How to think about, protect against, and survive an EMP attack

Experts help you separate EMP fact from fiction, plus tips on protection and survival.

[See the full post at: How to think about, protect against, and survive an EMP attack]

  • Comments (19)

    • 9

      Wow, that was a lot to read and definitely the most complete piece I’ve read on the subject. I really appreciate the time and energy that went into this, and just as much, the objective approach. So hard to find in today’s world.

      • 6

        Thanks! We spent a lot of time trying to digest all the relevant into and make it accessible, so it’s good to hear people are finding it useful.

      • 5

        I class technologies in three tiers: EMP-Proof, EMP-Susceptible, and Post-EMP-Required, and I keep 0 backups of EMP-Proof items, 1 backup of EMP-Susceptible items, and 2 backups of Post-EMP-Required items currently, in EMP-Resistant packaging when necesary. The categories do overlap.

        Your Mileage May Vary.

        I will be using QR Codes for the inventory soon. A paper backup makes that possible because internet connectivity is EMP-Susceptible.The QR Codes must be printed with an index number.

        I do believe that the EMP potential of the high altitude targeted nuclear arsenal increases the likelihood of a first strike to an unknowd degree, and rely on the geniuses at Federation of Atomic Scientists (renamed, I think), and The Club of Rome to twiddle those probabilties, but I do what I can, and move on.

        Doug Goncz
        Experimental Machinist
        I camped at Jackass Flats site

    • 4

      If every year we have a 1% to 3% (let’s split it and go with 2%) chance of a significant sun-based EMP, shouldn’t we — statistically speaking — be seeing such events every 50 years or so, or at least once a century?

      • 6

        No, the probabilities do not add.
        At least I don’t think they do.
        I have Kemeney’s Finite Mathematics text here to check this.

      • 4

        Setting the math aside for a moment, consider that we’ve only had modern electrical grids, computers, etc. for less than 100 years, with most of that happening in the last 30-40. So some people think we’re “due” for an event, similar to how some areas are overdue for earthquakes.

    • 5

      Re:”If the EMP is solar in origin, then multiple countries may well be affected (depending on severity and angle of impact), and we could be on our own for quite a while. You can also be more confident with a solar EMP that there won’t be a nuclear exchange in the near future, so you don’t have to worry about nuclear war preps.”

      Yes, solar EMP does not affect the Far Side of the Earth, which could be any half. Note the available graphics on the 1989 Quebec blackout for more on that, via nasa.gov.

      Doug Goncz
      Experimental Machinist
      I camped at the Jackass Flats site

    • 7

      Thanks for a great article summing up the risks!  I do feel the need to correct something minor (sorry can’t help myself) – I think the quote from Kappenman about the risk of cell phones to power control systems is based on a misunderstanding.  Cell phones are not allowed next to combustion turbines for a very different reason – the possible presence of explosive gases from fuel the turbines burn.  Any electronics used in these areas need to be specially designed, tested, and certified to prevent sparking and causing an explosion under fault conditions.  I used to work on products designed for these applications.  A turbine’s control system is not at any risk from cell phone emissions, so the use of this as a comparison point is pretty meaningless.

    • 6

      Great and thorough article, congratulations. May I disagree on the likelihood of a rogue nation nuclear attack. Although I agree the likelihood of any country starting a nuclear attack is not probable, due to mutual destruction makes sense, If I were a major power I would use a small nuclear capable country for the attack knowing they would be destroyed and with the excuse of humanitarian aid, invade.

    • 6

      Great article. Thanks for the fact-based explanations. A great read on the vulnerabilities of the US electrical grid system is the book Lights Out by Ted Koppel. It’s focused on cyberattack, but the explanations of how difficult it would be to replace or repair equipment scared the bejesus out of me.

    • 6

      Excellent article, thank you; by far the most complete on the subject I’ve seen. Now here’s a question that’s been on my mind for years. My house has eight solar panels. That’s easily enough to power essential things like the refrigerator in case the grid goes down. However, the microinverters on each panel shut them off if there’s no 120V 60 Hz coming in from the electric company. I understand that’s to avoid electrocuting linemen who presumably will be working to restore power; but it also makes my panels useless just when I’d need them the most! What would it take to avoid that limitation? A bank of batteries, I’m sure, and some kind of switch to disconnect from the grid; but what else?

      • 5

        This is a very good question, and it’s one I don’t have any answer to. I’m in the market for solar, myself, and would love to know the answer. So if you come across it, please share! And if I come across it, I’ll address it in a future guide on solar. 🙂

      • 4

        Will do. Someone in my town (Bloomington, Indiana) whom I know slightly told me he has his home set up that way, but he said it was put together by a brilliant but eccentric engineer friend, and implied no one else would be likely to be able to duplicate it! Oh — and he suggested that implementing it with per-panel microinverters would be less practical than with a single inverter for the whole array. Anyway, I assumed information on a technology that doesn’t require a brilliant (even if eccentric) engineer wouldn’t be hard to find, but I’m convinced now that’s not the case, so I’ll try to find out more. Thanks.

      • 3

        I just got a long message from John, the engineer who built my aquaintance’s system. What he said in part is: “There isn’t really anything practical you can do with panels and micro-inverters.  It is possible that one day someone like Tesla will be able to do it. Basically, you’d need to fool the micro-inverters that there is a grid running to push power to.

        “I just read your question to the author of the article again.  The answer for him is to *not* use micro-inverters.  Micro-inverters definitely have their place but not if you want off grid solar power available.  From what I understand, the newer Tesla Powerwall systems will work with panels and allow off grid use.”

        He also said he could be wrong about the micro-inverters, and he’ll look around for more information.

        I don’t think I should quote John’s entire reply here, but I’d love to put you and him in touch. Could you send me your email address and I’ll try to do that? I assume you have access to mine via The Prepared to give me yours!

      • 4

        John just sent me a followup: he found an article on how to use micro-inverters for off grid power generation! It’s here: https://www.solarquotes.com.au/blog/micro-inverters-battery-backup-compatible/ . So I don’t know there’s any need for you to be in touch with him after all. That article comments “As is the case with non-micro inverter based systems, everything needs to be matched and configured properly but as one example, Enphase have a specific white paper on the issue.” That’s particularly interesting because my own micro inverters are from Enphase 🙂 .

    • 4

      Hi all, great article Jon.
      Not sure of the correct etiquette here, whether it is better to bump older threads or start a new, but I just wanted to add a couple of links for those who wanted a deeper dive on this subject.

      First is a congressional report from 2008:
      High Altitude Electromagnetic Pulse (HEMP) and High Power Microwave (HPM) Devices: Threat Assessments

      Second is a congressional report from 2019
      Electromagnetic Pulse (EMP) Protection and Resilience Guidelines for Critical Infrastructure and Equipment

      Neither of these are bite-size to do lists but like the article are pretty interesting in-depth guides. The second report is from Feb 2019 and may be related to the hearings referenced in the article.

      • 3

        Thank you for sharing the great links Pops. There sure is a lot of good information in there.

        Sharing those links here on this article was a great way to link your information where people can find it when looking at this topic. 

        If you do find an older thread where this applies you could reply on there and that will bump it back up to the top and spark some new conversations. But if the topic hasn’t been covered in a while or you have a different spin on things, you can start a new topic as well. 

    • 1

      Here’s a great and rational video showing what some of the impact would look like in the coming days or weeks after a total grid failure. It doesn’t necessarily need to be from an EMP, but even a natural disaster could cause a long term grid outage.

    • 1

      On solar events:

      1. Sounds like it would probably spare electronics, especially if not plugged in.

      2. Sounds like it might or might not affect house wiring; those built or upgraded with the new AFCI breakers (recent changes to the US National Electric Code) sound more likely to be protected, if residents don’t flip their own breakers.

      3. It’d be interesting to know how big an area could be affected and the size probability (both modern examples are far smaller than “hemisphere”), and whether it’s (as it seems, based on the two modern examples) more likely to come in though the poles. I.e., are Canada, Russia, and the Nordic countries more likely to feel the brunt?

      4. Two known modern events, both in North America? I suspect there have been others, unnoticed, elsewhere. Think Antarctica would notice? The vastness of the Pacific? The depths of Russia?

      5. It’s not entirely clear: how long do such events normally last? That might relate to how many satellites get knocked out. A full day would be a huge number of satellites.

    • 1

      Man, is it just me or is this the solar EMP thing the most terrifying/depressing thing on this site?

      The likelihood x severity x duration product of pretty much all the other prep scenarios seem to me moderate. Nuclear war is a basically permanent world-ender but seems to me a very unlikely event (it depends on people doing a really obviously crazy thing with immediate consequences and while I don’t want to be complacent….) Meanwhile a flood is maybe super likely but ultimately a temporary, localized and not catastrophic event. That kind of thing. Most of the things we deal with on this site are catastrophic or inevitable, but not both. (I know, I know, climate change.)

      But when you start talking about a thing whose probability makes it a “hundred-year event” or even a “thirty-three year event” (I know, 1% chance in a year doesn’t mean it will happen every hundred years, but that’s the language engineers and others use when describing such an event) AND whose consequences would be globally catastrophic with no recovery possible….

      I don’t know how you prepare for something like that without devoting a significant part of your life to learning pre-industrial or at least 19th-century skill sets and radical self-sufficiency.

      I’ve overreacted in the past to things like peak oil and Y2K, so I’m aware of the tendency to catastrophize. But damn. This is heavy.