Article updated 11/28/2023
Electrical cords and extension cords are common everywhere.
From homes to the workplace, they are one of the most commonly used and most likely abused tool that we have.
Often utilized for simple things like plugging in the space heater at work or stringing decorative lights during holidays, the easiest option for consumers is to go online or to the nearest hardware section of a store and purchase an inexpensive cord. If the price, length of cord and type of connector meet our needs, we will likely purchase the item and not think anything else about it.
Choosing an extension cord is more involved than that.
Plan ahead before buying an extension cord. Know what it will be used for and where it’s going to go. It’s also important to know how much power the equipment you’ll be plugging into it uses.
IEEE Informational Paper
Here are a few examples:
- DON’T plug extensions cords together.
- Get one that is the correct length you need. It may be tempting to just string them together, but resist the temptation. Extending the length of an extension cord by “daisy-chaining” can lead to overheating the cord by overloading it, creating a serious fire hazard.
- DON’T exceed the rating of the cord.
- This is a common mistake in offices that allow space heaters. All extension cords have wattage limits, and these limits must be respected. Again, you are looking at a fire hazard if the cord is overloaded. Some of the cheaper extension cords use internal wiring that is size 16 gauge, rated for only 10 amps. A typical 1500 watt space heater draws 12.5 amps, obviously overloading a 16-gauge extension cord. To be safe, plug the heater directly into the wall and skip the extension cord or power strip altogether.
- DON’T allow the cords to become a trip hazard.
- Spending a little extra up front on a cord that is longer but able to be stored out of the way of foot traffic is better than having someone injure himself or herself because of tripping over the cord. However, do not use metal staples or nails to secure a temporary power cord.
- Keep in mind that the National Electrical Code does not allow extension cords in lieu of permanent wiring (NEC 400.8(1) – 2014 Version). See this OSHA section ( for other restrictions as well as the following OSHA interpretation letter for more guidance. Another good interpretation letter can be found here.
And my personal favorite:
- DON’T use extension cords to connect wires in the attic or above suspended ceilings/ANYWHERE.
- These are just accidents waiting to happen. A common violation is found in the installation of ceiling-mounted electrical equipment like projectors in training and meeting rooms (as in the following photo). These locations must have a receptacle mounted flush with the ceiling with the unit’s power cord visible at all times.
e-Hazard NEC Class
Our 40-hour 2023 National Electrical Code course can train your electrical personnel to stay current with all of the electrical requirements in your facility. As we say in our electrical training classes, each person is ultimately responsible for his or her safety.