There's nothing better than knowing that your valuable electronics are safe. And surge protectors give you that peace of mind for a very low price---but only if you replace them every few years. While the old surge protectors in your home may seem to function normally, they likely offer zero protection for your electronics.

UPDATE: 8/4/23

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How Do Surge Protectors Work?

Most people use the terms "power strip" and "surge protector" interchangeably. But a power strip is just a big plastic thing that gives you extra outlets. Surge protectors are much more useful---not only do they give you extra outlets, but they regulate the amount of power that your electronic devices receive.

Think of surge protectors like a pressure-release valves. When the incoming voltage is too high, they send it to ground instead of letting it hit your electronics. And if the voltage is too low, your surge protector increases resistance to keep electronics functioning normally.

So, while a surge protector can keep electronics online during a "voltage sag," they're most useful during power surges. As the name implies, a power surge sends an excess of voltage through your home wiring. This spike in voltage can destroy or damage electronic devices, and unfortunately, damaged electronics are a common source of house fires.

Surge protectors are an essential item in any home, and at the very least, you should use them to defend valuable electronics from power surges. But you can't just use the same surge protectors for the rest of your life; they need to be replaced every few years.

Surge Protection Wears Out Over Time

When surge protectors receive an excessive load of voltage (over 120 volts in the US), they reduce resistance by diverting or "shunting" energy to ground using a metal oxide varistor (MOV). But in the process of diverting this voltage, the MOV takes a pretty bit hit. It slowly wears out.

Every surge protector has a rating that describes how much excess voltage the MOV can handle. This rating is in joules---most power strips are equipped for 800 or 1,000 joules, while more expensive models can handle several times that amount.

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But this rating is cumulative; it's like health points in a video game. If a surge protector that's rated for 1,000 joules takes a 100-joule hit during a thunderstorm, it can only handle another 900 joules.

Once a surge protector's "health points" fall to zero, it no longer offers surge protection. It becomes a simple power strip that won't protect your electronics or your home.

Old Surge Protectors Are a Fire Hazard

Once a surge protector is "used up" it becomes increasingly sensitive to low voltages. And that's a problem, because it will still try to soak up excess voltage and send power to ground. If it's hit by a large power surge, it may become damaged, which creates a fire hazard. It could also overheat and immediately catch fire.

Plus, an old surge protector offers little protection for your electronic devices. These devices may become damaged due to the lack of surge protection---something that leads to more fire risks.

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And even if we ignore surge protection altogether, surge protectors tend to be crammed behind furniture and appliances. They're in the nastiest parts of your home, and they collect dust, crumbs, hair, and dead bugs---flammable stuff that slowly builds up over the years.

These are not theoretical risks. As the Consumer Safety Guide explains, functional surge protectors lower the risk of a house fire. But old or broken surge protectors are often the cause of fires. So, please replace your old surge protectors.

When Should You Replace a Surge Protector?

Unfortunately, you can't really tell when a surge protector needs replacing. Experts generally agree that you should replace surge protectors every two or three years, which is a good (though somewhat costly) rule of thumb.

And while you might think that a fancy surge protector will "last longer" than one that's only rated for 200 joules, that isn't necessarily the case. A large power surge can exceed 1,000 joules and instantaneously wear out the more expensive surge protectors in your home. A high joule rating simply provides extra peace of mind, especially for valuable or sensitive electronics.

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Now, you may notice that some power strips have a "surge protection" LED. This light will turn off (or turn on) to tell you that surge protection is no longer functioning properly. It's a useful feature, especially when paired with sensitive electronics, but it isn't 100% reliable.

When you buy a new surge protector, I suggest writing the date on its backside. That way, you'll know to replace it when it's two or three years old.

How to Recycle Old Surge Protectors

Unless you live in a region with strict e-waste laws, there's nothing stopping you from throwing old surge protectors in the trash. But that's pretty wasteful. Surge protectors contain several recyclable components, including copper, which may be reused for new electronics or home wiring.

But every city has its own recycling process. If there aren't any dedicated e-waste facilities in your area, you may need to call your city's waste department for recycling instructions. Or, you could use a website like call2recycle, earth911, or Greener Gadgets to find a recycling location near you.

My suggestion is relatively simple---go to Best Buy for electronics recycling. All Best Buy locations offer e-waste recycling and may give you a gift card if you recycle something of value.