This International Standard specifies the definitions and requirements for buried manholes and inspection chambers (circular or non-circular) installed to a maximum depth of 6 m from ground level to the invert of the main chamber and manufactured from unplasticized poly(vinyl chloride) (PVC-U), polypropylene (PP), polypropylene with mineral modifiers (PP-MD) or polyethylene (PE). These products are intended for use in traffic areas and underground installations conforming to the general requirements given in EN 476 and are used outside the building structure (application area code “U”). They are therefore marked accordingly with a “U”. This International Standard is only applicable to those chamber/manhole items where the manufacturer has clearly stated in the documentation how the components shall be assembled to create a complete manhole or inspection chamber. The inspection chambers covered by this International Standard comprise the following: — inspection chambers providing access to the drainage or sewerage system by means of inspection and cleaning equipment; — chambers designated as manholes providing man access to the drainage or sewerage system. The inspection chamber or manhole can be manufactured by various methods, e.g. injection moulding, rotational moulding, low-pressure moulding or fabricated from components made in accordance with other International Standards. The jointing of components can be achieved using: — elastomeric ring seal joints; — adhesive joints for PVC-U; — welded joints for PVC-U, PP and PE; — extrusion welding; — mechanical jointing. NOTE Both manholes and inspection chambers can be site-assembled from different components, but can also be manufactured as a single unit. In either case, the following functional parts can be recognized: a) base (always present); In the case of a one-piece chamber or manhole, the base part ends at a distance of 300 mm measured from the top of the main channel. b) riser (depth-dependent); c) telescopic part (design-dependent); d) cone (dependent on the design of near-surface components and their recommended installation); e) other near-surface components.