RS ISO 21138-2: 2020 PLASTICS PIPING SYSTEMS FOR NON-PRESSURE
UNDERGROUND DRAINAGE AND SEWERAGE —
STRUCTURED-WALL PIPING SYSTEMS OF
UNPLASTICIZED POLY(VINYL CHLORIDE) (PVC-U),
POLYPROPYLENE (PP) AND POLYETHYLENE (PE) —
PART 2: PIPES AND FITTINGS WITH SMOOTH EXTERNAL
SUR