This document presents a code of practice dealing with polyethylene (PE) pipes and fittings for buried pipeline systems outside buildings, conforming to the ISO 4437 series, and designed to transport gaseous fuels [as defined in ISO 4437-1, e.g. methane, liquified petroleum gas (LPG), manufactured gas and hydrogen] within the temperature range –20 °C to +40 °C. This document also gives appropriate temperature-related requirements.
The code of practice covers mains and service lines whose components are prepared for fusion or mechanical jointing. It also gives instructions for the design, storage, handling, transportation, laying conditions and fusion quality control of PE pipes and fittings as well as subsequent joint testing, backfilling, pipe system testing and commissioning.
NOTE For the renovation code of practice, reference is made to the ISO 11299 series and to ISO 11295 for classification and to the ISO 21225 series for further information for trenchless replacement.
The minimal requirements for the jointing methods are given in:
— Annex A (butt fusion);
— Annex B (electrofusion); and
— Annex C (mechanical jointing).
In some countries the use of heated-tools socket and saddle fusion is permitted; information on heated-tools fusion jointing techniques is given in Annex D.
In the case of ground movement or shaking (e.g. earthquakes, etc.) it can be necessary to implement precautions mentioned in this document following guidelines provided by authorities (e.g. Eurocode 8, EN 12007-1:2012, Annex A, etc.),
Workers' health and safety issues are outside the scope of this document.