If you’ve been paying any amount of attention to the prepping sphere for the past couple of decades, you have probably seen concern over EMPs, electromagnetic pulses, rise and rise.

sun close-up showing solar flares

Sadly, they are one of the most prevalent and pressing threats going forward, one with the potential to completely collapse society at the regional and even national level.

In less than the blink of an eye, an EMP could completely destroy the electrical grid and pretty much everything that relies on electronics in any way. It sounds like the stuff of fiction, but I assure you they are very real and have happened before. But how does an EMP destroy electronics?

An electromagnetic pulse destroys electronics by inducing a high-voltage current in any conductive material. For wires, circuits, relays, coils, and semiconductors, these components simply cannot handle the voltage spike and will either begin to melt or be burned up entirely, destroying them.

You almost certainly know what an EMP does by now, but the actual science behind it might be a foreign concept to you. But I hear you, even if you’re interested in this sort of thing, keep reading, because understanding the how of an EMP can better inform you to deal with what it will do.

I’ll explain more in the rest of this article, and then you can take appropriate action to get ready for the inevitable occurrence of such an event.

What is an EMP in Scientific Terms?

In broad scientific terms, an EMP, which again stands for electromagnetic pulse, is simply any brief burst or wave of electromagnetic energy be it artificial or naturally occurring in nature.

Using the term in its most inclusive form, EMPs can be a magnetic field, electric field, or electromagnetic field, but in practical terms, we are worried most about the most powerful EMPs.

Now, these are typically created by a collapsing magnetic field that will create and induce a correspondingly high voltage in any conductive metal within the field.

As a wave, EMPs have an extremely fast rise time and long pulse duration which means that a considerable amount of energy will be transferred.

This makes EMPs a huge threat to unprotected, complex, and low-operating voltage electronics because they will be instantly and unstoppably subjected to a high-voltage current.

EMPs Induce High Voltages to All Conductive Materials

To clarify, an EMP will induce this voltage to all conductive materials and do so basically all at once for anything that is inside the field when the emanation is generated.

This means power lines and anything connected to the power grid will be subjected to a horrendous cascade of high voltage – which will be massively destructive and can cause fires from melting and overloading.

In past events, specifically the 1859 Carrington event, telegram line operators were even shocked when it occurred! And I mean shock as in electricity, not surprised!

Worse, because the field directly affects all conductive materials any electronics that are unplugged, powered down, or otherwise disconnected will still be subjected to these damaging effects unless they are shielded or protected in some way.

As an example, your PC, television, or radio that’s plugged into your wall will be overloaded instantly or nearly so from a powerful EMP that hits the electrical grid in your area, as that voltage will flow throughout the grid, into your home, and then into all connected electronics and appliances.

But even if that PC is disconnected, the pulse will still energize those incredibly fine, sensitive circuits with voltages that they were never meant to handle.

If Something Like a Circuit Can’t Handle That Voltage, it’s Damaged or Destroyed

Like any other instance, when an electrical component or any sort of electronic goods is subjected to a high voltage spike that it isn’t designed to operate with, or has no provision for dealing with, the result is going to be damage and more often destruction.

Some materials will begin to melt. Circuits will burn out. Some components will slag entirely, and intricate electronic technology that relies on a carefully optimized and balanced interplay between different systems will be thrown horribly out of whack or just offline entirely.

Complex Electronics Use Lower Voltages and are More Vulnerable

The rule of thumb is that the more advanced and intricate the electronics, or the lower operating voltage that a device is intended to use, the more vulnerable it will be to the effects of an EMP under any given set of circumstances.

On a similar note, it’s even more important that these components or devices be appropriately protected or hardened against the effects of an EMP if you want them to survive.

Even a relatively mild EMP like a common but intense solar storm, a nearby lightning strike, or the faraway detonation of a nuclear weapon might be sufficient to destroy things like this.

Simpler, High-Voltage Circuits are Much Harder to Disrupt or Destroy with an EMP

Conversely, the simpler the device is or the higher its voltage, the less sensitive it will be to an EMP.

Fginstance, something like a simple light switch, heavy-duty extension cord, or older vehicle with little or no electronics, will do much better, often suffering no or very light damage, or else just being disrupted for the duration of the EMP.

It’s not to say you shouldn’t make an attempt to protect these devices holistically from the event, but typically you won’t have to worry about them nearly as much.

Is the Damage to Electronics Caused by an EMP Permanent?

Not necessarily.

For starters, it is possible that the damage or disruption caused by an EMP might only be temporary.

For instance, we know that in testing of more modern vehicles performed at private and national labs in the United States, once they were knocked out or rendered into a malfunctioning state by the EMP it was possible to get some of them going again.

This was done simply by turning the affected car back off and then on again. In some cases disconnecting the battery, waiting for the glitched computers to reset, and then turning the vehicle back on.

Likewise, even if electronic components in some more complicated goods are fried by an EMP, replacement of the damaged ones will likely get appliances, tools, and other gear back online.

However, the components themselves that are damaged, be they a circuit board, microprocessor, magnetic switch, wires, or anything else, are themselves probably toast. That’s because the high voltage induced by the EMP will result in actual burning, melting, or potentially even catching fire. Obviously, this is disastrous for anything so affected.

Faraday Cages Protect Equipment from EMPs But Aren’t Perfect

If this sounds like you should just get used to living without electronics post-EMP, you’re not wrong, but there are things you can do.

Certain goods can be hardened against EMPs by the use of special grounding equipment, transient voltage suppressors, or overbuilding them to withstand a sudden surge of power that they normally wouldn’t operate with.

Components may also be EMP shielded by placing them inside a Faraday cage, basically a box, sleeve, or envelope of conductive material that will intercept the EMP wave and redirect it or allow it to dissipate harmlessly before it reaches the vulnerable part.

While a great strategy, especially for parts, equipment, and gear that is small and that you don’t rely on throughout your normal life, the problem is that anything that is hooked up is still vulnerable while inside a Faraday cage…

That’s because any wire, antenna, or other piece of conductive material that leads from the equipment through the cage to the outside can pick up the EMP voltage like an antenna and then transmit it inside the cage.

Solving this problem while maintaining protection is extremely challenging, technically speaking, so Faraday cages are usually only used to protect goods that are in storage.