ISO 4437-2:2014 specifies the characteristics of pipes made from polyethylene (PE) for piping systems in the field of the supply of gaseous fuels. It also specifies the test parameters for the test methods referred to in this International Standard. In conjunction with part of ISO 4437-1, ISO 4437-3, ISO 4437-4, and ISO 4437-5, it is applicable to PE pipes, fittings and valves, their joints, and joints with components of PE and other materials intended to be used under the following conditions: the maximum operating pressure (MOP) is based on the design stress determined from the compound minimum required strength (MRS) divided by the C factor, and taking into account rapid crack propagation (RCP) requirements; and a temperature of 20 °C is taken as reference temperature for the design basis. ISO 4437-2:2014 covers three types of pipes: PE pipes (outside diameter dn) including any identification stripes; PE pipes with co-extruded layers on either or both the outside and/or inside of the pipe (total outside diameter dn), where all PE layers have the same MRS rating; and PE pipes (outside diameter dn) with a peelable and contiguous thermoplastics additional layer on the outside (coated pipe).