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Developed and maintained by the NFCC


Power systems

Hazard Knowledge

Personnel should be aware that the risk from electrocution or electric shock will be present until all electrical power supplies have been isolated.

It should be remembered that there may be more than one power source. These may include battery powered standby or emergency generators that activate automatically when the power supply is interrupted. It should be remembered that safety systems may have been circumvented.

It is common for there to be two separate electrical sources in a machine room:

  • 230V electrical supply for the lighting and any power sockets fitted
  • 415V electrical supply for the machinery that drives the lift, escalator or machinery