5.1 General 
                     
                     
                     
                     
                     5.1.1 Other materials and products such as parts made of iron
                        castings, where allowed, products made of copper and copper alloys, rivets, anchors,
                        chain cables, cranes, masts, derrick posts, derricks, accessories and wire ropes are to
                        comply with the applicable requirements of the Rules for Materials of the Society. 
                     
                     
                     
                     
                     5.1.2 The use of plastics or other special materials not covered by
                        these Rules is to be considered by the Society on a case-by-case basis. In such cases,
                        the requirements for the acceptance of the materials concerned are to be agreed by the
                        Society. 
                     
                     
                     
                     
                     5.2 Iron cast parts 
                     
                     
                     
                     
                     5.2.1 As a rule, the use of grey iron, malleable iron or spheroidal
                        graphite iron cast parts with combined ferritic/perlitic structure is allowed only to
                        manufacture low stressed elements of secondary importance. 
                     
                     
                     
                     
                     5.2.2 Ordinary iron cast parts may not be used for windows or
                        sidescuttles; the use of high grade iron cast parts of a suitable type is to be
                        considered by the Society on a case-by-case basis.