Gives the requirements relating to the sizes and material of tubing for use in hydraulic pressure and return systems. For pressure lines, the requirements apply to the pressure and temperature ranges covered by pressure classes D and E and temperature types II and III as specified in ISO 6771. Tubing materials are included in table 1, outside diameters, wall thicknesses and materials for hydraulic tubing pressure lines are given in table 2. Corresponding national standards for tubing materials are given in table A.1 of annex A.