Two Test Methods Comparison for Power Frequency Electric Field Shielding Materials Evaluation

Abstract

The personal protective equipment (conductive suit) should decrease the power frequency electric field high levels up to occupational permissible limit values for human safety. The personal protective equipment screening property realized by conductive materials which has shielding coefficient. It is relevant for practice to develop test method of conductive suit and materials protection properties by direct power frequency electric field measurement. The paper presents the comparison of results shielding materials testing by different methods. There were compared data of direct power frequency electric field measurement and standard test method according to IEC 60895. The suggested shielding efficiency test method was based on electric field strength measurements inside the metal holder covered by materials test sample placed in high level power frequency electric field. 14 test samples of protective suit textile with use two methods was compared. The results obtained by both methods were analyzed by means of linear approximation function as a correlation between suggested and standard test methods. This function defined minimal shielding efficiency requirements for conductive material of power frequency electric field personal protective equipment measured by suggested method. In prospect, the new method will allow conductive suits manufacturers to predict maximum possible power frequency electric field decrease for compliance with permissible limit values at workplaces. Therefore, the suggested method of shielding efficiency assessment is nearest to standardization in hygienic practice and control at workplaces parameter.