Developing a tool for implementing the "Electromagnetic Fields" European Directive for operators of radiating machinery

Outline of reasons and objectives
Industrial applications based on the physical properties of electromagnetic waves can expose operators to high levels. In 2011, INRS published the results of a study based on measurements at 600 work stations. They showed that seven families of machines could expose employees to field values greater than the action values set by European Directive 2004/40/EC. That directive was replaced in June 2013 by Directive 2013/35/EU. It sets new threshold values that are sometimes less stringent and makes it mandatory for companies to assess exposure. A new study has thus been conducted to supplement the preceding findings and to develop a tool designed to enable companies to make simplified assessments of this risk.
Approach
This study was conducted in collaboration with the 9 Physical Measurement Centres of the CARSATs/CRAMs (French Occupational Health and Pension Insurance Funds/French Regional Health Insurance Funds). The measurement protocols, drafted for the 7 families of machines studied in the previous study, were kept so as to continue to collect and analyse the data homogeneously and in a manner representative of the exposure conditions. One thousand datasheets, each corresponding to a work station, were filled in. For each station, an exposure index equal to the ratio between the measured value and the Action Value (AV) defined by Directive 2013/35/EU was calculated. MRI and NMR equipment were not taken into account in this second study because the levels measured were low in the control booths where the operators work.
Main results
In spite of the less stringent thresholds for the new directive, the measurements taken gave exposure indices greater than 1 for 4 of the 7 families of equipment, sometimes on only some of the stations and sometimes on the majority of them. A value greater than 1 means that the AV is exceeded and the company must then improve the situation. For most of the equipment, the only prevention approach consisted in moving the work station as far as possible away from the emission source, even though other technical solutions existed. A parametric study made it possible to classify the machines into homogeneous sub-families based on the emitted field levels. This work made it possible to construct a simplified assessment tool making it possible, on the basis of the characteristics of the machinery, of the tasks performed, and of the position of the operator, to predict the probability of conformity or non-conformity of the exposure relative to the new directive.
Discussion
To the best of our knowledge, this study and the previous one were the first in France to have conducted an assessment of industrial exposure to electromagnetic radiation. These studies have enabled a good practice guide to be written to help companies identify the main risk equipment, assess the probabilities of exceeding the AV, and implement prevention means. The simplified assessment tool will be accessible from the “electromagnetic fields” file on the INRS website.