The article provides the equations for calculating the harmonic current within operating band of the track receiver. It shows the fl owcharts of algorithms for determination of critical characteristics of the «broken rail» scenario and calculating of the permissible level of harmonics of the traction current of electric rolling stock with asynchronous traction motor. There is also a description of experimental verifi cation of noise-proof feature of track receivers of audio frequency track circuits. The article covers the analysis of the standards for electromagnetic compatibility of the rolling stock and track circuits and methods of its verifi cation, implemented at Russian Railways. It provides the analysis of the European standard, dedicated to electromagnetic compatibility of rolling stock and track circuits. It compares the results of processing of the records of alternating component of the traction current in the frequency and time domain.