This International Standard specifies requirements for resistance spot welding in the fabrication of assemblies of uncoated and metallic coated low carbon steel, comprising two or three sheets of metal, where the maximum single sheet thickness of components to be welded is within the range 0,4 mm to 3 mm, for the following materials:— uncoated steels;— hot-dip zinc or iron-zinc alloy (galvannealed) coated steel;— electrolytic zinc, zinc-iron, or zinc-nickel coated steel;— aluminium coated steel;— zinc-aluminium coated steel.This International Standard is applicable to welding of sheets of the same or dissimilar thickness, where the thickness ratio is less than or equal to 3:1. It applies to the welding of three thicknesses, where the total thickness is less than or equal to 9 mm.Welding with the following types of equipment is within the scope of this International Standard:a) pedestal welding equipment;b) gun welders;c) automatic welding equipment where the components are fed by robots or automatic feeding equipment;d) multi welders;e) robotic welders.Information on appropriate welding equipment is given in Annex A, and information on spot welding conditions is given in Annex B. This information is provided for guidance only.Depending on the service conditions of the fabrication, the type of welding equipment, the characteristics of the secondary circuit, the electrode material, and the shape, it is possible that certain modifications are necessary. In such cases, further information can be obtained from the relevant application standard, where one exists.The welding of organic coated or primer coated steels is not within the scope of this International Standard.