Abstract: Safety equipment for machinery used in processing plates, etc., such as presses and shearing machines which are operated with great power, where, lest the operator's hands, fingers or some other part of the body be caught or cut because of an error in his operation of these machines for processing plates, etc., an insulating mat in which a wire netting is embedded is placed for supporting the operator in front of the machine for processing plates, etc., and high-frequency electric power is applied to said wire netting from a high-frequency electric power source in such a manner that a high-frequency electric field may be formed around the operator standing on the mat, that the said high-frequency electric field may be sensed by an antenna installed adequately in the vicinity of the danger zone of the machine for processing plates, etc.