This Part of EN ISO 15875 specifies the characteristics of the fitness for purpose of crosslinked polyethylene (PE-X) piping systems, intended to be used for hot and cold water installations within buildings for the conveyance of water whether or not intended for human consumption (domestic systems) and for heating systems, under design pressures and temperatures according to the class of application (see Table 1 of EN ISO 15875-1:2003). This standard covers a range of service conditions (application classes) and design pressure classes. . For values of TD, Tmax and Tmal in excess of those in Table 1of Part 1, this standard does not apply. NOTE It is the re