This Standard specifies the material, design and performance requirements for macro-composite (plastics and metallic materials) solid-top, lightweight access covers, compatible macro-composite or ductile cast iron frames and associated cover/frame assembly inserts, seals and fixings for Class B water industry applications. It applies to single and multiple part covers of square, rectangular and circular shapes.
This design of ventilated covers for specific ventilation and air flow requirements should be undertaken by a suitably qualified hydraulic design engineer.
Purchasing guidelines, based on Appendix B of AS 3996:2006 are provided in Appendix A. It includes information to be supplied at the time of calling for tenders or quotations.
Lightweight composite covers and frames are currently being addressed by the development of EN 124-5 Gully tops and manhole tops for vehicular and pedestrian areas - Part 5: Gully tops and manhole tops made of composite materials. Thermoplastics covers and frames are currently being addressed by the development of EN 124-6 Gully tops and manhole tops for vehicular and pedestrian areas - Part 6: Gully tops and manhole tops made of Polypropylene (PP), Polypropylene with mineral modifiers (PP-MD), Polyethylene (PE) or Polyvinylchloride (PVC-U.
Access cover products conforming to WSA 133 are deemed functionally comparable to those conforming to WSA 132.
This Standard was driven by a desire for lower weight covers to improve worker health and safety outcomes during cover installation and removal. Lightweight macro-composite covers can currently only be economically manufactured for Class B applications and therefore this Standard is restricted to that Class.
Individual Water Agencies are responsible for determining the acceptability of cover products and the applicability of cover assembly specifications, in accordance with Agency asset requirements for particular cover applications. Agencies should assess the various loads imposed on access covers in particular applications, by reference to suitably qualified design engineering professionals, prior to cover selection.