# How to protect against EMPs?



## db2469 (Jun 11, 2012)

I just started researching how to protect the vulnerable electronics, batteries, etc that would be fried in an EMP attack...it seems a container of pure metal like a galvanized steel trash can will protect them...can anyone here expand on that? I just received the book "One Second After" in the mail, maybe I will learn from that as well...
DB


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## Moby76065 (Jul 31, 2012)

It's called a Faraday box. It must be grounded with a copper rod kind of deep in the ground. (5 feet)
Do a google search on it. You should consider at the least a lap top and a HAM radio. I plan on doing the same. Maybe some flash lights. Now that you mention it I think my small generator should be in one.

The Sun is the most likely place for an EMP issue. People forget we had one in the US in the 1800's that fried all the telegraph lines. I'm more affraid of Mother Nature than a terrorist EMP.

Should a massive solar flare cause another EMP on the United States there will be few repeaters so as big a unit as you can store is wise.


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## db2469 (Jun 11, 2012)

I read that the grounding rod is not needed but I'm still searching...
DB


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## Moby76065 (Jul 31, 2012)

I used to sell CT & MRI equipment. We had to build a copper sheilded room around the MRI machine to avoid outside interference. They had (the installers) copper foil that was fairly thick. I don't know where they got it however.


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## Jimmy24 (Apr 20, 2011)

db2469 said:


> I read that the grounding rod is not needed but I'm still searching...
> DB


Correct. EMP is electromagnetic. Grounding does nothing. Sheilding is what is required.

Lots of gobley-goo out there on emp. Be careful what you read. If it's not from Los Alamos or MIT or Cal Poly....I'm not gonna put much faith in most of what you read.

Just saying

Jimmy


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## Jim1590 (Jul 11, 2012)

The book is decent, ignore the forward, it isn't a teaching book, more like a wake up book, the authors ideas about how long it takes to bring things to harvest are unrealistic, his views on what would happen to the sick and ill are.

Figure out what you actually would need to protect first, then look up how to protect it. You first may want to know what parts of you car are susceptible and get spares (I have no clue if just parts would have to be protected, or the entire car)


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## db2469 (Jun 11, 2012)

JimMadsen said:


> The book is decent, ignore the forward, it isn't a teaching book, more like a wake up book, the authors ideas about how long it takes to bring things to harvest are unrealistic, his views on what would happen to the sick and ill are.
> 
> Figure out what you actually would need to protect first, then look up how to protect it. You first may want to know what parts of you car are susceptible and get spares (I have no clue if just parts would have to be protected, or the entire car)


Maybe just buy a cheap car made before electronic ignition, etc. were added and keep it filled with gas? Of course getting MORE gas might be impossible while the grid is still down...I haven't read anywhere yet any projections of how long it might be before the grid is repaired after the event...
DB


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## Jimmy24 (Apr 20, 2011)

db2469 said:


> Of course getting MORE gas might be impossible while the grid is still down...I haven't read anywhere yet any projections of how long it might be before the grid is repaired after the event...
> DB


If it's a full blown burn down of the transmission system, your are talking minimum 10-15 years. The transformers alone could be decades. The main transformer in the basic sub is a two year lead time and one year to build. My little bitty company has 93 of those along with close to 100,000 pole and pad transformers.....

It will be a while.

Jimmy


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## machinist (Jul 4, 2012)

Here's a couple links on EMP protection I stumbeld onto:
http://www.futurescience.com/emp/emp-protection.html
http://www.aussurvivalist.com/nuclear/empprotection.htm

The first one looked particularly good to me. He pretty much agrees with Jimmy24.

For transportation, I don't plan to do anything about cars and trucks. I figure that if an EMP knocks out the power grid, I wouldn't be able to get gas to drive anyway, and if I did, I'd be a BIG target. I'll look for a horse.


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## kejmack (May 17, 2011)

The 1989 Solar Flare that got Quebec fried the electric grid but it did not kill the cars and shut everything else down. I am skeptical about the apocalyptic predictions that people make about an EMP. Suppose an EMP hit one part of the country, other parts would still be able to function and send help to the stricken part.


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## db2469 (Jun 11, 2012)

machinist said:


> Here's a couple links on EMP protection I stumbeld onto:
> http://www.futurescience.com/emp/emp-protection.html
> http://www.aussurvivalist.com/nuclear/empprotection.htm
> 
> ...


Great links, thanks!
DB


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## db2469 (Jun 11, 2012)

I just saw that Amazon.com sells EMP shielding bags of different sizes...they make them sound very effective...more research is needed for me to know for sure..
DB


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## Berta (Apr 8, 2011)

kejmack said:


> The 1989 Solar Flare that got Quebec fried the electric grid but it did not kill the cars and shut everything else down. I am skeptical about the apocalyptic predictions that people make about an EMP. Suppose an EMP hit one part of the country, other parts would still be able to function and send help to the stricken part.


Unless you have gasoline stored your cars will be useless once your tank runs dry. Gas station pumps run on electricity.

One Second After is an awesome book. Replace EMP with any other major disaster and this book gives you a look at how society and humanity could react if something catastrophic occured.


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## Jim1590 (Jul 11, 2012)

I am not concerned about a solar EMP but rather a nuke launched by N Korea or Iran or some such rogue nation. Place right, it could knock out a huge part of the country.


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## forluvofsmoke (Jan 27, 2012)

Berta said:


> Unless you have gasoline stored your cars will be useless once your tank runs dry. Gas station pumps run on electricity.
> 
> One Second After is an awesome book. Replace EMP with any other major disaster and this book gives you a look at how society and humanity could react if something catastrophic occured.


Where I live, the closest gas station/convenience store now has a natural gas powdered (nobody can steal the fuel...ha-ha!) stand-by generator to run refrigeration and other critical operational equipment, including cash registers, CC readers, lighting, etc. It's a fairly large unit on a skid, maybe 35-40 KW.

Anyway, look around at the gas stations in your location for a generator. If there's one out behind the building, and it's a big unit, it may power the fuel island as well as most everything else essential to their business.

If an EMP didn't take out the controller units for gas compressor stations on the gas distribution system (limited gas supply as line pressure drops...diesel powered would be better, if it weren't for cold weather), or the generators themselves, you may still have a few places to refuel, but I wouldn't bank on it. And, as mentioned, post-event, any moving vehicle will eventually become a target, given the right location and circumstances...if you care to venture out and test your luck, you best have plenty of armor, run-flat tires and a large well organized and trained group packin' heat, and lastly, have a damn good and urgent reason for going into this potential crap-storm to begin with...not my cup of tea.

Post-EMP, there won't be much vehicle traffic if it effects modern vehicles. There also won't be much sales activities at most retailers, as they won't have the capability to function, relying solely on electrical grid, phone lines and internet, which would likely all be toasted...so, not much point in trying after the first several hours.


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## Marcus (May 13, 2012)

Jimmy24 said:


> Correct. EMP is electromagnetic. Grounding does nothing. Shielding is what is required.


The idea of grounding a Faraday cage is to remove the surface charge that has built up from the EMP on the cage itself. That surface charge remains on the cage until dissipated through whatever means.
Here's a couple of references: http://www.gamry.com/assets/Application-Notes/Faraday-Cage.pdf
http://www.thesurvivalistblog.net/faraday-cage-emp-protection/

You want to ground the cage after the EMP (think jumper cables) and before you open/enter it. You do not want a continuous ground since it may act as an antenna during the EMP. Long runs of wire act like an antenna.

Say you're putting your sensitive electronics in a plastic bag/ cardboard box wrapped in foil. Then you're putting it in another plastic bag and wrapping it in foil. You put that in a plastic bucket, and the bucket in a metal can. You've now built nested Faraday cages. Do you need to ground the metal can? No, as long as the plastic bags and bucket are non-conductive, the electronics are safe.

OTOH if you instead choose to build a basement-sized Faraday cage, you'll want to be able to connect it to a ground after the EMP since the charge can create heat.

I hope that clears it up a bit.


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## db2469 (Jun 11, 2012)

Marcus...what do you think of the EMP shielded bags for sale on Amazon.com?
DB


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## Jimmy24 (Apr 20, 2011)

Marcus said:


> The idea of grounding a Faraday cage is to remove the surface charge that has built up from the EMP on the cage itself. That surface charge remains on the cage until dissipated through whatever means.
> Here's a couple of references: http://www.gamry.com/assets/Application-Notes/Faraday-Cage.pdf
> http://www.thesurvivalistblog.net/faraday-cage-emp-protection/
> 
> ...


Sorry read nothing that clears up anything. Camrys whole business is based on noise cancelling. Not EMP. If the whole article is read, it covers earth grounding. NOT always the thing to do when dealing with high voltages differentials. Letting time happen to bleed off excess voltage is the key. You actually speak of grounding acting as antenna, which in an EMP event is exactly what you DON'T want to do. Do you know even what you need for a shield, not a bag or a 5 gallon plastic bucket. Amazon's making money how ever they can.

Faraday Cages are used for a number of things. Not just EMP issues. The bottom of electrical sub stations are grounded in such a way as to be simular to a Faraday cage, but for a total different reason. Gounding/neutral suppy for the system the sub serves and for lighting protection. Electrical, not magnetic.

Most Faraday cages used in the world, won't hold up for EMP.

As far as worrying about a nuc strike, that is by far the least of my worries. The Sun will peak in a year or two and if one thinks a solar strike is nothing to worry about, they might want to study up a bit on the Carrington Event on Sept 1, 1859. 
http://www.history.com/news/a-perfect-solar-superstorm-the-1859-carrington-event

If we get hit by a Carrington type CME we will be in the 1800s instantly. And not much we can do about it. Oh there is some talk about shutting down power before it gets here....really? 7 hours is the time it takes to get here. Not enough time.

We have many glancing blows. Satellites have been had all sorts of trouble with CMEs. So has airline comms.

The Carrington Event was WORLD WIDE. No one will be "spared" to help everyone else.

Gensets sitting at gas stations will not be a factor. Most of the hardware for starting, running and regulating a genset will be toast in an EMP event.

Now what are the chances of one getting us like that? Probably pretty slim. But for major SHTF and TEOTWAWKI it's pretty slim. But we continue to prep and hope that we never need any of our training, supplies...just like paying insurance. We pay it, but hope we never have to use it.

Hope for the best, prepare for the worst. But live your life....:beercheer:

Jimmy


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## labouton (Jan 24, 2011)

As previously mentioned, http://www.futurescience.com/emp/emp-protection.html is an excellent source of information on protection from EMP's.
Al


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## mojo4 (Feb 19, 2012)

Another item to get is a hand crank pump. They aren't too expensive and with long hoses can help "fish out" abandoned gas!! So even if the gas station is closed or abandoned you can get needed fuel. Just be sure to leave an IOU.


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## Marcus (May 13, 2012)

labouton said:


> As previously mentioned, http://www.futurescience.com/emp/emp-protection.html is an excellent source of information on protection from EMP's.
> Al


From the link:

"Much of what has been written elsewhere about faraday cages is based upon the assumption that the faraday cage is going to be a room or building sized structure. *Large professionally-built faraday cages need to be well-grounded, but for smaller faraday cages, such as you would use to shield a radio or a laptop computer, any wire running to a ground is likely to just function as an antenna, and possibly as a very efficient antenna for gathering EMP.*"

Jimmy, I believe that's pretty much what I said. Of course what do I know? I'm only an electrical engineer. I also mentioned using nested Faraday cages as is mentioned in the link. I've only designed one room-sized lab using shielding so I am not an expert.

db, I wouldn't waste money buying EMP shielded bags. You can build a nested Faraday cage cheaply using cardboard boxes and foil (two alternating layers of each as a minimum) and put it in a plastic/fiberglass bucket/box then a metal can/box. That gives you at least three layers of protection.

mojo, I also suggest getting a smaller hand pump to harvest gas from dead cars. Or you can go the brass punch and brass hammer route.


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## kejmack (May 17, 2011)

Berta said:


> Unless you have gasoline stored your cars will be useless once your tank runs dry. Gas station pumps run on electricity.


Berta, many places here in Texas have generators that run on natural gas which we have in abundance. That includes hospitals, police stations, EMS/Fire stations, grocery stores, and gas stations. You may not have gas in SC, but we will have it here in TX.


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## Jimmy24 (Apr 20, 2011)

Marcus said:


> From the link:
> 
> "Much of what has been written elsewhere about faraday cages is based upon the assumption that the faraday cage is going to be a room or building sized structure. *Large professionally-built faraday cages need to be well-grounded, but for smaller faraday cages, such as you would use to shield a radio or a laptop computer, any wire running to a ground is likely to just function as an antenna, and possibly as a very efficient antenna for gathering EMP.*"
> 
> Jimmy, I believe that's pretty much what I said. Of course what do I know? I'm only an electrical engineer. I also mentioned using nested Faraday cages as is mentioned in the link. I've only designed one room-sized lab using shielding so I am not an expert.


Ok I believe you...

Jimmy


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