What Would an EMP Do?

What Would an EMP Do

by Ray K

EMP, or Electromagnetic Pulse.  Most of us have heard of it, some of us understand what it is and what it does, and those who have read “One Second After” have an idea of what will happen if we are attacked with it.  Some additional info can be found at http://en.wikipedia.org/wiki/electromagnetic_pulse

The U.S. Government created a commission to study EMP and what it could do to the safety and security of the United States.  Unfortunately, this Committee published its report the same day as the 911 Commission, so it didn’t get much news coverage.  You can read the report at www.empcommission.org.  The bottom line in the report is that it is not a matter of ‘if’ but ‘when’ we will be hit.

EMP will take out everything electronic, whether it is connected to the grid or sitting unplugged on the kitchen counter.  Things connected to the grid may fry from the 100,000-volt surge brought in through the power distribution lines.  Electronics with transistors or integrated circuits are extremely sensitive to static electricity and can be destroyed by as little as 100 volts.

Walking across a carpet and sparking to that door know is well over 1000 volts.  The surge created by the EMP in your electronic device will be sufficient to destroy them if they are not protected.

One of the committee members likened EMP to a time machine, transporting our society from ‘today’ to ‘1870’ in about one second.  We become, once again, an agrarian society, capable of supporting the level of population that we had in 1870.  This means that there will be a lot of Americans dying.

Our goal, your goal, is to be among the survivors.  There are many things that need to be done to prepare:  learning survival skills (read – What Survival Skills Does A Prepper Need), having land and gardening/preserving knowledge, and many other things.

Having communications and some of the gadgets survive could mean the difference between surviving and not surviving.  Things like solar battery chargers (see this article for solar charger recommendation), batteries, inverters, ignition systems for chainsaws, critical farm equipment electronics, walkie-talkies, NV gear among others could be critical when the time comes.

What is EMP?

When a nuclear bomb is exploded above the atmosphere, it releases gamma rays in all directions.  The ones that head towards the atmosphere strike air molecules and strip off electrons.  Those electrons and gamma rays head towards Earth, stripping even more electrons.  This avalanche of electrons called the Compton Effect, interact with the Earth’s electromagnetic field, creating very strong magnetic waves.

When a magnetic field crosses a conductor, electrical current is produced.  When this EMP magnetic wave crosses power lines, electronic equipment, anything conductive, current is produced.  Enough current could be produced to create fires, exploding transformers, extremely high voltage (current pushing through resistance results in voltage) which can break down insulation and create arcing and short circuits.

In 1962 the US detonated a 1.4 megaton bomb over one of the test sites in the Pacific.  It was high enough that the island of Hawaii, 900 miles away, had 300 street lights go out, and some microwave links were damaged.  Hours after the detonation there were still surges and ripples in the power system.  That was when we used vacuum tubes and before transistorized equipment was on the market.  Today, with microcircuits and all of the very high tech equipment that we have in our homes, our factories and our defenses, we are more vulnerable than ever.

The U.S. Senate recently stripped funds for hardening the country’s power grid against EMP from a homeland security bill.

We are on our own.

What Will Work After an EMP Attack

Will EMP harm you?  You, the human, will be safe.  Magnetic waves, even very strong ones, will not harm you.  MRIs use strong magnetic waves to make images of your innards.

But, look around you at anything with a wire or a chip.  Whatever you see, be it a toaster, TV, laptop, microwave oven, radio, chainsaw, car, or truck, it is vulnerable, and the higher the technology the more vulnerable.

WSHTF you won’t need a TV, but you will need a radio, perhaps walkie-talkies, probably solar battery chargers, that ignition coil on your chainsaw, maybe that night vision scope and whatever else you deem necessary for your survival.  EMP won’t hurt you, but it may take away most if not every electronic device that you possess.

If you are part of a group, you might consider building a larger box and sharing it, and the cost.

EMP Protection

One way to protect your gear is to build a Faraday Shielded Box and keep your stuff in it (read this article for detailed Faraday cage instructions with photos).  A Faraday shield is simply a physical device that prevents electromagnetic radiation from passing, in or out.  In our case, we’ll take a cardboard box, cover it with copper screening material, and then ground it well.

I’ll describe the one that I built and you can size it up or down as you think necessary.  Copper screen material with wire spacing of 0.1” is needed, and is the most expensive part of the project.  You can keep costs down by only making as big a box as necessary.  But when you think of the cost, think of the cost of the items that you will be protecting and what it might cost you if they don’t make it.

I started with a 2’ x 2’ x 3’ cardboard box.  I actually had two of them.  I cut the top flaps off of one and cut up the other to bend and fold a lid like a hat box, with about 2” of side overlap.  I wanted a loose fitting top, with plenty of overlap on the sides.  You don’t want any holes or gaps in the copper shielding, which is why I put the 2” flap on the lid for the box.

I laid out the screen coverage to minimize the number of lapped joints, cut the screen and used spots of hot melt glue to hold the pieces in place.  I folded the screen around lips and edges, cut and tucked it into corners, and then used a very hot (150 W) soldering iron to solder all of the lap joints and corners.  On the lid, not only cover the outside but fold the screen into the underside for the side overlaps.  You don’t want any missed areas of coverage of the screen.

Next, take a piece of bare #10 AWG or #12 AWG (house wiring Romex) and strip off the insulation.  Form it into a loop with a pigtail.  Now make a second one.  Lay one on one side flap of the lid and solder the pigtail to the screen.  Put the lid on the box and solder the other loop to the main box a couple of inches below the pigtail loop on the lid.

Your box is ready.  Find an out of the way place where it can stay undisturbed.  From the box, run a copper wire (#10 AWG) outside the house to a ground rod.  You can use a ground rod of copper or galvanized steel, or you can get 10’ of ½” galvanized pipe.

Drive it into the ground at least 8’, attach the copper wire to the clamp, and make sure that you always have the box and lid connected to the ground wire.  At the box end of the wire, use alligator clips to conned the main wire to one of the pigtails and then make a short jumper between the two pigtails.

I haven’t finished stocking mine, but my list includes night vision goggles, IR laser sight for the rifle, game camera, batteries, crank emergency radio, walkie-talkies, solar battery charger, 12V to 110 VAC inverter, ignition coil for the chainsaw and an alternator for the tractor.

Protect Your Whole House From an EMP

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  1. Long time reader, first time poster

    There is a company that did extensive testing (Sol-Ark) and created videos of the testing. Very interesting watch. Yes, part of the video was to show and market their hardware, but the real world testing using an EMP generator is still worth the watch. I am no way affiliated with sol-ark but have been following their products for a while. Basically what you are going to get from these videos is there is a good chance that as long as the electronic item is not physically connected to the electrical grid during an EMP, there is a good chance that it might survive.


  2. GREAT article! Like the man said: “An EMP will send all of us from 2019 to 1850 in a flash!”
    Just imagine the chaos in the country… no electricity, no phones, no computers, no nothing!
    And when you have eaten all the food in your cupboards, what then? Indeed….
    That’s why they call us “Preppers.” We don’t want us or our families to suffer because we
    thought it could never happen here. It can and it will! Here’s what I’m doing: I bought 5 galvanized garbage cans at Home Depot, lined them inside with cardboard
    from boxes and then placed them inside the cans to put in all my electronics. Oops! no more space. Anyhow, that’s also a good Faraday Cage.

    • AFTERNOON FROM A VERY WET SEATTLE AFTERNOON! My son says I live in a”FAIRADAY CAGE” because I have a steel roof on my house + steel siding The bad part is my cell phone in my house does not work well ! THE cell work just fine before !

  3. How about a micro-wave oven, unplugged ?

    • We tried the microwave unplugged and IMO it’s a no go. The way we tried it was to put a cell phone in it and call. If it rings then is it really a faraday cage?
      I’m not sure if this is exactly a scientific method but ……..

  4. I’ve only scanned the article and will read it in full so I many have missed something. From what I understand is that not one or even a large number of detonating nukes will wipe electronic devices throughout the country. There’s no way to calculate the coverage of an EMP. It depends on the device’s size, altitude upon detonation, number of them if multiple devices, and some degree of blockage by large buildings within and around a city. That includes mountains, hills, ridges, and even forests. Nor will there be an equally effected radius around a donation. It will be very irregular as there are so many obstructions and variables. I’m just saying the one big nuke or a number of them will not cause the whole country or even a large region to be effected.

  5. Hi to all of you out there. I just got my CD “Bullet Proof Survivor. If you haven’t gotten your copy yet, get it. This CD is a compilation of all the great articles we have read over the years. I just scanned the contents and what a list! I cannot praise this CD highly enough. Thanks MD, this is a God send.

    And by the way, I did not receive anything for this recommendation.

    • Oren Player,

      I’m glad you liked the CD – thank you! As you can tell I don’t really do a lot to promote it on the blog but I really should because more people need it.

  6. It would get people off of facebook which would be good.

  7. What happens if you are a person who can’t normally have an MRI because of an implant? What would an EMP do to you? Thank you for the informative article.

  8. Elizabeth A… An EMP will have no affect on you or your implants. The implants have no electronic components. There are other reasons why an MRI, especially of your knees, is contraindicated.

    David, a former MRI Tech

  9. Okay, on the fence here… read https://www.theorganicprepper.com/emp-hoax-or-threat/

    and this http://highfrontier.org/may-22-2018-what-me-worry/

    All in all, being a believer that the group funding the research will get the results they want, I’m on the fence.

  10. At times, it is very annoying to read articles that discuss EMP protection. Many authors assure us that a ground wire connected to the Faraday Cage is necessary, other authors calmly dismiss the need for a ground, saying that having a ground wire is actually counterproductive.

    Of course, no atmospheric test in the real world is possible. All too often the conclusion reached about the actual effects of an EMP attack is, “Nobody really knows.”

    • Survivormann99,

      So best to ground it… just to be on the safe side.

    • Survivormann99, I can attest to the effectiveness of a different type of grounding during a lightning EMP ( LEMP). An impressive strike hit outside the house. On the side of the house facing the strike, the electronics above ground level were ruined (the other 3 sides seemed to show no effect). In the lower level, facing the strike impact, the electronics below the ground grade were fine (computer, phone, printer, dvd player, clock, etc.) those above the ground grade were junk (TV, modem, router, direct tv genie, etc.). These ruined items shared surge protectors with the below grade items that were fine. There was no loss of electricity to the home, no flickering of lights, or any damage done to the home’s electrical system. I do not know how similar a LEMP is to an EMP caused by a sun burp or a bomb, but I wonder how much protection might be offered to electronics if they are kept below ground level.

  11. An EMP sends us back to 1850? ROFLMAO. We should be so lucky. How many people have horses and the requisite tack or the knowledge and skills sets to put on horseshoes ? How many people know how to make bread from scratch or mend their clothes, let alone make their own clothes? How many woodworkers have the necessary hand tools to keep doing their thing? How many people know howto garden and can their extra harvest? How many people know how to hunt, butcher and preserve their meat or make mukluks from the Hides? An EMP or CME won’t send us back to 1850, it will send us back in most ways to the stone age

    • Gulo,

      You seem to have missed the point and that is that it would send us back to 1850 technology.

      • No you missed my point. What I discussed IS 1850 ‘s technology, i.e. hand tool wood working, clothing repair with needle and thread, making horseshoes by hand, tanning hides, butchering and preserving game. Shall I go on?
        The fact that the majority of people in modern western civilization are clueless as to how to do any of that means that we won’t get to 1850 until these knowledge and skills sets are revived and practiced across society as a whole. Ergo we will generally be in an era that predates the 1850’s by hundreds of years until technology evolves to that of the 1850’s.

  12. Actually speaking about the needed skills of 1850 was a great encouragement to me as the only thing I cannot do from your list, Gulo, are shoeing horses- I’m too old, but I can show someone younger and brawnier how. I cannot sew the hides from the steers we butcher because my fingers are not as nimble at 68, but the rest of your list we do and we have supplies for on a regular basis. When I first started prepping (in 1998), I felt learning skills were more important than stockpiling food. 20 years later, not only am I “older” but hopefully wiser and better prepared with friends who have knowledge and skills that I don’t have.
    Here is hoping that I won’t need to use all of these suddenly in 2019!

  13. I can’t imagine how bad it will be if this ever happens. The children so know who are dependent on insulin are the first ones I think of.

    • I can’t imagine how bad it will be if this ever happens. The children I know who are dependent on insulin are the first ones I think of.

    • Matt in Oklahoma

      @Prepared Granny it’s bad. I’ve seen those who go down quickly just due to lack of climate control. The heat seems to be harder than the cold. Insulin is another that’s fairly quick as is many others like kidney diseases.
      Once people stop eating normal the brain cognitive functions slow way down and they can’t stay focused. Many die from mistakes like drinking bad water at this point or starve with food around them but they weren’t able to resource.
      I hope never to see it again.
      My wife herself has lupus. I’m guessing we’ve got months.

  14. Matt in Oklahoma

    @Gulo y’all are both right and I understand what you are saying. It’s one of the reasons I’ve surrounded myself with critical thinkers.
    I’ve got a lot of those skills as does my family. I lack some of those resources though.
    If there is one thing I’ve learned from good folks like MD, my Grandfathers and military leaders is that you can think and come up with solutions.
    I’ve taught my children and can’t wait till the grandkids grow outta diapers to start with them. My son has greatly surpassed me in this thinking/doing. My daughter is at least my equal and might be more.
    Best thing we can do is continue to learn new (old) things.

  15. not only will you be back to 1870….perhaps earlier, but you’ll be back to 1870 populations too.,
    i’m in the UK, the population here is the mid 18th century-when the Industrial Revolution began -was about 6 million, or one tenth(10%) of what it is in 2019.
    have a think about that.

  16. I am having a problem with the copper wire. All electricity runs thru copper wire. I know some of the old houses have aluminum wire.
    We have a microwave oven that we removed the cord from, put the cell phone in and called it. At first it rang but my son worked his magic (I don’t understand) but when we called the cell again we did not hear it ring until we opened the microwave door.
    Now we are moving on to the galvanized trash cans.