per new ordinance)

2/3 of tank capacity

Minimum capacity of inlet compartment

2 m³

Minimum liquid capacity of inlet compartment

1.5 m

Minimum length of inlet compartment

0.9 m

Minimum width of septic tank

1/3 of tank capacity

Maximum capacity of secondary compartment

1 m³

Minimum capacity of secondary compartment

1.5 m

Minimum length of secondary compartment if tank has over 6 m³ capacity

2

Minimum number of manholes for septic tank

508 mm

Minimum dimension of a manhole