Plastics piping systems for pressure and non-pressure water supply, drainage or sewerage. Glass-reinforced thermosetting plastics (GRP) systems based on unsaturated polyester (UP) resin|Dimensional tolerances, Pipework systems, Sewerage, Test methods, Sewers, Reinforced materials, Pipes, Mechanical properties of materials, Pipe fittings, Plastics, Plastic pipelines, Pipe couplings, Unsaturated polyesters, Glass fibres, Water supply and waste systems (buildings), Thermosetting polymers, Dimensions, Drainage, Pressure, Size, Performance, Polyesters