AS/NZS 4798(INT):2005

Specifies requirements for the design and manufacture of non-person man entry polyethylene maintenance shafts intended for buried sewerage systems at depths up to 6 m and diameters up to DN 300 comprising a moulded chamber and riser in one-piece seamless construction or a moulded base jointed to an extruded pipe shaft manufactured from a compatible material.

This Interim Standard specifies design and manufacture requirements for a polyethylene maintenance shaft (MS) comprising a moulded chamber and riser in one-piece seamless construction, or a moulded chamber jointed to a riser (normally a pipe) manufactured from a compatible material. MSs are intended for installation in sewerage systems (up to DN300) for transportation of sewage at atmospheric pressure and average service temperatures up to 25°C. They are intended for buried vertical installation at depths up to 6m, without buckling collapse and without exceeding long-term diametral distortion and stress limits as specified. Long-term design criteria limits are 50 year extrapolated or predicted values. Provided installation and operating conditions conform to the guidelines in this Standard, life expectancy may exceed 50years.The test requirements specified in this Standard may be achieved by alternative test methods if such methods can be shown to provide equal or greater accuracy than those specified herein. In all cases of dispute, the methods specified in this Standard shall be considered the reference test methods.Methods for demonstrating compliance with this Interim Standard are given in AppendixA.

First published as AS/NZS 4798(Int):2005.