Description

This Standard specifies design and manufacture requirements for a PVC-U maintenance shaft (MS) comprising a fabricated or injection-moulded, or both, chamber jointed to an extruded PVC riser.

Scope

MSs are intended for installation in sewerage systems (up to DN 300) 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 6 m, without buckling or collapse and without exceeding specified long-term diametral distortion and stress limits.

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 50 years.