The full-scale testing results of fixed-site recorders of electromagnetic radiation preceding failure in rocks in a mine after installation of the recorders on mobile mining equipment are presented. The threshold values of the recorded signals, coincident with failure of roof areas in mine openings are found, and the frequencies of electromagnetic noise at the totally de-energized electric equipment of working faces, and at the dead and live production equipment are estimated. The recommendations on the improvement of the recorder design and recorded data processing are given.
Kurlenya et al. (Wed,) studied this question.