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ZDNET's key takeaways

• Using an extension cord means balancing convenience and safety.
• Extension cords cause thousands of fires and tens of deaths yearly.
• Consider them a temporary solution.

We've all done it. The AC outlet is behind the couch or in the far corner of the room, but we need power here and now. So we grab an old extension cord, trail it across the floor, and before long, that temporary solution has become a permanent fixture. 

All of a sudden, your home has a fire hazard and a trip hazard rolled into one. 

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And chances are, this is not the only extension cord you have in use in your home or office.

Fire hazard, you say?

Yes. 

The Consumer Product Safety Commission (CPSC) estimates that some 4,600 home fires each year can be traced to extension cords, resulting in the deaths of 70 people and 230 injuries. And on top of the fires, there are a further 2,200 extension cord-related injuries. About half of those are shocks, and the other half are a mixture of fractures, lacerations, contusions, or sprains caused by tripping over extension cords. 

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About one of every four injuries involves children under five years of age, and half of those injuries are burns to the mouth resulting from kids chewing on the cords. 

Yes, it's bad. But let's put the dangers from extension cords into perspective so you can sleep at night (and so you don't rip them all out and throw them in the trash). 

Despite the risks, extension cords only account for about 3% of home deaths overall, and the risks are dwarfed by poisonings (accounting for around 58,000 deaths every year) and falls (a further 32,500 deaths every year). But just as you'd lock up your poisons and medicines, and try your best to eliminate trip and fall hazards, it's not a bad idea to do your best to avoid your home being consumed by flames.

The good news is that these fires and injuries are highly preventable.

The pros (and cons) of extension cords

The reason we're drawn to extension cords is that they are just so darn handy. 

The pros

You just grab one from the closet or garage, plug it in, run the cable to where you want the power, and you're done. It's a lot quicker and cheaper than hiring a professional to install a new outlet, and modern cords are packed with cool features like USB ports and surge protection that make them seem like an upgrade on the old AC outlet. 

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No wonder you find extension cords sold everywhere.

The cons

They seem perfect, but there are some big limitations that might not be immediately obvious. 

The first is that, no matter how tempting it might be to use them permanently, they're a temporary solution and not an alternative to having an electrician fit more outlets. A cord adds new failure points into the electrical system of your home or office, and the longer one is in use, the more likely it is that wear and tear will create problems.

Also: Don't plug these 7 common household gadgets into an extension cord

If you're finding yourself turning to an extension cord regularly, or you've had one in the same spot for months, it might be time to consider adding an outlet.

The other problem is that your AC outlet and extension cord each have a fixed wattage/amperage rating. Normally, you only plug one thing into an outlet, so this rating can never be exceeded, but a power strip lets you connect a whole bunch of things to a single outlet. 

On top of this, extension cords also have a maximum wattage/amperage rating, but because the extension cord outlets look like regular wall outlets, users might not realize there are limitations on what they can plug in. This makes it easy to inadvertently exceed the rating for the outlet and the cord.  

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There's then the issue of cheap, uncertified cords flooding the market. Not a week goes by that I don't come across a dangerous cord where the manufacturer cut corners in order to make a few extra pennies, potentially putting lives in danger. Only use cords listed by a recognized testing lab.

Finally, there's the matter of insurance and liability. Using extension cords doesn't automatically void your coverage, but in the event of an incident, insurers can deny or reduce a claim if it's determined the fire resulted from clear misuse or negligence rather than a genuine accident.

Then, throw in people doing dangerous things

Take the best extension cord that's ever been made and put it in the hands of Joe Average, and chances are it won't be long before they're doing shady stuff with it. 

1. First, they'll connect one (or, heaven forbid, more than one) forbidden item into the extension. This is a big NO-NO; all heavy-duty items should be plugged directly into an outlet. 
2. One of the forbidden items is another extension cord. While it might just look like "making an extension cord a little bigger," don't do it!
3. Thinking about running a cord through a wall, doorway, ceiling, or under the floor? Don't! This can cause overheating in areas you might not notice, potentially leading to an unexpected fire. 
4. Don't hide extension cords under rugs or carpets, as this can trap heat and encourage people to walk over the cable, causing damage.
5. Regarding overheating, always fully uncoil any extension cord. Cables normally heat up when in use, and when coiled, that heat can't dissipate as easily. You might argue that light electrical loads are fine on coiled cords, and I'd agree. But since most people don't know the actual wattage/amperage draw of what they're plugging into the cord, the smart advice remains -- "always uncoil the cord."
6. Never staple or nail a cord to a surface, as doing so can damage it, and it's pretty clear the cord is moving from temporary to permanent. 
7. Check your cord every time you use it, and if you notice cracked insulation, nicks or cuts, exposed conductors, or if the cord gets hot to the touch, stop using it.

My advice with a dangerous or damaged extension cord is to cut the prongs off the plug so it can't be plugged in. Don't cut the cable, as someone could still put the plug in an outlet and have live wiring exposed where the cable was cut.

Buying an extension cord? Here's what you need to know

Here's what you need to look for when buying an extension cord.

1. Only use cords listed by a recognized testing lab such as UL, CSA, or ETL. 
2. Always use a 3-wire (grounded) cord for anything with a 3-prong plug. Never (and I can't believe I have to say this, but experience suggests that I do), cut off or otherwise remove the ground pin to force fit the appliance into a 2-slot outlet.
3. If you plan to use an extension cord to power tools or garden equipment outside, make sure the cord is designed for outdoor use and plug it into a GFCI-protected outlet. 

What about "smart" extension cords? You know, the ones where you can turn the individual sockets on and off remotely? My advice: If you need to use one, connect the smart cord to a smart outlet so you can turn the entire cord off when not in use. 

When buying extension cords, you'll likely come across wire thicknesses measured in AWG (American Wire Gauge). This is a weird number because the smaller the number, the thicker the wire. So 12 AWG is thicker than 16 AWG and can therefore carry more load. 

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The minimum recommended wire gauge for a home or office extension cord is 16 AWG.

Here are some recommendations: 

• GE UltraPro Surge Protector Power Strip with USB Ports: The flat plug allows this to fit into tight spots, and the built-in surge protector offers extra safety. 
• Amazon Basics 3-Prong Extension Cord (2-pack): A cheap yet safe option. Also comes in black. 
• Cable Matters 2-Pack 16 AWG, 2 Prong, 13 Amps/1,625 Watts Extension Cord 6 Foot: Perfect for appliances such as lamps, chargers, and small electronics.
• CCCEI 12 AWG Outdoor Long Extension Cord with Multiple Outlets: This is the perfect cord for the garage or workshop, as it can handle 15A/125V/1,875 Watt loads and features a dedicated 20A circuit breaker.
• Amazon Basics 100 Foot 3-Prong Vinyl Indoor/Outdoor Extension Cord: A moisture-resistant cord that's perfect for indoor and outdoor use.
• PlugSaf 12 Foot 12 AWG Outdoor Extension Cord with Multiple Outlets Light Indicator: A super-durable cord, designed for temperatures from -40°F to 140°F, and IP65 rated dust and water resistance.
• Kasa Smart Plug Power Strip HS300: The best smart extension cord I've tested. I recommend connecting it to a smart outlet (either a standalone one or converting the outlet itself). 

Alternatives to an extension cord

Don't want to use an extension cord? Here are some great alternatives:

• Have a licensed electrician install a permanent outlet where you constantly need one. 
• A portable battery power station is a great way to provide temporary power to areas without an outlet.
• Get power banks for charging small devices like smartphones and tablets.