This part of BS7291 specifies general requirements and methods of test for thermoplastics pipe and fitting systems intended for use within buildings for the conveyance of cold water, including drinking water, and heated water for use in domestic hot and cold water distribution and heating installations. These systems are also suitable for the conveyance of cold water for a period of 50 years at a temperature of 20°C and a design pressure of 12½ bar.
This British Standard is applicable only to Class “S?? pipes and fittings.
Details of the specific applications and service conditions are given in Table1.
This specification is applicable to rigid or flexible plain pipes, pipes incorporating a polymeric barrier to inhibit gas permeability through the pipe wall and multilayer pipes having a nominal outside diameter up to and including 110mm.
NOTE1 Methods of test are given in AnnexA, AnnexB, AnnexC and AnnexD. AnnexE gives guidance on factory control procedures.
NOTE2 BS7291‑2 and BS7291‑3 specify additional requirements for pipes and/or fittings manufactured from specific thermoplastics materials. They should be read in conjunction with this part of BS7291.
NOTE3 Reference to “pressure?? in this part of BS7291 means “gauge pressure??, unless otherwise stated.
NOTE4 Where the pipe or fitting is of a thermoplastics material covered by BS7291‑1, BS7291‑2 or BS7291‑3, either the requirements for preventing or controlling the extent of permeation specified in the applicable part, e.g. by use of a barrier pipe, should be followed, or a corrosion inhibitor added to the primary circuits in accordance with BS5955‑8.