Technical Booklet N Drainage·Page 19·3.1
Materials for pipes, fittings and joints
Drains must use materials conforming to specified standards. Different metals must be separated to prevent corrosion, rigid pipes must have flexible joints, and all joints must remain watertight with no obstructions in the pipe line.
The materials for drains should be in accordance with the relevant standards given in Table 3.1. Where different metals are used they should be separated by non-metallic material to prevent electrolytic corrosion. Rigid pipes should have flexible joints. All joints should remain watertight under working conditions. Nothing in the pipes, joints or fittings should project into the pipe line or cause an obstruction.
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