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Care And Use Of Electrical Systems

Use of Extension Cords

In general, extension cords are not appropriate where a permanent wiring solution is available, regardless of convenience. Extension cords should be used only for temporary purposes. When extension cords are used, the following restrictions apply:

  • Use only extension cords that are adequately rated for the intended use and environment. The rating must be denoted not only on the original package but printed on the extension cord insulating jacket. Review the capacity of the extension cord to ensure that you are staying within the cord’s power rating.
  • Extension cords may not be run through doors, windows, walls, or ceilings and may not be attached to building surfaces (i.e. walls, ceilings) by staples or other means.
  • Extension cords must be protected from damage and may not be placed in such a way that they create a tripping hazard. Do not run extension cords under carpets or any other flooring for protection that was not designed for this purpose.
  • Extension cords may not be plugged end-to-end or “daisy-chained”. Extension cords must be inspected regularly for wear, as it is especially likely around the plug. Worn or frayed cords must be removed from service and replaced. Cracks in extension cords must not be repaired with electrical tape.

Use of Power Strips

Power strips permit more products to be plugged into the same outlet. While power strips may be convenient they may create safety hazards when used incorrectly. Power strips do not increase the amount of power available to a location, but rather more access to the same electrical source. A heavy reliance on power strips generally indicates that additional wall outlets are needed. Follow these procedures when using power strips:

  • Select power strips that are properly rated for the application. For example, in a wet chemistry laboratory the power strip must be rated for corrosive and indoor wet locations.
  • Read and understand the manufacturer’s instructions and limitations on the power strip. For example, the on/off switch on the power strip may not be designed to interrupt the power of the devices plugged into the strip during normal applications.
  • Do not overload the circuit. Review the capacity of the circuit and the power requirements of all of the items plugged into it. This includes not only the items plugged into the power strip but also other devices plugged into wall outlets along the same circuit.

References and sources for information from the relevant websites and documentation of different universities, NGOs and government agencies used in the preparation of this website are provided at references.