EMP and Your Electronics

As we all know, the world we live in is filled with dangers. Trying to determine which ones we should concern ourselves with is one of the big challenges of life. Each of us see that differently, with some people going to the extreme of being afraid of everything, while others just ignore it all. But most of us fall somewhere in between.

When I was growing up, the big threat was thermonuclear war with the now defunct Soviet Union. That threat has been largely eliminated, but now we find ourselves in a new “cold war” with North Korea. While the balance of force is strongly on our side, there is one way in which Kim Jong-un might win that war. That is, to use his nuclear tipped ICBMs for an EMP attack on the United States of America.

EMP (electro-magnetic pulse) is something that was first discovered during the Manhattan Project, when the world’s first nuclear bomb was exploded. But at that time, electronics were primitive, so there really wasn’t much concern about the likely effect of an EMP. It wasn’t until the Starfish Prime experiment in 1962 that we started getting any idea of weaponizing a high altitude nuclear explosion and the EMP created by that explosion.

The result of that test was that in the latter years of the Cold War, a small percentage of our nation’s nuclear arsenal was fused and programmed for high altitude explosion over Russia, for the purpose of disrupting their communications, should nuclear war ever happen.

Today we face the risk of an EMP being used against us. Both North Korea and Iran are actively pursuing the technology necessary to hit the United States with a nuclear tipped missile. I’m sure that ISIS would love to get their hands on a nuclear-tipped missile for the same purpose. But it would actually be smarter for them to fuse those missiles for a high altitude burst over central Kansas. That way, the EMP from the blast would have a nationwide affect.

Put simply, EMP destroys electronics. There are actually four phases of an EMP pulse or four separate pulses. Each affects different types of electronics. Of these, the fourth one is the most dangerous, as it interacts with the earth’s electromagnetic flux, causing a huge energy spike in the electrical lines.

What Will Be Destroyed & What Will Survive?

The question of what will be destroyed in an EMP is one that receives considerable attention. The most common thinking is that everything electronic will be destroyed. That includes, the electrical grid, cars, airplanes (both use computers extensively), all forms of communications, and anything else you can think of, that uses electricity. However, old tube-type radios will survive.

There are two basic ways in which electronics will be destroyed by an EMP. The first is by direct electromechanical radiation. This will enter electronic devices, frying the delicate circuitry. As electronics have become more computerized and more miniaturized, they have actually become more susceptible to this sort of EMP damage.

However, some electronic devices, like cell phones, are small enough that they may not absorb enough EMP radiation to destroy them. On the other hand, desktop computers and entertainment centers have a network of copper cables attached to them. Those cables will act as antennas, attracting and absorbing the EMP and channeling it into the delicate electronics, where it will destroy them.

The second major way that EMP will destroy electronics is through a very rapid and massive electrical surge in our power lines. This will be big enough and fast enough that normal surge protectors will be useless. It will hit everything that’s connected to power lines, destroying delicate electronic devices.

Between these two methods of destruction, there is little that we can expect to see survive. However, while it is probably prudent to plan for everything being destroyed, chances are that some things will survive. Allow me to enumerate a few:


While modern cars are controlled by electronics, those electronics are underneath the car’s hood, which is usually made of metal. In fact, the majority of the car’s body is usually metal, except the bumpers. That makes it a nearly perfect Faraday Cage (more on this in a moment), protecting the car’s sensors and computer. The only way the EMP can get to them is through the windshield.

A large number of makes, models and years of cars were tested by the EMP commission, to see what effect EMP would have on them. Surprisingly, none were permanently damaged and the ones which stalled were able to be restarted, not just the pre-1970s ones that most people say will survive. So, chances are, cars will survive. What won’t survive is the ability to pump gas out of underground storage tanks.


Like cars, modern airplanes are controlled by electronics, even more so than cars are. So the assumption that the will fall out of the sky is unsurprising. But like cars, airplanes are nearly perfect Faraday Cages, protecting the delicate electronics inside. In fact, airplanes are actually hit by lightning fairly regularly, which passes across the skin and continues down to the ground, without affecting the airplane at all.

New airplane designs are regularly tested for EMP shielding as part of the design process. So there is a fairly good chance that they will survive.

Cell Phones and Tablets

As I mentioned earlier, cell phones have a good chance of surviving, due to their small size. The same can be said for tablets. Since neither are connected to a network of wires, there is not enough to attract the EMP, increasing their chances of survival. The exception would be those that are connected to chargers. However, the phone system and internet they depend on will be out of commission. So all they will be useful for is viewing the data they contain.

Solar Panels

Believe it or not, solar panels are largely unaffected by an EMP. The EMP will degrade their efficiency, but by less than 10%. Since solar panels are intentionally designed to provide more power than needed, the only time this difference would be noticed is when light levels are marginal for the panel’s operation. So, if you have solar panels, you’ll still have some electrical power.

Motor-driven Devices

Simple electrical devices, which don’t depend on solid-state electronics will most likely survive. Remember what I said about tube-type radios earlier? They can survive because they aren’t as delicate as solid-state electronics. So things like appliances will probably still work, if you have the electricity to run them. The only problem might be if they have a solid-state electronic control panel. But in a pinch, that can be bypassed to operate them.

Old Computers

In the world of computers, you don’t have to be very old to be considered old. I have a few “old” ones sitting around here. They are old in the sense that they aren’t the latest model and have been replaced by newer ones. But in reality, those older computers can do anything I need. They just aren’t as fast and don’t have as much memory.

Here’s the thing though. Most computer cases are metal, making them Faraday Cages. As long as the computer isn’t connected to the normal maze of wires, there’s no way for the EMP to get in. So, those old computers we all have sitting around, gathering dust, will probably work when the ones sitting on our desks get fried.

Protecting Your Electronics

Even with the things that can survive an EMP, the outlook is bleak for a post-EMP world. We depend on electricity for so much in our modern society. So the loss of electricity will pretty much shut down society. However, there is something that you can do.

Electronics that are shielded from the EMP will not be damaged. This shielding is done by a Faraday Cage. All that means is some sort of metal container that can conduct electricity (all metals conduct electricity). The electronics inside need to be insulated from the metal, but as long as they are, they are protected from an affects of the EMP.

This obviously means that we can’t use a Faraday Cage to protect electronics that we are using. But we can, and should, protect spares. That way, once the attack is over, we have electronics that we can use in rebuilding our lives.

One of the best and easiest ways I’ve seen of making a Faraday Cage is with a metal garbage can. As long as you line the inside with something that is non-conductive, like Styrofoam, it works. Nothing else is needed.

So, what sorts of electronics should you put in your Faraday Cage?

  • A spare solar charge controller for your solar panels
  • A spare voltage inverter, also for your solar panels
  • Spare well pump (if you have a well)
  • Any medical electronics you need
  • Communications gear, like a Ham radio
  • Two-way radios
  • A spare laptop computer or tablet, loaded with useful information, if you have one
  • Computers and electronic modules for your car, truck or SUV

This list isn’t exhaustive; but at least gives you an idea. Add to it as you like, so as to have whatever you think you’ll need in a post-EMP world.

Featured Image by Diana K, CC

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