Guidelines for servicing electrical equipment

You must observe the guidelines when you service electrical equipment.

For your safety, the following guidelines must be observed:
  • Check the area for electrical hazards, such as moist floors, non-grounded power extension cords, and missing safety grounds.
  • Use only approved tools and test equipment. Some hand tools have handles that are covered with a soft material that does not provide insulation from live electrical current.
  • Regularly inspect and maintain your electrical hand tools for safe operational condition. Do not use worn or broken tools or testers.
  • Do not touch the reflective surface of a dental mirror to a live electrical circuit. The surface is conductive and can cause personal injury or equipment damage if it touches a live electrical circuit.
  • Some rubber floor mats contain small conductive fibers to decrease electrostatic discharge. Do not use this type of mat to protect yourself from electrical shock.
  • Do not work alone under hazardous conditions or near equipment that has hazardous voltages.
  • Locate the emergency power-off (EPO) switch, disconnecting switch, or electrical outlet so that you can turn off the power quickly in the event of an electrical accident.
  • Disconnect all power before you conduct a mechanical inspection, work near power supplies, or remove or install main units.
  • Before you work on the equipment, disconnect the power cord. If you cannot disconnect the power cord, have the customer power off the wall box that supplies power to the equipment and lock the wall box in the off position.
  • Never assume that power is disconnected from a circuit. Check the circuit to make sure that power is disconnected.
  • If you must work on equipment with exposed electrical circuits, observe the following precautions:
    • Make sure that another person who is familiar with the power-off controls is near you and is available to turn off the power if necessary.
    • When you are working with powered-on electrical equipment, use only one hand. Keep the other hand in your pocket or behind your back to avoid creating a complete circuit that might cause an electrical shock.
    • When you use a circuit tester, set the controls correctly and use the approved probe leads and accessories for the device.
    • Stand on a suitable rubber mat to insulate you from grounds such as metal floor strips and equipment frames.
  • Use extreme care when you measure high voltages.
  • To ensure proper grounding of components, such as power supplies, pumps, blowers, fans, and motor generators, do not service these components outside of their normal operating locations.
  • If an electrical accident occurs, use caution, turn off the power, and send another person to get medical aid.