The issues of labor protection in the process of transmission, transformation, distribution and consumption of electricity in the power supply systems of enterprises are considered. The second edition was published in 1977. The third edition was revised and supplemented with materials from PTE, PTB and GOST. For students of specialty 0303 "Power supply to industrial enterprises, cities and agriculture," it can be used by students of other electrical engineering specialties and engineering and technical workers of industrial enterprises.