This European Standard specifies units made from polyester resin concrete (PRC, see 3.1.18), and their joints, for the construction of inspection chambers with inverts not exceeding 2 m deep and for manholes, intended to be used within a drain or sewer system operating without pressure. It applies to products for use outside buildings in buried installations to be installed by open-trench techniques.This document applies to nominal sizes from DN 600 to DN 3000 for chamber rings and shaft rings having a circular shape.The intended use of these products is to provide access to buried drain or sewer systems for the conveyance of wastewater, i.e. sewage, rainwa