Assessment of the occupational exposure to the magnetic field produced by spot welding guns in controlled environment and actual working conditions

In this paper the evaluation of the exposure to the magnetic field produced by several resistance spot welding guns is presented. Alternating current and medium frequency direct current technologies are taken into account. The measurements of the magnetic field is performed first in controlled environment. The results make it possible to define a safety area where the safety limits are not exceeded. According to the current regulatory framework also the dosimetric assessment is performed. This analyses show that the exposure limit values are not exceeded even for the working conditions in which the operator is outside the previously defined safety area. Finally, measurements of the magnetic field levels in actual working conditions are carried out. It is shown that the magnetic flux density does not exceed the limits even when more than one guns are operated close to one another. The results provide an up-to-date view of the problem with reference to the rules and methodologies imposed by the latest European Directive related to the occupation exposure to electromagnetic fields.