This European Standard specifies characteristics and related requirements, assessment methods, the marking and assessment and verification of constancy of performance (AVCP) procedures for prefabricated septic tanks used for populations up to 50 inhabitants. Prefabricated septic tanks in accordance with this European Standard are: - used for the treatment of domestic wastewater including that of guest houses and businesses; - made of concrete, steel, PVC-U, Polyethylene (PE), Polypropylene (PP), Glass Reinforced Polyester (GRP-UP) and/or Polydicyclopentadiene (PDCPD); - used buried in the ground; - with or without extension shaft; - made of prefabricated components that are factory-assembled by one manufacturer and which are tested as a whole. This European Standard does not cover prefabricated septic tanks: - where vehicle loads apply to it; - receiving grey water only; - assembled in situ from prefabricated kits.