Content Page: 9 Drainage and Sewerage

  • Traps In Soil-Water Fittings

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    Except as is provided for urinals in section 13, every soil-water fitting shall be provided with an approved trap, built integrally with the fitting, but such trap may, with the approval of the local authority, be joined to the fitting if the junction is above the water-line of the trap and the joint is firm…

  • Traps In Waste-Water Fittings

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    (1) Except as permitted in subsection (4), there shall be provided immediately beneath every waste-water fitting an approved trap having a removable cleaning-plug or other approved means of cleaning situated below the water-seal. (2) The nominal bore of such a trap shall be not less than— a) the size of the waste-water fitting outlet to…

  • Single-Stack Systems

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    (1) Single-stack systems may be used under the following conditions— a) all soil and waste branch pipes shall be separately connected to the vertical soil stack; b) the minimum depth of water-seals shall be 75 millimetres for waste-water fittings, and 50 millimetres for soil-water fittings; c) The waste-pipe used in conjunction with a 32-millimetre-diametre trap…

  • Protection Of Waste-Water Traps

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    (1) In the one-pipe system, the water-seal of the trap of every waste-water fitting shall be protected by means of an anti-siphon pipe; Provided that, where horizontal waste-pipes are back-vented as described in section 46,the anti-siphon pipes may be omitted. (2) In the two-pipe system, the water-seal of the trap of every waste-water fitting shall…

  • Ventilation Of Soil-Water Fittings

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    Where several soil-water fittings are connected to a branch soil-pipe which is provided with a vent connected to such branch soil-pipe immediately short of the farthest soil-water fitting on such branch, and such vent is connected to another vent at a point not less than 150 millimetres above the highest water-level possible in any such…

  • Minimum Drop To Fittings

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    Where a waste-pipe, soil-pipe or private sewer serves two or more sanitary fittings, there shall be a drop of at least 150 millimetres from every such fitting, measured from the invert of the trap outlet to the invert of such waste-pipe, soil-pipe or private sewer.

  • Impervious Floors

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    (1) Every soil-water fitting and every bath shall be placed on an impervious floor. (2) Every shower-fitting shall be placed over a bath or over an impervious flor graded to a waste-water outlet connected through a trap fitted with a grating to the sewer.

  • Electrolytic Action

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    There shall be no connexion between metal pipes and cisterns or tanks of dissimilar metal where, in the opinion of the local authority, such association of dissimilar metals might set up electrolytic action.

  • Support Of Piping And Fittings

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    (1) Strap hangers may be used for all pipes of nominal bore up to 50 millimetres, but ring hangers shall be used for all pipes of greater size. (2) All pipes, except those laid in the ground, shall be securely fixed at frequent intervals to that portion of the wall or other rigid portion of…

  • Size, Fall, Line And Changes In Direction

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    (1) All sewers shall be of a size capable of tanking the discharge into them, calculated in accordance with the relevant provisions of this chapter, with a minimum internal diameter of 100 millimetres. (2) Sewers of 100-millimetre and 150-millimetre diameter shall be laid with gradients lying between a maximum of 1 in 10 and a…