Plastics piping systems for non-pressure underground drainage & sewerage. Unplasticized poly (vinyl chloride) (PVC-U), polypropylene (PP) & polyethylene (PE). Guidance for assessment of conformity Pipework systems, Pipes, Thermoplastic polymers, Unsaturated polyesters, Thermosetting polymers, Polymers, Plastics, Reinforced materials, Water supply & waste systems (buildings), Surface-water drainage, Drainage, Sewerage, Conformity, Approval testing, Pipe fittings