The main fan line used for ventilation in any tunnel or underground mine classified extrahazardous shall contain a cutoff switch capable of halting all machinery underground automatically should the fan fail or its performance fall below minimum power needed to maintain a safe atmosphere.

(Added by Stats. 1972, Ch. 1430.)

Terms Used In California Labor Code 7983

  • Mine: means any excavation or opening above or below ground used for removal of ore, minerals, gravel, sand, rock, or other materials intended for manufacturing or sale. See California Labor Code 7951
  • Tunnel: means an underground passageway, excavated by men and equipment working below the earth's surface, that provides a subterranean route along which men, equipment, or substances can move. See California Labor Code 7951