Surge Protector and Power Strip Safety

Surge Protector and Power Strip Safety

Did you know that power cords and surge protectors have a limited lifespan? It’s true! With continuous use, these products gradually become less effective, so you should try to replace them every 3–5 years. If this is a shock (ha ha), you’re not alone. There are a lot of not-so-obvious dos and don’ts when it comes to electrical safety, so let’s review with a surge protector and power strip rundown.      

Safety Basics

We’ll start with some basic information about power cords and work our way into the nitty gritty.

What is the difference between a power cord and an extension cord?

There is no difference between the two. Power cords and extension cords can be used interchangeably to describe any cord that connects devices to distant outlets.

How long should a power cord be?

Power cords experience a voltage drop proportional to their length, so longer power cords have larger drops than shorter ones. There are voltage calculators online to help determine your voltage drop. You should always try to use the shortest cord that meets your needs for both safety and efficiency. Shorter cables are also less likely to tangle or become tripping hazards, which leads to a safer workspace. 

What is the difference between a 3-prong and 2-prong plug?

3-prong electrical plugs are grounded to prevent electric shocks, while 2-prong plugs are not.

Are 3-to-2 prong adapters safe to use?

Yes, 3-to-2 prong adapters are safe to use. To adapt a 2-prong outlet for a 3-prong plug properly, make sure that the small metal tab on the bottom is grounded under the outlet’s faceplate screw. Leaving the metal tab exposed (on top of the faceplate screw) offers no grounding protection. Never remove the grounding prong on a 3-prong plug to fit a 2-prong electrical outlet.

3-2 prong adapters have a small metal tab on the bottom that is used for grounding.
3-2 prong adapters have a small metal tab on the bottom that is used for grounding.

What is daisy-chaining?

Daisy-chaining is when multiple devices are plugged into and drawing power from a single socket. Some examples include plugging multiple extension cords into each other or plugging an extension cord into a power strip instead of a wall socket. Although the name is pleasant, daisy- chaining is quite dangerous and should be avoided.    

Why is daisy-chaining dangerous?

Daisy-chaining can overload your electrical system, causing blown fuses and even fires. The fuse and extension cable are the most vulnerable points in a daisy chain, and you compound risk with every additional connection. It’s kind of like a game of telephone: every additional player makes the game more difficult.

Besides the risk of high currents traveling long distances, daisy chains are dangerous because they are easy to lose track of. Partial connections and buried cables are fire hazards that occur way more frequently than you might think. Try to recall the last time you accidentally tripped over a cable or tossed a couch cushion on an extension cord while tidying up. Little incidents can easily make a daisy chain dangerous, especially if you live with others or have pets.    

How can I use extension cords safely?

Check your power cord’s voltage rating to make sure it is compatible with your intended use. To protect against tripping hazards and avoid overheating, it’s best not to run any kind of power cord across a floor or underneath a carpet, floor, or wall covering. Never try to secure a cord using nails, tacks, staples, or any other item that could penetrate the outer insulation. Do not use old or damaged cables, and never run demanding appliances like space heaters or AC units through an extension cord. Check on your sockets and cables regularly to make sure they are properly connected and not overheating. And track the age of your cables, replacing them every 3–5 years. 

How to pick the right extension cord

We’ve mentioned different prongs and the importance of length, but there’s more to choosing the right power cord. In addition to length and grounding, you will want to consider whether the cord will be used indoors or outdoors, amperage, and gauge.

What is the difference between indoor and outdoor cords?

Outdoor cords often have a special type of insulation to protect them from sunlight, moisture, temperature changes and sub-freezing conditions, or other factors that could lead the cord to degrade and cause a potential fire hazard. Such heavy-duty cords can be used inside and out, but indoor cords should be strictly limited to those environments.

What are volts, watts, and amps?

Besides the physical characteristics, indoor and outdoor cords often have different amperage for different uses. You might be wondering, what’s amperage? We’ll tell you, but we should go over some other terms first.

  • Volts describes the speed at which electricity can move through a system. The United States electrical grid provides two different voltages: 120 volts and 240 volts. Demanding appliances like space heaters and AC units run at 240 volts, while smaller appliances run at 120 volts.

  • Amps describes the flow of the electric current through a circuit, with a larger amperage indicating a heavier flow. Appliances like AC units, refrigerators, washers, and dryers need high amperage to work safely, so you will find outlets with higher amp circuits in those parts of your home.

  • Watts describes the amount of power required to run an appliance. By multiplying the voltage and amperage, you can find the wattage of a device.  

Outdoor extension cords are designed to power demanding tools, so they naturally have a higher amperage than indoor cords. Indoor cords are usually rated to handle less amperage because they are not expected to power heavy machinery, which is why they are generally unsafe to use for outdoor activities.

Where can I find the amperage on a power cord?

The maximum amperage is usually printed on the cord itself or its UL or ETL tag. To determine if it's powerful enough to handle all the items you plan to plug in, total the amps of all items you plan to use simultaneously to ensure the cord can support your entire load.

What is the cord gauge?

Cord thickness, or gauge, is a good indicator of whether a cord can handle the appliances you want to power. On the packaging or outer insulation, there should be a series of numbers that list the cord gauge. The numbers inform the gauge of the wire and the number of conductors (wires) in the cord. A number like “12 3” means the cord has a 12-gauge diameter and 3 wires. The smaller the first number, the bigger the gauge. A cord with a larger gauge can handle a greater amount of amperage and wattage, and it will also carry power a greater distance with less voltage drop.

When in doubt, heavier cords are better. A lighter cord can overheat and become dangerous if you’re powering something that’s too demanding.

Power Strips vs. Surge Protectors vs. Surge Suppressors

Let’s move onto power strips, surge protectors, and surge suppressors. Although they often look similar, each device brings something unique to the table that might be useful in your household.

What is the difference between a power strip, a surge protector, and a surge suppressor?

Power strips and surge protectors generally offer a more permanent solution to expanding your electrical outlets. However, there are distinct differences between these multi-unit power supplies that you will want to consider when choosing between them.

  • Power strips split your outlet into multiple ports. Some power strips are equipped with a circuit breaker, which shuts everything during an internal voltage overload. After you have reduced the load on the power strip, you can reset the breaker to continue using it.

  • Surge protectors guard your electronics from an external voltage spike.

  • Surge suppressors are a lot like surge protectors, but they offer additional protection by regulating voltage in the event of a spike. Suppressors and protectors are usually more expensive than regular power strips, but the protective power is worth it if you deal with power spikes.

How can you tell the difference between a surge protector, a surge suppressor, and a power strip?

When shopping, first check for a UL logo or a similar safety certification. You’ll often see phrases like "surge protection" or "transient voltage surge suppressor," which plainly describe the device’s function.

How can you tell if a surge protector, surge suppressor, or power strip is good?

Beyond having a solid extended warranty, you need to do a bit of sleuthing to be able to tell if your device is good or not. Look for the clamping voltage measurement, which indicates the amount of voltage it will take for surge protection to kick in. The lower the number, the better the protection.

A rating in Joules shows how much energy the device can absorb from a power spike. In this case, a higher rating equals better protection.

Response time measures how quickly the unit will react to a surge, measured in nanoseconds, with a faster time meaning better protection. All this information should be included with the product packaging or listed on the device itself.

And if there’s no Joule rating, the device is probably just a power strip.

Indicator Lights, Data Line Protection, Power Conditioners, Power Distribution Units, and UPS (no, not the delivery service)

Protection and suppression are just the beginning of what you can do to monitor your power and avoid accidents. We are going to look at a few other options that have their own appeal, depending on your preferences.

  • Indicator lights are available on many power devices to help identify proper functioning. On some devices, the indicator light turns red when the circuit breaker is activated, while others use the red light to indicate that your wiring is properly grounded. If the lights on your device have gone out or are flickering, it’s time to replace it and/or contact an electrician to further troubleshoot issues with your electrical grid.

  • Line protection is another, more specialized option within the general surge protector family. These devices offer data line, coaxial, and phone line protection to guard against back door surges traveling over power lines.

  • Power conditioners serve as buffers between outlets and appliances, smoothing out voltage fluctuations as well as radio and electromagnetic interference while distributing power to your gear. They are a great option to protect expensive home theater equipment, a music studio, or an audio setup. In addition to helping prevent power-related failures, this may also minimize those annoying little glitches and lockups that don’t have an obvious cause.

  • Power distribution units, also known as PDUs, control and distribute electrical power to computer racks and networking equipment. While PDUs do not generally provide surge protection, they help to distribute amperage more efficiently.

  • Uninterruptible power supply, also known as UPS, combines surge protection with a backup battery to provide several minutes of power in the event of a blackout. This allows enough time to save your work and properly shut things down.

Other Considerations

We’ve covered the big stuff, but there are still plenty of things to consider while you look for the right power device. If you’re working in an industrial environment, for example, you probably won’t want a surge protector made from plastic because it’s not durable enough to withstand possible heat damage.

There are also power devices with neat perks like timers, rotating outlets, or sliding covers for additional protection. Don’t be afraid to think big when it comes to what you’re looking for, because chances are there’s a device that can accommodate a specific need.

As far as recommendations go, you really can’t go wrong with anything from APC, Belkin, or CyberPower.

Have you ever been saved by a power device? Do you have a favorite device or brand? Share your stories and suggestions in the Comments section, below.


Batteries in APC UPS units are easy to replace. Instructions are provided with the battery. The batteries in APC UPS units are shipped and bought with the battery disconnected. The battery needs to be connected before it is put into use. 

Hi Ralph, thanks for your comment about replaceable batteries for uninterruptible power supply (UPS) units. Indeed, these batteries are replaceable, and B&H carries a wide range of them, which can be found here: However, UPS units are distinct from more basic level surge protectors and power strips, which to my knowledge, do not have replaceable batteries. Thanks again for writing in and for reading Explora!

The problem with CyberPower units v. APC (for example) is the battery is not replaceable.  Therefore one has to replace the entire unit.  I find  a much better solution is an APC unit with a replaceable battery.  Replacement batteries are for the most part inexpensive--depending on the retail source--and in my view a much better way to go.  Recycling just a battery every 3 years or so, makes much more sense to me, than throwing away the entire unit.  I have also found that APC's software is considerably better than what comes with the CyberPower units.

Hi Henry, thanks for your comment and the insights about APC surge protector units. While you may have a very good point here, I'd definitely like to mention to readers that replacing the battery in any electrical unit should only be done by an experienced professional, ideally a licensed electrician. Furthermore, while I'm not positive, I'd expect that switching out a unit's internal battery would void any warranty protection from the initial purchase. Thanks again for posting your advice about this, and thanks as well for reading Explora!