809: Focus Four - Electrocution Hazards

Improper Use of Extension and Flexible Cords

Major Hazards

Be sure to untangle extension cords in order to help prevent snags, and abrasions.

Cords that are not 3-wire type, not designed for hard-usage, or that have been modified, increase the risk of contacting electrical current. With the wide use of power tools on construction sites, flexible extension cords are often necessary.

Because they are exposed, flexible, and unsecured, they are more susceptible to damage than fixed wiring. Hazards are created when cords, cord connectors, receptacles, and cord- and plug-connected equipment are improperly used and maintained.

To reduce hazards, flexible cords must connect to devices and fittings in ways that prevent tension at joints and terminal screws. A flexible cord may be damaged by door or window edges, staples and fastenings, abrasion from adjacent materials, or simply by aging. If the electrical conductors become exposed, there is a danger of shocks, burns, or fire.

When a cord connector is wet, electric current can leak to the equipment grounding conductor, and to anyone who picks up that connector if they provide a path to ground. Such leakage can occur not just on the face of the connector, but at any portion that is wet.

Identify the hazards in the pictures

Real-life Accident: Extension Cord Insulation - Fatality

Description of the accident. A fan connected to a 120-volt electrical system via an extension cord provided ventilation for a worker performing a chipping operation from an aluminum stepladder.

The insulation on the extension cord was cut through and exposed bare, energized conductors made contact with the ladder. The ground wire was not attached on the male end of the cord's plug. When the energized conductor made contact with the ladder, the path to ground included the worker's body, resulting in death.

What would you recommend?

Recommendation

Though it is possible to properly repair the extension cord, it is always best to replace an extension cord that is damaged. Yes, it may cost a little money to replace the extension cord. However, if you don't replace the extension cord, and it is not repaired properly a life can be lost and the company will be put at risk.

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