The compositions ands mechanical properties are only suggested to ensure good weld ability and good formability in conjunction with control of ensure that the materials selected are compatible with the design the indicated properties are intended to assure that the ROPS or FOPS will have meaningful resistance to brittle fracture. The impact toughness requirement is the conventional Charpy V Notch evaluation: it is primarily a quality control check and the indicted temperature does not directly relate to operating conditions. Three steel product categories are covered: hollow structural members@ plates@ bars and shapes@ and castings.