You can protect your electronics from EMPs in a variety of ways, including faraday boxes, dischargers, and even paint. However, each of these EMP protection methods has pros and cons.
EMPs have been at the top of my mind since the EMP Commission released their report in 2008. Not only is the risk of an EMP real, but these pulses will likely occur during other disasters, like nuclear explosions. In my opinion, this fact makes them even more dangerous.
To combat this potential risk, I’ve researched dozens of potential ways to defend against EMPs. I’ll explain these below, as well as several methods that don’t work. But first, let’s take a look at what an EMP actually is.
What is an EMP?
There are two main sources of EMPs:
- High-Altitude Electromagnetic Pulse: Created when a nuclear device detonates hundreds of kilometers above the earth. (Why would someone detonate a nuclear device so high? To create an EMP and spread nuclear radiation.)
- Coronal Mass Ejection: Created by a solar flare. Unpredictable and completely random.
Both of these events would create similar results, as far as your electronics are concerned. However, the first event is a bit more troublesome, as it means you’re being attacked by someone. Plus, you’d also have radiation to contend with, as well as all the other issues that come with a nuclear explosion.
High-Altitude EMPs were first tested in 1962. During this test, a relatively small nuclear device was detonated around 250 miles above the Earth. This small explosion destroyed electrical equipment 898 miles away in Hawaii. Several more tests have occurred since then, including by the Soviet Union.
However, for one of these nuclear devices to hit the US, the country would have to be at war with someone. If someone is attacking US soil, you have bigger problems to worry about than an EMP.
Several nations have also developed “E-bombs.” These devices are non-nuclear but create an EMP like a nuclear device. They reportedly have a smaller area of effect and are deployed in combat situations. However, these weapons aren’t widespread and commonly referred to as “sci-fi weapons.” In other words, the actual risk of these weapons is very low for most people in the US. Therefore, we don’t consider them a serious risk.
Coronal Mass Ejections are normally accompanied by a solar flare. Not all solar flares cause an EMP, and not all solar EMPs are caused by solar flares. Either way, these events are unpredictable.
This sort of threat is the biggest one. Scientists put the threat of a sun-based EMP at around 1% to 3% each year. Those odds are relatively high in the grand scheme of things. Of course, these EMPs vary in size and scope. Some of them may take out the grids of whole countries, while others may just affect towns.
There are three types of EMP pulses that will occur in most EMP scenarios. These phases happen in a sequence, and you must protect your electronics from all phases.
- E1: The first phase of the EMP is emitted directly from the device or explosion. The size of this pulse will depend on the size of the weapon. In a nuclear scenario, the size of the pulse would depend on the size of the nuclear bomb and where it is detonated.
- E2: The second phase is extremely similar to lightning strikes. Luckily, most electronics are guarded against lightning strikes. Therefore, you typically don’t have to worry about this phase.
- E3: The final phase occurs when the EMP pushes off of the earth’s magnetic field. Some of the energy will be pushed back to earth, though it will have lost power at this point. The earth’s magnetic field will also be affected, potentially causing compasses and similar devices to quit working.
Nuclear explosions will typically follow these phases very closely. However, solar-caused EMPs will be a bit different. For instance, a solar EMP will not cause E1 pulses. After all, the explosion didn’t occur on earth’s surface; it occurred on the sun.
Solar EMPs will have large amounts of E3 fluctuations. They will likely be low-frequency, while nuclear EMPs will occur at both high and low frequencies.
How Do EMPs Work?
No matter where the EMP comes from, they all work the same.
EMPs create bursts of energy that instantly short-circuit electrical equipment, including computers, cars, airplanes, and radios. Streetlights and small devices may even quit working, as well. These bursts of energy affect certain electronics differently, though.
The most susceptible electronics are those with semiconductors. When this electrical energy moves through a semiconductor, it will heat up rapidly. This destroys the semiconductor and surrounding mechanisms, rendering the device destroyed. Practically all modern electronics contain semiconductors, including airplanes, cars, and military equipment.
EMPs can occur at varying frequencies. Therefore, protecting against them can be complex. You have to protect against several different frequencies at once, which is difficult to do with a single method.
Will an EMP Destroy All Electronics?
There are a lot of myths out there involving EMPs. Many preppers online outline doomsday situations where all electronics stop working as soon as the blast hits. However, the reality is much more complicated. Simply put, an EMP has not occurred at large since the world began relying on electronics for practically everything. Therefore, we don’t know exactly what electronics would be affected.
Largely, it will depend on the frequency of the EMP. Very low frequency pulses can move across power lines, allowing it to reach buildings far away. Low-frequency pulses can also penetrate the ground, reaching buried power lines and pipes.
High-frequency EMPs will affect modern computers and other electronic devices. If the pulse is very weak, the computer may just experience software errors for a short time. For instance, you may get a blue screen or loading errors. Some EMPs may be strong enough to damage the computer as a whole, though.
Either way, there is no way to determine which EMP will occur. Therefore, you have to prepare for both scenarios.
The Likelihood of an EMP
Compared to other dangerous situations, EMPs are considered pretty unlikely. While solar EMPs are more likely to occur than some other natural disasters, other EMP scenarios aren’t likely.
Let’s take a look at the likelihood of certain events that may cause an EMP:
- Solar events: As we’ve said, solar events have a 1% to 3% chance of occurring every year. However, these events may only affect a small town for a matter of minutes. There is a small chance that whole grids may be affected, though.
- Nuclear events: Low probability. These events would cause EMP surges on some level, but the size of the EMP will depend on the size of the bomb.
- Terrorists: There have been some suggestions out there that terrorists may get a hold of a nuclear device and cause an EMP. However, the probability of this is rather low.
- Microwave bombs: As we’ve stated, an EMP-specific device would be extremely rare. These devices aren’t widely available and only work over a limited area.
As you can see, a solar event is more likely to occur than any other EMP-causing scenario. Therefore, when preparing for an EMP, we recommend assuming that it’s one caused by a solar event. For this reason, the frequency will likely be lower and run through the powerlines. Surge protectors are recommended.
Methods for Protecting Against an EMP
Luckily, there are several methods that protect against most EMPs. Of course, some of these are more practical than others.
1. Faraday Cages
Faraday cages are the “traditional” method for protecting against an EMP. These work by blocking the pulse from reaching inside the “cage,” protecting the electronics within. There are expensive, commercial Faraday cages you can purchase. However, you can make an equally effective one at home with aluminum foil.
To accomplish this, you need a decent amount of aluminum foil and a cloth or paper bag. Firstly, you want to remove any batteries from the device. These may leak, rendering the device useless even if the Faraday cage works. You should also remove any antennas or other pointed parts that may make wrapping challenging. You don’t want the antenna poking through the aluminum foil.
Next, wrap the item in a paper bag or place it in a box. You can also use an envelope for small items. Make sure the device is completely covered, as you don’t want it touching the aluminum foil.
Finally, wrap each device with at least five layers of aluminum foil. For extra protection, you can also place the device in a steel trash can or other metal container. Make sure the lid makes full metal to metal contact with the container. You can use conductive metal tape between the lid and the container to help with this.
Pro Tip: To save aluminum foil and wrapping time, you can place multiple electronics in a singular cardboard box. There is no reason to wrap each device separately. You can use one large “cage.”
2. EMP Paint
As the risk of an EMP increases, several companies and government agencies have set about researching ways to defend against them. One of these newer inventions is EMP paint. This paint acts as a very thin conductor. It’s a lot like the aluminum foil in a Faraday cage – except it’s cheaper and more practical.
One of these potential products is SmartPaint. This paint was tested by the US Air Force Research Laboratory. They found that it worked great for higher frequencies. However, it didn’t work great for low-end frequencies.
Another potential product is Nanotech EMI Armour Paint, which launched recently. However, little independent testing has occurred on this paint, so I find myself a bit skeptical. Purchasing this stuff also seems to be a bit complicated. It isn’t just something you can buy off of Amazon.
I find myself in a middling ground on EMP paint. While it does work at some frequencies, more testing needs to be done to determine if it is effective. While it would be more practical than a faraday cage, EMP paint is new and largely untested.
3. Surge Protector
Surge protectors can potentially protect your home from an EMP. Sadly, we don’t know much about how a large EMP would affect the grid. Because this event has never happened before, we can only theorize about what would happen.
Potentially, if you were outside of the EMP zone, your home may still get a surge of electricity through the powerlines. The EMP surge would run down the lines, hitting your home what could be far away from ground zero. In this situation, a surge protector can be useful. Simply put, they discharge these excessive surges of energy. Having a surge protector on your home is always a good idea, but it may be a key part of EMP protection, too.
There are some surge protectors designed specifically for EMPs. For instance, the EMP Shield falls into this category.
However, surge protectors aren’t a magic bullet for EMPs. They won’t protect everything in your home in all likelihood. Furthermore, we don’t know exactly how they will work against an EMP.
With that said, these protectors will work against solar events, which would be largely low-frequency. Because this scenario is one of the most probable, it makes sense to invest in a surge protector. It may save your home from an EMP surge moving through your power grid.
At the very least, they provide some protection against lightning strikes on your home. I have had a garage door opener and a TV get zapped before from a lightning strike.
Ferrite chokes can also be installed onto wires to dampen and slow an EMP. These chokes work great when paired with a surge protector. They won’t provide much protection (probably) if you’re close to where the EMP went off but, they will assist surge protectors to protect from surges within the power lines. Many people use these chokes to protect survival equipment, like solar panels.
Ferrites are very affordable. These devices are often very easy to install, too. Some ferrites are made to simply clip onto wire bundles. Others may simply clip around individual wires. Either way, the process is usually pretty straightforward.
Things only become complicated if you use toroid ferrites, which require feeding wires through the middle. Usually, this sort of ferrite is utilized for solar power generator batteries. However, even in this case, you simply need to disconnect the lead from the battery, feed it through the ferrite, and then reconnect it.
Of course, not all ferrites are made equal. You want a size that fits your cable, though looping a cable through a large ferrite can increase effectiveness.
We recommend clipping ferrites onto all wiring going into sensitive electrical equipment. If you want it to work after an EMP, use a ferrite. However, don’t use them on high-speed lines (like area network cables), as they will slow the speed of the signal. Also, don’t use them in cars.
Methods That Don’t Work
There are a lot of misconceptions out there involving EMP protection. To protect your device from most EMP events, we recommend avoiding these methods:
Microwaves do protect against some frequencies, namely the higher ones. However, EMPs can also occur at lower frequencies. Therefore, microwaves will only work as Faraday cages sometimes.
Plus, a microwave is much more expensive than a roll of aluminum foil – and likely to be less effective. Therefore, we highly recommend just using aluminum foil as we described above. Keep your microwave for heating up food.
2. Mylar Bags
Mylar bags are often sold as tiny Faraday cages. These bags have been shown to protect against EMPs at certain thicknesses. However, everything advertised as a mylar bag isn’t going to work. It has to be a particular type of mylar bag.
Furthermore, this bag will likely be more expensive than just using aluminum foil. Again, it isn’t that there isn’t any effectiveness here, but the cost just doesn’t add up. Plus, you’d have to test the bag to ensure that it worked. At that point, you might as well just use aluminum foil.
How to Test EMP Protection Methods
We cannot test all EMP protection methods. For instance, there is no way to test whether or not a surge protector will protect your whole home in the event of an EMP. We can’t exactly set off an EMP in the middle of our house. However, we can test Faraday containers, mylar bags, microwaves, and similar containers.
Doing this is extremely simple. EMPs have a similar frequency range as FM and AM radio channels. Therefore, to test the frequency blocking power of a container, you need a handheld radio. Turn the radio to a FM frequency that comes in clear and put it into the container (or wrap it up). Make sure you turn it up so that you can hear it. If the container blocks out the FM signal, your container will likely work against high-frequency EMPs.
Now, turn the radio to an AM station that comes in clear. Wrap it up again or place it into the container. If the signal is blocked out again, the container will likely protect from a low-frequency EMP.
Of course, EMPs do have a slightly larger range. Therefore, there is always the chance that this test will give you a false positive. However, it’s the easiest way to test a Faraday cage and can be performed in only a few minutes. And, it’s pretty accurate despite the small differences in frequency.
Just because you can readily test Faraday cages doesn’t mean I recommend wrapping all your electronics in aluminum foil. There may be other, more important, prepping steps you need to take first.
Other Preparation Steps to Take
On top of protecting your equipment, there are several other steps you should take to protect against an EMP.
- Don’t connect your backup generator to the grid. If you keep a backup system in place without proper protection, a surge may affect it. Therefore, keep it disconnected until you need it. We only recommend leaving the generator connected if you have extremely good surge protection. This is another subject we will cover soon.
- Get a battery-operated radio. We highly recommend utilizing a battery-operated radio of some sort. These radios aren’t as prone to damage via an EMP.
- Don’t assume something will stop working. EMPs can affect electronics in many different ways. However, don’t assume that something will quit working just because an EMP has occurred. Once the final shockwaves have settled, try turning your phone and other electronics back on. Of course, don’t assume something will keep working, either.
- Assess the situation. EMPs occur for many different reasons. You’re in a very different situation if the EMP was caused by a nuke than one caused by a solar event. Therefore, before you start enacting your survival plan, be sure to assess why the EMP occurred. It may affect how you react. Often, this will be easier with a solar EMP, as radios and other devices may be largely unaffected.
- Food and Water. In any situation, you aren’t going to get very far without food or water. Therefore, we highly recommend having shelf-stable food on hand. During most EMPs, you’ll want to hunker down. However, this isn’t always the case.
- Bug Out Bag. During a solar event, you may be evacuated to an un-affected area. Therefore, having a bug out bag ready to go is essential. These events can vary so much, we recommend being ready to go if necessary.
What To Do Next
Prepping for an EMP involves lots of generalized preparedness, too. Check out our list of survival recipes you can make for situations without power (like an EMP). We also have a full How to Start Prepping guide to help you prepare for any emergency.