This International Standard specifies the general properties of the polyethylene (PE) compounds for the manufacture of pipes, the physical and mechanical properties of the pipes made from these compounds, and the requirements for the marking of such pipes, intended to be used for the supply of gaseous fuels. It deals with three types of pipe: - 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) as specified in Annex C, where all layers have the same MRS rating; - PE pipes (outside diameter dn) with a peelable, contiguous thermoplastics additional layer on the outside of the pipe (“coated pipe”) as specified in Annex D. This International Standard also gives guidance on a calculation and design scheme on which the maximum operating pressure (MOP) of the pipes is based. The pipes are intended to be buried.