This European Standard specifies requirements, test methods, the marking and evaluation of conformity for packaged and/or site assembled domestic wastewater treatment plants (including guest houses and businesses) used for populations up to 50 inhabitants. Small wastewater treatment plants according to this European Standard are used for the treatment of domestic wastewater. It covers plants made of concrete, steel, PVC-U, Polyethylene (PE), Polypropylene (PP), Glass Reinforced Polyester (GRP-UP), Polydicyclopentadiene (PDCPD), PVC and EPDM. The test methods specified in this European Standard establish the performance of the plant, needed to verify its suitability for the end use (see 5.2). This European Standard applies to small wastewater treatment plants for use buried in the ground where no vehicle loads are applied to the product. This European Standard applies to plants where all prefabricated components are factory or site-assembled by one manufacturer and which are tested as a whole. NOTE In some countries, domestic wastewater treatment plants are followed by other systems to conform to national regulations.