# Do metal roofs protect against EMP?



## WoodsLandCamo

I guess I do not know that much about emp, but was wondering if a metal roof would protect inside electronics if the pulse was from above? is there a thickness that one should maintain?


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## PrepperRecon.com

Good question. I also wondered if an EMP would knock out a digital safe. It would be horrible to not be able to open your safe when you need the contents more than ever.


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## Leon

Short answer- with a wire connected from the tin or steel roof to the ground by means of a steel peg, connected well like a soldered wire running straight to the grounded stake, yes. This does not, however, protect from the sides but it IS indeed a 'shield from above' for an EMP.


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## dontlookatme

I always thought if u needed to protect yourself or anything, u needed to cover the entire item in a metal container. Top, bottom, sides. Think of it this way. Wind is blowing. And u are in the middle of a parking lot. There is a random door in front of you. U stand behind the door but wind still manages to get to u.


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## Lucky Jim

An old microwave would be great to store radios in-


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## AquaHull

I get no cell reception in my metal roofed and sided home.


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## Lucky Jim

I EMP-proofed my radio (below) by following instructions on the web and removing the batteries, then wrapping it in a plastic bag, then wrapping it in kitchen foil. The plastic bag is needed to stop the foil touching the radio.
I suppose a metal room or big metal container would also act like foil, protecting TV's, radios and computers inside it.


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## Smitty901

EMP much over rated threat to us. Steel roofs are a good idea no madder what they last a long time put one on the old farm house . Made a note to self never use anything but steel again.


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## Denton

EMP is no mystery. It is simply a pulse of energy propagating through the atmosphere. It travels just like a radio frequency travels, but is a blast, rather than a frequency. 
As Leon said, the idea is to block the pulse from making it to circuitry by bleeding it to ground. 

I think Top is right, too, in that the EMP threat is seriously hyped, unless you live in a nuclear targeted city. If that be the case, the EMP is only part of the problem, and I see no reason to live in a nuclear targeted place. Not nowadays, not if there is a possibility of leaving it.


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## Lucky Jim

The sun spews out solar flares which can have the same effect as an EMP, I hear 2013 will be a year of high flare activity, the earth has been zapped before-

_Sep 1859- Telegraph wires burst into flames, touching off fires .Telegraph machines scorched paper printouts, stunned operators with electric shocks, transmitted gibberish, and continued working for hours even after being unplugged from the batteries that powered them. The Earth itself was no longer "grounded"!
November 1882- another massive solar flare lit lamps, disrupted telegraph communications, and set off several fires on the Chicago telegraph switchboard, melting instruments. 
November 1903- solar storm not only disrupted telegraphs and the transatlantic cable; it even shut down Swiss streetcars. 
March 1940- severe solar storm burnt out fuses and damaged hundreds of miles of telegraph and telephone networks.
March 1989- a major solar flare shorted out Quebec's power grid. Circuits also overloaded in Great Britain, New York and Virginia. A critical transformer melted in New Jersey. 
November 2003- an "X" solar flare, the strongest of solar storms, temporarily disabled many satellites, killed one satellite completely and and burned out an instrument on a Mars orbiter. The crew of the International Space Station took shelter, reporting elevated radiation readings and "shooting stars" in their own eyes. 
September 2005- a string of "X" solar flares caused lesser disruptions to major power grids and knocked out the GPS system completely for ten minutes.
June 2011- a moderate solar flare caused minor satellite disruption, unusual amount of static on phone lines.

http://greekgeek.hubpages.com/hub/ma...lar-flare-1859 _


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## Watercanlady

Ok so we have a Metal sided garage and a metal roof. The floor is cement so how would this work??


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## Lucky Jim

Watercanlady said:


> Ok so we have a Metal sided garage and a metal roof. The floor is cement so how would this work??


It's a mystery to me, i'll keep searching around the net.
In fact I can't even figger out how an EMP could blow out car electronics if they're shielded under the metal hood, check this pulse at 2:00 that stalls everybody's cars and a guys motorsickle-


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## Denton

Just being surrounded by metal doesn't make it EMP proof.

Dang. I type to hurt my fingers. 

You have at least two people here who aren't having to scour the internet to explain it to you, and now, the other one will shut the heck up and let a movie or video help you out. Have fun. :-D


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## Denton

I'll drop a very large hint for those who never took the first class, though...
...ground.


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## shotlady

ground sirloin?

tell her what she's won, bob


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## Smitty901

EMP is not a worry for you if it gets that bad EMP will be so low on the list you won't care. It does no kill or harm people directly. Well maybe a pacemaker. 
But if you need a new roof go steel if it don't hit the fan you'll have a great roof. The old farm house.


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## Mainzer

*dontlookatme: You are exactly right!! Even if you used a GI Ammo Can as a Faraday (sp?) Cage, you would need to do something with the rubber gasket as the gasket area would be a path into the can. On "grounding" the Faraday Cage...well, there are several "schools of thought" on that. Some would say that the ground is like an antenna, just gathering the EMT into where you don't want it. Things electric aren't high on my list of skills though.*:?:


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## Lucky Jim

Mainzer said:


> ..On "grounding" the Faraday Cage...well, there are several "schools of thought" on that...


Yeah there are 'experts' all over the net arguing with each other about EMP..


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## Denton

What does the military know about EMP? Beats me. Wait, no, it doesn't.

The stake in the ground, as Leon (who knows this stuff very well) explained, bleeds the energy to ground, and away from your electronics.
When I daisy-chain wire shielding and then run a pigtail to aircraft ground, what am I doing? When the metal avionics components are "bonded" to the aircraft frame, what is this doing?

I hope you are following what I am saying. An EMP is nothing more than a pulse of unwanted energy that will enter circuitry through induction and destroy circuitry components that cannot handle such a load. Shielding and grounding protects the components from the pulse and from a static build-up. 

No mystery to this! :-D


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## Smitty901

What does the military know about EMP? Beats me. Wait, no, it doesn't. They are the ones that many years ago alerted us to it in the case of Nukes began the training, They are the ones with the weapon systems to deploy EMP as a weapon. They are the ones working to defend when others use it as a weapon. I would say they have it covered. EMP is a part of all NBC training and prep.


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## Denton

Smitty901 said:


> What does the military know about EMP? Beats me. Wait, no, it doesn't. They are the ones that many years ago alerted us to it in the case of Nukes began the training, They are the ones with the weapon systems to deploy EMP as a weapon. They are the ones working to defend when others use it as a weapon. I would say they have it covered. EMP is a part of all NBC training and prep.


Yes.
BTW, I meant that, no, it doesnt beat me. My first grasping of the notion was by Uncle Sam , 1982. EMP was an issue for us.
Now, in a different life, it is important to Sam's aircraft., and making sure the craft are not affected by emi/emp is a consideration in my job.

Didn't mean to sound as if I was belittling my paychecks.


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## PrepperThyAngus

Lots of mis-information in this thread. Let me start off by stating that I am an electrical technician by trade with over 10+ years experience. Part of my experience, and most recently, I build high voltage discharge systems. My employer uses this HV discharge systems as a plasma source. With it, along with a powerful laser beam, we generate a wake-field accelerator used in high energy physics. For those who think I am trolling or BS'ng, here is a wiki link to prove this technology exists...Plasma acceleration - Wikipedia, the free encyclopedia

Now onto the HV discharge details. These systems, which I build, discharge over 40 kilo volts. They discharge into a vacuum chamber and during moments of discharge, generate a very similar EMP to which you would see in a EMP attack or solar flare.

Now onto protection. I assure you there are two main types. Protection against EMP for grid connected electronics and protection of isolated electronics such as radios. Ever buy electronics online? The manufacturer will ship their product in anti-static/anti-EMP bags. They are metallic looking bags much like mylar. These bags, even during transit in airplanes which are susceptible to lighting EMP pulses, will be protected because the EMP pulse propagates around the bag and dissipates without entering the electronics. This concept must be applied to any EMP protection for isolated electronics. Earth grounds are NOT required. However, complete coverage of your electronics by a conducting material would shield against EMP. Keep in mind "complete" as in no rubber gasket seals in ammo cans, etc. There must be ZERO holes to allow EMP leakage into the cage. There are possibilities of using mesh screen faraday cages, like a microwave, but that only protects a certain range of frequency. To be on the safe side, keep it completely sealed.

Is grounding required? Like i said above, no. High voltage can actually propagate quite easily through the air (lightning) and through and on the surface of the ground. Grounding a Faraday cage, could increase EMP field strength around the bag or cage. For your basic isolated electronics, leave the grounds and just keep it contained 100% in metal. Thickness of metal is determined by intensity of EMP field strength. 1 layer of thin aluminum foil, could fail. I would use a few pieces of heavy duty. Using aluminum foil as a supplement to your faraday cage is recommended. Keep in mind your electronics must be isolated from the metal protecting it.

Steel roofs are not going to protect anything, neither will steel homes. Even the smallest crack will jeopardize the EMP protection integrity of the home. That space between the door and door frame? Fail. Perhaps a shipping container would work if the door frames overlap each other and leave the container completely sealed from the outside. In the day time, the less light inside would indicate a good faraday system.

Now onto grid connected electronics. Much like my HV discharge systems, all connected electronics (triggering systems, oscilloscopes to measure current pulse profile, timing systems, etc) are interconnected somehow by common grounds. The HV discharge creates an EMP, which is induced by the vacuum chamber, onto the shield of the cables, and back to the supplemental electronic systems. This causes these devices to become inoperable, or can fatally damage them. Protecting them requires a "isolation transformer" which isolates the power input from the rest of the system. We use industrial isolation transformers which can hold off up to 50kv. In addition, I must practice safe shielding to further protect other electronic systems from EMP pulse, such as cameras, motors, interlock devices, and others.

I hope this clears up some questions and mis-information. If you guys need EMP shielding advice or suggestions, let me know and I'm willing to help.


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## Denton

Yes, ESD bags and caps protect components from static build-up, but there is a reason why twisted/shielded wire is taken to air frame ground. Even the new impregnated shielded wire goes to A/C ground.

Do as you want, I'll send the pulse to ground. There is a reason why bonding is checked with the milliohmeter. I see no reason to not protect the silicon.


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## Denton

By the way, my credentials are a correspondence course in meteorology and one trip to Radio Shack.

I can remember about two types of clouds. Three, if I've had enough tequila.


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## PrepperThyAngus

Common practice of grounding is almost purely for electrical safety. EMP discharge can and most likely will (depending on strength) propagate through the ground, much like an antenna. Will this have an affect on your protected electronics? Depends on the integrity of your Faraday cage. If well designed and implemented, ground or no ground, it will remain protected.

I'm not too sure what you mean by twisted/shielded wire taken to air frame ground. Twisted/shielded cable is most often used in device networking, in which the drain wire is used to drain electrical emittance and shunt to ground to avoid inductance into the internal conductors of the cable. A/C ground, as in alternating current, must be grounded to avoid human contact of harmful electrical potential.


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## MikeyPrepper

Def a question i was going to ask. what do you think the chance is of a emp


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## Smitty901

MikeyPrepper said:


> Def a question i was going to ask. what do you think the chance is of a emp


Slim if it does and it is from a nuke I am betting you done anyway. Not something ti get to worked up about.


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## PrepperThyAngus

Solar flare and coronal mass ejection could cause one too. If the Sun is volatile , it could happen. Hard to say how likely.


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## PaulS

OK, I know this is an old thread but I have been considering the worst case with North Korea using their rockets to put a thermo-nuclear device into space and detonate it over the USA rathen to waste it on a single city. I know that extra-atmospheric blasts magnify the EMP effect. I know that EMP travels through air, water and the ground. I know that ULF also travel through the ground and that the antenna is usually underground to catch the ULF radio.

How big an area would be affected by the EMP of a low Earth orbit detonation of say.... 5mt device?


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## JPARIZ

EMP 101. I saw questions on a metal roof & digital safe. First is to understand what an EMP is... "Electromagnetic Pulse". Same as RF (radio frequency) but all over the spectrum and a burst rather than a wave. Therefore if you protect an item from RF you also protect it from EMP. A metal roof, cage, foil, box etc may not work unless it is properly grounded. Physically connected to Earth ground. A typical digital safe is metal. Simply connect a wire from the outside to ground. It "should" still function. A metal roof, even grounded won't work as the signal can go through the walls. The trick is to surround it in metal AND connect it to ground.


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## PrepperThyAngus

JPARIZ said:


> EMP 101. I saw questions on a metal roof & digital safe. First is to understand what an EMP is... "Electromagnetic Pulse". Same as RF (radio frequency) but all over the spectrum and a burst rather than a wave. Therefore if you protect an item from RF you also protect it from EMP. A metal roof, cage, foil, box etc may not work unless it is properly grounded. Physically connected to Earth ground. A typical digital safe is metal. Simply connect a wire from the outside to ground. It "should" still function. A metal roof, even grounded won't work as the signal can go through the walls. The trick is to surround it in metal AND connect it to ground.


This is untrue. Please read my post #22. Earth ground is not required. EMP is not the same as RF transmission. RF transmission is a transmitted electrical signal. EMP is a high voltage discharge which induces electrical currents.

Despite what others might think about digital safes, if your keypad or human interface is metal, it might have a possibility of surviving a local EMP. However, if the keypad or interface is plastic or has significant gaps, the EMP pulse will propagate between those cracks or plastic and damage the electrical circuits. This will lead the safe unable to open.

RF and EMP pulse do have similarities but are not the same. EMP pulse, the ones to worry about, are much stronger in magnitude and frequency range.


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## JPARIZ

PrepperThyAngus said:


> This is untrue. Please read my post #22. Earth ground is not required. EMP is not the same as RF transmission. RF transmission is a transmitted electrical signal. EMP is a high voltage discharge which induces electrical currents.
> 
> Despite what others might think about digital safes, if your keypad or human interface is metal, it might have a possibility of surviving a local EMP. However, if the keypad or interface is plastic or has significant gaps, the EMP pulse will propagate between those cracks or plastic and damage the electrical circuits. This will lead the safe unable to open.
> 
> RF and EMP pulse do have similarities but are not the same. EMP pulse, the ones to worry about, are much stronger in magnitude and frequency range.


I stand corrected. Thanks.


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## PrepperThyAngus

oswegoscott said:


> You're wrong about gaps. The wave is too long to get through steel mesh or gaps in a steel box


You're statement is too general. How do you know the wavelength of an EMP? What is too long of a wavelength? There are many sizes of steel mesh so which are you referring to? Is your statement a guess or based on experimental evidence?


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## PrepperThyAngus

oswegoscott said:


> I'm replying to your statement that there can be no gaps in order to protect. Also,grounding IS needed


I'm sorry but you are seriously misinformed. I did not ask you what you are replying to, I asked you what are you referencing to disclaim my experimental evidence as per post #22. Grounding to earth will not help disperse EMP. An EMP burst can and will travel along the ground of the earth (even into the soil itself) and travel along your "earth ground" into your faraday cage, through the ground wire. In a high energy EMP pulse, grounded equipment is more susceptible to damage than equipment in fully contained faraday enclosures.

When you buy electronics and they are packaged in electrostatic discharge bags, those achieve the same affect and you would want from a faraday cage. Are those electronic bags grounded? NO. Military standard is to transport in fully contained metallic bags. EMP burst will propagate around the bag and dissipate without entering the contents of the bag. No grounds needed.

If your going to dispute claims of an actual scientist, at least claim the source of your statements or findings.


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## JPARIZ

So there! LOL
FYI... Don't beat around the bush, just say what you mean and don't sugar-coat it this time.
Just kidding guys, jumping back in before there is bloodshed.


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## JPARIZ

oswegoscott said:


> Listen,pal--Faraday himself specified grounding.. And the bags are for static electricity. And 1/2" wire mesh is sufficient as long as it's continuosly connected & grounded


How did you know his real name was Pal?


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## PrepperThyAngus

Sorry for the narrow text. This is an excerpt from "The effects of Nuclear Weapons"
Compiled and edited by Samuel Glasstone and Philip J. Dolan, 3rd edition.
Prepared and published by the United States Department of Defense
and the Energy Research and Development Administration

Chapter 11

11.34 A few of the practices that
may be employed to harden a system
against EMP damage are described
below. The discussion is intended to
provide a general indication of the tech-
niques rather than a comprehensive
treatment of what is a highly technical
and specialized area. Some of the
methods of hardening against the EMP
threat are shielding, proper circuit
layout, satisfactory grounding, and
various protective devices. If these
measures do not appear to be adequate,
it may be advisable to design equipment
with vacuum tubes rather than solid-
state components, if this is compatible
with the intended use of the equipment.
11.35 A so-called "electromagne-
tic" shield consists of a *continuous
metal, e.g., steel, soft iron, or copper,
sheet surrounding the system to be pro-
tected*. Shielding of individual components
or small subsystems is generally
not practical because of the complexity
of the task. Good shielding practice may
include independent zone shields, *sev-
eral thin shields rather than one thick
one*, and *continuous joints*. *The shield
should not be used as a ground or return
conductor*, and s*ensitive equipment
should be kept away from shield
corners*. Apertures in shields should be
avoided as far as possible; doors should
be covered with metal sheet so that
when closed they form a continuous part
of the whole shield, and ventilation
openings, which cannot be closed,
should be protected by special types of
screens or waveguides. In order not to
jeopardize the effectiveness of the
shielding, precautions must be taken in
connection with penetrations of the
housing by conductors, such as pipes,
conduits, and metal-sheathed cables.

11.38 Good grounding practices
will aid in decreasing the susceptibility
of a system to damage by the EMP. A
"ground" is commonly thought of as a
part of a circuit that has a relatively low
impedance to the local earth surface. A
particular ground arrangement that sa-
tisfies this definition may, however, *not
be optimum and may be worse than no
ground for EMP protection.* In general,
a ground can be identified as the chassis
of an electronic circuit, the "low" side
of an antenna system, a common bus, or
a metal rod driven into the earth. The
last depends critically on local soil con-
ditions (conductivity), and it may result
in resistively coupled currents in the
ground circuit. A good starting point for
EMP protection is to provide a single
point ground for a circuit cluster,
usually at the lowest impedance element
-the biggest piece of the system that is
electrically immersed in the earth, e.g.,
the water supply system.


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## PrepperThyAngus

It would seem even the US Dept of Defense has contradictions in the use of grounding to shield against EMP. If they are not sure, who is? It all depends on your grounding quality, and EMP pulse magnitude and frequency range. However, EMP pulse range can be low hertz to megahertz. However, if one were to reach into the gigahertz, it will penetrate metal mesh. 

I would rather be safe than sorry and fully enclose my electronics. This is the same mentality my employer uses as in regards to our experiments in Post #22. We could cheap out and use metal mesh to protect against EMP but we don't want to take the risk of being wrong and damaging thousands of dollars of equipment. We use fully enclosed Hoffman brand enclosures.


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## Montana Rancher

PrepperThyAngus said:


> Grounding to earth will not help disperse EMP. An EMP burst can and will travel along the ground of the earth (even into the soil itself) and travel along your "earth ground" into your faraday cage, through the ground wire. In a high energy EMP pulse, grounded equipment is more susceptible to damage than equipment in fully contained faraday enclosures


Wow, don't know how I missed this thread but if you are still interested in some questions.

My understanding was that the earth acts as a sink to electricity, not a conductor. I realize that the ground will be hit by the same energy from the EMP, but won't the ground absorb the energy rather than conduct it? I always assumed buried electronics would be safer than above ground for this reason. Obviously the energy would eventually disperse but how far under ground would the equipment have to be?

Second, I have my main cage sitting on concrete in my basement, if grounding is bad, should I have it up on a rubber matt or something?

Third, I did a little improving on my gun safe by sealing my door around the fire proof seal with metal hoping to protect my electronic optics, but the safe also sits on concrete and is bolted down as well, will that give the emp burst a way in?

Thanks for any input you can provide.


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## PrepperThyAngus

Montana Rancher said:


> Wow, don't know how I missed this thread but if you are still interested in some questions.
> 
> My understanding was that the earth acts as a sink to electricity, not a conductor. I realize that the ground will be hit by the same energy from the EMP, but won't the ground absorb the energy rather than conduct it? I always assumed buried electronics would be safer than above ground for this reason. Obviously the energy would eventually disperse but how far under ground would the equipment have to be?
> *Both, during moments of EMP discharge the charge will actually stay on the surface of the ground until it dissipates. It will not absorb discharge completely and immediately. How long will it until it dissipates? That depends on the intensity of the discharge, humidity, and many other factors im sure. Burying your electronics underground would help shield against EMP but I cannot comment how deep to bury it. I would guess anything over 3 feet would be sufficient. The "effects of Nuclear Weapons" can probably give you a better idea, chapter 11. Also, using a Faraday cage might be more effective than burying, plus you will have easy access to your equipment.*
> 
> Second, I have my main cage sitting on concrete in my basement, if grounding is bad, should I have it up on a rubber matt or something? *It probably wont matter as long as you have a proper Faraday cage built. There should be no gaps and if you use mesh, it should be a very fine mesh. Your electronics inside must also be insulated from the cage itself. Grounded or not grounded, they should be protected with a well build cage.*
> 
> Third, I did a little improving on my gun safe by sealing my door around the fire proof seal with metal hoping to protect my electronic optics, but the safe also sits on concrete and is bolted down as well, will that give the emp burst a way in? *That must be evaluated by analyzing the safe closely. If the door seam clearance is very small and a metallic gasket is used, I can see it being a good Faraday cage. If it is mechanically locked, it will be more resistant to EMP than electronic locking keypad.*
> 
> Thanks for any input you can provide.


Please see my comments in bold.


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## Montana Rancher

Thanks a lot, that clears things up a bunch.

I was going to mention that if it is a CME that causes the problem, it is worth waiting for a few hours/days before breaking open your storage, the CME's are not like a pulse but more like a storm that can last a long time.

Is there any easy way to check the severity without modern electronics?


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## rickkyw1720pf

Seems that everyone equates EMP with static discharge. They are two different thing entirely. Unlike a static discharge where components can be easily protected by grounding and thin anti-static bags, An electromagnetic pulse destroys components by producing an electric current in the wires and metal itself. Take an anti-static bag an put a compass in it and see how much difference it makes around a magnet.


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## PaulS

The severity of solar storms is easy to check with your eyes. If you can see an aurora then it is severe enough to protect your gear and disconnect yourself fromthe outside power. EMPs only last a few microseconds but pack a lot of voltage and even more amperage. Ricky is mostly right on with his assessment but a bit off in his understanding. The EMP is caused by the electromotive force of electrons jumping from and then cascading back to their original "orbits" around the nucleus of the atoms. This generats a current than moves through everything air, water, and the ground and the only way to protect something from it is to wrap it in something that insulates it from electricity and then encase that in a conductor that lets the electrical charge go around it. No grounding rods please! a ground rod is an antenna that will give a path from the ground up along the ground wire to whatever you are trying to protect. Just take a metal box with an overlapping, tight fitting, lid and insulate the interior with anything that will resist a few hundred volts. Wrap your electronics in insulating material and place them in the box. Close it up and then use the foil (200 mph) tape around the seams and lid to make sure it is completely sealed.


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## Anthonyx

I saw a movie wherein an underground TN blast knocks out a helicopter but not a humvee because the bad guys switched off the engine.

During the Nevada tests a fleet of cars was parked around a shot tower. All but those with severe blast damage started up and drove away after the shot. EMP requires that the blast be above the atmosphere.

The only ones to test EMP over land were the Soviets. There are two pulses in an EMP; the first is a very high freq pulse moving so fast that it gets through surge protectors before they can close. This pulse will come through the grid and toast any device plugged in to the grid, shielded or not. If the device is on - it is gone. It will also flux through the atmosphere along magnetic lines - this means that even though hills and buildings can block this pulse, it is possible for it to go around these blocks depending on the magnetic field of the area.

One area that is shielded from EMP is directly under the event, due to the blast's interaction with Earth's magnetism (this is tricky to explain).

As correctly pointed out, the way that EMP does resemble RF (but not in all ways) is that it requires an "antenna". This is all the wiring in a device - if that wiring is very light and not particularly long it will suffer less impact than a heavy long wire. EMP is like radar. When it hits a target it doesn't "bounce off" it generates energy in the target, and the target then sends out a wave of its own. It does the same in any electrical device; it hits, then generates energy in the device - this what damages the device.

The Soviet tests revealed that the real "killer" in EMP is the second low freq pulse. This penetrated the ground and hit shielded cables. Like a wire moving through a magnetic field a current was generated that actually destroyed a power plant hundreds of miles away. The pulse was thousands of volts. This pulse will penetrate hills and large structures - unlike the first pulse. The EMP can be below the horizon but the slow pulse will travel over it.

Which brings up the operant point: the EMP will generate huge currents in both aboveground and buried power lines. Since the US grid is vast, the currents will be _enormous_. Again - the longer the wire exposed to the pulses, the larger the generated current. Superfast fuses can block the slow pulse, but the fast pulse will damage transformers and knock down the grid - where some devices like a digital watch survive.

I've seen no estimates of what current the vast grid of this country would generate but it would dwarf those of the Soviet tests.

There could be areas where the effect on vehicles could be minimal - or a total wipeout. However the damage will come through your household receptacles - when the voltage jumps from 110 to thousands of volts. If those are inside any cage you use for shielding the pulse will enter it.


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## paraquack

We've gone thru all the opinions before. These are written by people with the right letters after their names. Read these first. Please.

Electromagnetic Pulse - EMP Myths - futurescience.com
Protecting Your Electrical Equipment from Solar Flares
How Faraday Cages Work - HowStuffWorks
Super Electromagnetic Pulse Weapons - Futurescience.com
http://www.deepspace.ucsb.edu/wp-content/uploads/2013/01/Effects-of-Nuclear-Weapons-1977-3rd-edition-complete.pdf
EMP Effects on Vehicles - Futurescience.com
Electromagnetic Pulse - EMP Myths - futurescience.com
http://www.ferc.gov/industries/electric/indus-act/reliability/cybersecurity/ferc_meta-r-320.pdf
http://www.futurescience.com/emp/ferc_meta-r-321.pdf
Electromagnetic Pulse Protection - EMP - Futurescience.com

If you want more I got plenty of other sites and links.


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## paraquack

By the way, try this in your microwave oven. Take a good portable radio, tune in a good, strong station, keep the volume up high. Put it in the microwave and close the door. Guess what, no difference. If you tried your cell phone like I did and found that it went "dead", the reason is the cell phone output is less than 500 milli Watts and most likely less than 250 mW. An HEMP would be like an A bomb going off compared to a sneeze.


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