| SEWAGE PIPES . | ALIAXIS UK |
| BLÜCHER UK LTD |
| HEPWORTH CLAY & TERRACOTTA |
| HOWARTH TIMBER GROUP |
| HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| MARSHALLS CPM |
| NAYLOR DRAINAGE PRODUCTS LTD |
| OSMA |
| PAM BUILDING |
| POLYPIPE BUILDING PRODUCTS |
| POLYPIPE TERRAIN LTD |
| SEWAGE PIPES Backflow Valves | ACO TECHNOLOGIES PLC - BUILDING DRAINAGE |
| ALUMASC WATER MANAGEMENT SOLUTIONS |
| DALLMER LTD |
| FERNCO LTD |
| MARLEY PLUMBING & DRAINAGE |
| WAVIN |
| SEWAGE PIPES BS 4660:2000 | HUNTER PLASTICS LTD |
| OSMA |
| POLYPIPE TERRAIN LTD |
| SEWAGE PIPES BS 5481 | OSMA |
| POLYPIPE BUILDING PRODUCTS |
| SEWAGE PIPES BS 5911-1:2002 Kitemarked | MARSHALLS CPM |
| SEWAGE PIPES BS EN 13476 | MARLEY PLUMBING & DRAINAGE |
| OSMA |
| SEWAGE PIPES BS EN 13598 Parts 1 and 2 | OSMA |
| SEWAGE PIPES BS EN 1401:1998 Part 1 | NAYLOR DRAINAGE PRODUCTS LTD |
| OSMA |
| POLYPIPE TERRAIN LTD |
| SEWAGE PIPES BS EN 1401:1998 Part 1 Kitemarked | OSMA |
| SEWAGE PIPES BS EN 1916:2002 | MARSHALLS CPM |
| SEWAGE PIPES BS EN 295-1:2013 | HEPWORTH CLAY & TERRACOTTA |
| NAYLOR DRAINAGE PRODUCTS LTD |
| SEWAGE PIPES HDPE | MARLEY PLUMBING & DRAINAGE |
| SEWAGE PIPES Ovoid Flexible Jointed | MARSHALLS CPM |
| SEWAGE PIPES Precast Concrete | MARSHALLS CPM |
| SEWAGE PIPES Precast Concrete BS 5911 | MARSHALLS CPM |
| NAYLOR DRAINAGE PRODUCTS LTD |
| SEWAGE PIPES PVC-u | ALIAXIS UK |
| HOWARTH TIMBER GROUP |
| HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| SEWAGE PIPES PVC-u AGREMENT CERTIFICATE HOLDERS | MARLEY PLUMBING & DRAINAGE |
| OSMA |
| SEWAGE PIPES PVC-u BS 5481 | OSMA |
| POLYPIPE BUILDING PRODUCTS |
| SEWAGE PIPES PVC-u Structured Twinwall Pipes | HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| SEWAGE PIPES PVC-u WIS 4-35-01 CERTIFICATE | HUNTER PLASTICS LTD |
| MARLEY PLUMBING & DRAINAGE |
| OSMA |
| SEWAGE PIPES Stainless Steel | BLÜCHER UK LTD |
| SEWAGE PIPES Vitrified Clay BS EN 295-1: 2013 Kitemarked CE Marked | HEPWORTH CLAY & TERRACOTTA |
| NAYLOR DRAINAGE PRODUCTS LTD |
