January 29, 2015

Guest Article: How to Prepare for an EMP Attack

Guest post by MobileSec Solutions.

As the founder of MobileSec Solutions LLC, an EMP protection startup, I wanted
to explain some EMP basics. My qualifications: we’ve developed the first EMP
simulator-tested laptop EMP shield that lets you protect AND USE your laptop
(including wireless). I even presented these to the top-level DoD leadership of
the nuclear strike forces in Dec 2014 to a warm reception.

General Overview - Electromagnetic pulse (EMP) is usually generated by a nuclear
detonation in the upper atmosphere. Non-nuclear explosive devices work but on a
far smaller radius. EMP has the fast rise-time E1 component (measured in
nanoseconds), the lightning-type E2 component, and the solar flare type E3
component. The most important concept here is basic physics, or the frequency
and wavelengths of the EMP waves. Higher frequencies equal shorter wavelengths.
If a wavelength is larger than the opening, it is blocked. So smaller
wavelengths need smaller openings for a blocking material to work. Therefore, in
general, if we block high frequencies, we probably block low ones too. In
practice, shielding effectiveness does not always work this way, but this is a
“good enough” explanation. EMP generates a broad band of waves ranging as high
as 10 gHz (gigahertz). We need to stop damage between ~200 mHz - 1 gHz, (mostly
E1). Above this, it becomes much harder to create damaging waves, although
theoretically possible. As wavelength decreases (and frequency increases),
eventually you get into microwave territory, so the shell of a solid object
starts to absorb the energy, not the interior electronics. The E2/E3 components
are far lower in frequency. E3 has such a long wavelength that if your devices
are unconnected to any large conductive lines (like power lines or antennae) and
are small, they should be safe from E3.

Potential EMP Sources - EMP doesn’t correlate with yield – so any size nuke can
generate an EMP. Apparently, a recent DHS study indicates that the North Koreans
actually may be able to hit the US with an EMP-optimized nuke if pressed. The
sun can generate a massive solar flare E3 pulse too.

Protective Materials - Our testing shows that copper and stainless steel make
the best shielding with all factors considered. Copper is the single "all-around
best” that is somewhat cost-effective (however, mixed materials, such as
silver-coated or copper-coated stainless steel, can perform even better). It is
very good for E3, in addition to E1 and E2, but it is also expensive and very
fragile. Stainless steel blocks higher wavelength RF energy slightly better and
is much stronger and cheaper. Interestingly, aluminum foil works too. Finally,
silver works very well, but is too expensive.

Material Configuration - For all practical purposes, material thickness is
irrelevant for EMP (almost any available material is thick enough). Solid sheets
are the absolute best. However, if visibility is needed, use many small openings
(pinholes) in the material vs. a few large ones. 100 OPI (openings per inch)
balances visibility and protection - we even use it in our products so we can
testify to its effectiveness. Above 100 OPI, visibility degrades, and below it,
protection decreases. The main issue with protective materials is creating a
solid seal around an enclosed object. Your material must contact itself all

EMP Best Practices - To minimize chances of EMP damaging your electronics, a few
basic steps will help a lot. Turn off electronics not in use. Unplug devices
that do not need to be plugged in at that time.

For your laptop – disconnect cables connected to USB or serial ports, or all ports for that matter. Our testing showed that EMP hitting USB / serial ports – pathways into the
electronics of the laptops – made the laptops much more vulnerable. Have a few
backups inside Faraday cages (electrical insulation of devices inside, we’ve
found, is actually not very important because the Faraday cage keeps all the
energy on the outside surface of the shield, not the inside). This also means
that grounding a Faraday cage is irrelevant – it just bleeds the energy out
faster, but since all the energy is on the outside, there’s no damage to your
electronics anyway. This can change if your cage is sufficiently big enough
(large room or building size) – but for small ones, it’s not a concern.

To test protective shielding, put a cell phone inside. If it cannot be called,
your shielding probably works. Assuming you followed the guidelines we laid out,
you should probably be fine. EMP can be analogized to a gunshot sound – without
protection, your hearing will be damaged. With earmuffs, you can still hear the
gunshot, but it’s no longer able to damage your hearing. By the same token, no
earmuff will help you if you are standing next to a main battle tank about to
fire – you will feel it.

For more information, please visit us at www.mobilesecsolutions.com to see our
Faraday EMP shielding, as well as our cell phone blocker to prevent tracking.


  1. Not very good discussion about EMP. Here is something better:


    Part one talks about the economic issues and that an EMP survivalists won't be better off than the rest.

    FYI: Protecting a Cell phone is pretty much useless because all of the cell towers will be knocked out. You can't use a cell phone without an intact cell network. Its not just Cell phones and computers that need protection, but also appliciances with electronics (ie refrig, stove, Solar PV, inverter, etc).

    1. I think the author meant that you can use a cell phone to test, not to use the shield for a phone.