715 Electrical Safety for Technicians and Supervisors

Exposed Electrical Parts

If you contact exposed live electrical parts, you will be shocked.

• Wires and parts can be exposed if a cover is removed from a wiring or breaker box.
• The overhead wires coming into a home may be exposed.
• Electrical terminals in motors, appliances, and electronic equipment may be exposed.
• Older equipment may have exposed electrical parts.

Guarding. Guarding involves locating or enclosing electric equipment to make sure people don't accidentally come into contact with its live parts. Effective guarding requires equipment with exposed parts operating at 50 volts or more to be placed where it is accessible only to authorized people qualified to work with it. Recommended guarding solutions include:

• A room, vault, or similar enclosure
• A balcony, gallery, or elevated platform
• A site elevated 8 feet (2.44 meters) or more above the floor
• A sturdy, permanent screen

Warning. Conspicuous signs must be posted at the entrances to electrical rooms and similarly guarded locations to alert people to the electrical hazard and to forbid entry to unauthorized people. Signs may contain the word "Danger," "Warning," or "Caution," and beneath that, appropriate concise wording that alerts people to the hazard or gives an instruction, such as "Danger/High Voltage/Keep Out."

Knowledge Check Choose the best answer for the question.