This part of ISO 11299, in conjunction with ISO 11299-1, specifies requirements and test methods for close-fit lining systems intended to be used for the renovation of gas supply networks. It applies to pipes and fittings, as manufactured, as well as to the installed lining system. It is applicable to polyethylene (PE) pipes for both independent and interactive pressure pipe liners as well as associated fittings and joints for the construction of the lining system. It is applicable to PE pipes, fittings and assemblies intended to be used at an operating temperature of 20 °C as the reference temperature. NOTE For other operating temperatures, guidance is given in ISO 4437-5:2014.