A. Automatic circuit breaking devices or fuses of the correct type and capacity shall be installed so as to protect all electric equipment and power circuits against excessive overload; however, this shall not apply to locomotives operated regularly on grades exceeding five percent. Wires or other conducting materials shall not be used as a substitute for properly designed fuses, and circuit breaking devices shall be maintained in safe operating condition.
B. An automatic circuit breaker of correct type and capacity shall be installed on each resistance grounded circuit used underground. Such circuit breaker shall be located at the power source and equipped with devices to provide protection against under-voltage, grounded phase, short circuit and overcurrent.
C. Operating controls, such as switches, starters, and switch buttons, shall be so installed that they are readily accessible and can be operated without danger of contact with moving or live parts.
D. Disconnecting switches shall be installed underground in all main power circuits within approximately 500 feet of the bottoms of shafts and boreholes, and at other places where main power circuits enter the mine.
E. Electric equipment and circuits shall be provided with switches or other controls of safe design, construction and installation.
F. Insulating mats or other electrically nonconductive material shall be kept in place at each power-control switch and at stationary machinery where shock hazards exist.
G. Circuit breakers, disconnecting devices and switches shall be marked for identification.
Code 1950, § 45-82.3; 1954, c. 191; 1966, c. 594, § 45.1-80; 1994, c. 28; 1999, c. 256.