This part of ISO 12176 specifies an encoding system for data on components, assembly methods and jointing operations for polyethylene (PE) piping systems for gas supply, for use in a traceability system. Reading of the codes can be carried out using alphanumeric or numeric data-recognition systems such as bar-code, magnetic-stripe card or microchip card readers. Other data-recognition systems conforming to ISO/TR 13950 may be used in association with one of the specified recognition systems to obtain the required traceability. This part of ISO 12176 is applicable to PE pipes, fittings and valves conforming to ISO standards for gas supply piping systems and also to the assembly operation utilizing methods such as fusion using a heating tool (butt, socket and saddle fusion), electrofusion (socket and saddle fusion), induction fusion and mechanical jointing.