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Thread: EMP does NOT effect most autos + everything else you ever wanted to know on EMPs

  1. #41
    Administrator Rick's Avatar
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    The electronics in your car is surrounded by metal.......a great big Faraday cage. Unless you're driving a Corvette of course in which case you spent waaaay too much money to get hosed.

    I don't know about that whole meteor strike in Siberia. I read on www.truestuffonthenet.com that a local village ran out of everything to eat but Borscht so everyone in the village had Borscht for dinner. The cabbage started working overnight and the next day...Kaboom! The only thing left was one badly shaking dog and a blind donkey. Actually, the donkey wasn't really blind he was just too scared to open his eyes.


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    Well a lot of high voltage transmission lines are uninsulated, and a huge very powerful EMP could take some station transformers off line, but I doubt that a normal magnitude EMP from the sun would ever take our entire grid down. Now if they start launching nuclear EMP devices, we are in deep stuff regardless.
    I am much more worried about the economy than EMP's right now!

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    I still swear that I was hit by a EMP at the house, as when I returned for Louisiana last winter.
    Garage door opener wouldn't work, several lights out in garage, both vehicles in garage batteries were dead....What a PITA.
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    Quote Originally Posted by hunter63 View Post
    I still swear that I was hit by a EMP at the house, as when I returned for Louisiana last winter.
    Garage door opener wouldn't work, several lights out in garage, both vehicles in garage batteries were dead....What a PITA.
    Sounds like Gremlins to me (the creatures, not the cars)...

    Another thought: Does Ferris Buehler live or vacation in the vicinity?

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    Senior Member hunter63's Avatar
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    Quote Originally Posted by Daniel Nighteyes View Post
    Sounds like Gremlins to me (the creatures, not the cars)...

    Another thought: Does Ferris Buehler live or vacation in the vicinity?
    Actually just down the road.......as do the Blues Brothers......

    Gremlins were made here, and still a lot's around.......
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  6. #46

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    Kyrat
    Even where I am at there isn't a light bulb within 10km, and I certainly wouldn't test there if I do at all. And the reason I would test is that I'm not positive it would work. I know how unreliable theories are. I doubt the explosion would take out more than one or two trees. Fear of forest fire would be one of the larger concerns. Every explosion creates at least a very small emp. The trick is to magnify it. Yes Rick, there are reasons not to particularly fear man made EMPs. But that very weakness can be turned into a strength.

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    Are you uncomfortable about financial crisis, political turmoil, senseless riots, oppressive government and other world anxieties? Can our world be sustained? For a limited time see “Operation Phoenix” at www.AllenCurrie.ca for a free peek at a probable future. Quote -“A must read. If there ever was a story that predicted a very possible future this is it.”
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  7. #47
    Administrator Rick's Avatar
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    WT - It really doesn't matter if a wire is insulated or not. The only real reason for insulation is to prevent grounding or a short. Transmission lines are such high voltage that insulation wouldn't mean anything anyway. All you have to do to induce voltage is place the wire within the magnetic field of a "source". Voltage will then travel one way or the other depending on the difference in potential. You can flat get your willies knocked off if you are working underneath a transmission line whether it's TV or Phone. Remove the ground strap and you get a beautiful blue arc suitable for scarring even the older kids among us.

    We've had in depth conversations about EMP on a couple of other threads. The gist is that the only time you see damage on the grid from a solar emp event is when there is a problem with a component (broken insulator, etc). The over voltage causes problems at the location only. In the past, that has triggered systematic shut downs and associated blackouts. Those were automatic and built into the grid. A multitude of changes have been made based on things learned from past events.

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    ....and while a cascading event could take down a large area of the grid, as Rick said - changes and lessons learned will help to ensure that those outages are recoverable within a relatively short period of time.
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    Resident Wildman Wildthang's Avatar
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    Rick there are a lot of high voltage circuits that use shielded dielectric insulation, but most of those are underground, in raceways, and inside switchgear. I know that induced voltages will affect insulated transmission lines as well as bare conductors. It is the long expanses of transmission lines that help build up the magnitude of an induced voltage, by increasing the exposure to the magnetic impulse.
    Modern protective relaying will normally react very quickly when a curcuit is taken off line and return power to the grid.

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    Senior Member hunter63's Avatar
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    Personally I would be interested to know just how basic a vehicle would have to be to avoid having a possible problems with EMP.

    Now MY reasoning would be,.... say if I was to find, say... an older jeep Cj5...... with a few mods, as a BOV (yeah, that's the ticket, BOV...read fun truck here)....that I could pass off as a 'prepper gotta have"....not that I personally "need" permission, but for all those poor suckers that still have to justify a stuff like this.

    So I'm thinking a big 6, (maybe snall block v8) normally aspirated, a points and coil ignition....jack job, 36" buck-shots...ROP.......
    I'm gonna like this EMP prep........I think?

    Maybe not quite this extensive.....LOL.....
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    Last edited by hunter63; 03-27-2012 at 03:01 PM. Reason: added stuff
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  11. #51
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    Pretty darn basic.

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    I have a sheet metal pole barn, and anything parked in there would basically be immune to EMP's. So I should still have 2 motorcycles, and 2 ATV's ready to do, but I really doubt that an EMP would immobilize a car or truck in good condition.

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    Quote Originally Posted by hunter63 View Post
    Personally I would be interested to know just how basic a vehicle would have to be to avoid having a possible problems with EMP.

    Now MY reasoning would be,.... say if I was to find, say... an older jeep Cj5...... with a few mods, as a BOV (yeah, that's the ticket, BOV...read fun truck here)....that I could pass off as a 'prepper gotta have"....not that I personally "need" permission, but for all those poor suckers that still have to justify a stuff like this.

    So I'm thinking a big 6, (maybe snall block v8) normally aspirated, a points and coil ignition....jack job, 36" buck-shots...ROP.......
    I'm gonna like this EMP prep........I think?

    Maybe not quite this extensive.....LOL.....
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    Get the most basic of them all, a horse and buggy

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    Contrary to the assertion above, the power companies have not learned from past mistakes. The grid is known to be vulnerable, today. And contrary to another assertion above, we are not talking about short term power outages.

    A strategically placed high altitude EMP optimized relatively low yield nuke can create damaging emp levels throughout most of the US. You don't need three or high yield. Intense geomagnetic storms can have a similar effect. A storm capable of causing extensive damage to the power grid is highly likely within the next few decades with 2013 being particularly risky. The threat of naturally occurring "EMP" is considered greater than the terrorist/enemy state threat. The sun is the ultimate nuclear power.

    EMP or geomagnetic storms can push transformers in the power grid into saturation, resulting in their destruction. It takes around 15months to get replacement transformers, today; in the event of a widespread EMP event, it would be much worse - we would have to build new factories to make all the replacement transformers needed. It will take an estimated 4-10 years to repair the grid. Here is a map of the percentage of transformers expected to be destroyed in each state by a geomagnetic storm. Six states will only lose single digit percentages. Half a dozen states lose over half of their transformers. One state will lose 97%. My state loses 47%. Most of the east coast and northern states get hammered bad.
    http://books.nap.edu/openbook/12507/png/79.png


    A faraday cage does not necessarily have to be grounded. It does need to be fully enclosed on all sides with conductive seams and have proper conductive gaskets or metal fingers on the edges of all openings. The passenger compartment of a car is not a faraday cage (if it was, your cell phone would never work inside). Windows and lack of conductive seals on doors make it ineffective. However, the ignition system on the car is itself a source of EMP like emissions so critical car electronics tend to be designed to withstand high voltage spikes. A metal pole barn is not likely to have the gapless electrical connection needed between the walls and ground (which in this case is the bottom of the "cage") and welded seams between the walls and roof. An ammo can does not have proper conductive seal between the walls and lid. Without the proper connections between the 6 sides of an alleged faraday cage, it not only can fail to stop EMP but portions of the "cage" can act as an antenna making things worse. TV, ham radio, CB, and FM radio antennas and power lines, cable tv, and phone lines can also act as antennas bringing EMP inside even structures which are safe. A 1 meter length of wire is enough to bring 10,000 to 50,000 volts inside in an EMP event or destroy electronics inside an unshielded structure. Many connecting cables (power cords, USB, HDMI, DVI, phone, ethernet, RS-232, IEEE-488, firewire, cell phone charger, etc) are 1 meter or longer.

    The inverse square law does not cause EMP to drop off rapidly with distance as you might expect. The earth's magnetic field affects the results, among other things. Also, the effect is integrated across the height of the atmosphere. As a result, the dropoff from a high altitude burst seems to be roughly inversely proportional to distance rather than the square of distance. And the magnetic conjugate affect can cause damage at large distance similar to that under the blast.

    Most cars are expected, by a simple minded interpretation of the study results, to be able to operate after EMP after restarting and/or disconnecting battery. However, many cars being driven at the time will temporarily malfunction and this is expected to cause multi-car accidents, disabling more vehicles and blocking roads. Also, note that in testing they increased EMP until the car malfunctioned, then stopped. So the percentage of cars which continue to be operable (after restart) may be highly exaggerated since most test vehicles where never exposed to full strength EMP - especially those which were most vulnerable.

    It has been said that a broken micowave oven with the power cord cut off (cover the cord entry hole with metal foil tape) would make a good faraday cage for EMP protection of personal electronics (since it is carefully designed to contain microwaves which are particularly troublesome). I found, however, that when I put an FM radio inside my microwave oven (still plugged in) that it still was able to receive broadcast stations (inside a house with aluminum siding and metal window screens). The door seal is largely capacitive and not so effective at lower frequencies. Still, likely to be more effective than most attempts to build your own -it is almost a nested double faraday cage and is at least effective at some frequencies which is better than most lay attempts would be. Sealing the door shut with metal tape would help some as would wrapping with overlapping aluminum foil. Note that the oxide layer on aluminum interferes with a proper conductive path across seams. And paint and non-conductive tape adhesive also interfere. Better, yet, strip the paint off down to bare metal and use conductive adhesive copper tape to seal the door on all sides and cover the front panel. I did this FM radio test after an aluminum clipboard case (inside which i keep some ham radio gear) flunked a similar test, as expected (lack of EMI gasketting on lid).

    Whole house surge supressors installed in the breaker panel plus local power line surge supressors on electonics and EMP arrestors on phone lines, cable tv, and exterior ham/cb/fm/tv antennas (which all need to be brought in, grounded, and surge surpressed next to the breaker panel) with added ground rods installed at the entry point and properly connected with straps to a single point ground at the circuit breaker panel should improve your odds some in areas where the EMP is not too severe. Even so, all connections to the outside world as well as connections between equipment inside your house are a vulnerability.

    Installed photovoltaic systems, as opposed to those stored disconnected inside a faraday cage, are also at risk.
    Note that batteries need to be charged periodically, however, or they will be permanently damaged by self discharge. Even the solar cells themselves are potentially vulnerable; they are semiconductor junctions themselves and can withstand limited reverse voltage and can be damaged just by shading a portion of the array (bypass diodes help with this but are themselves vulnerable) while other portions are generating power. The panels have a large surface area to collect the falling emp charge. Charge controllers and inverters are electronic devices which can be susceptible. Long wires may interconnect parts of the system. Grid-tie systems connect to the power grid. Lightning strikes, somewhat similar to EMP, are the major cause of solar system failure. Improper grounding of the system is usually implicated. The good news is that good lightning protection design helps resist EMP but lightning arrestors may not be fast enough to protect against EMP which requires response times almost a thousand times faster.

    It is very hard to find good quality information on EMP protection - even if you are an electrical engineer.
    I am an EE and have experience with circuit design, solid state systems, high voltage, high current, high power, lightning protection, RF shielding, transformers, ham radio/emergency communications, astrophysics, satellites, military electronics, alternative energy, motor control, electric vehicles, repair, failure and reliability analysis, etc. I take the threat of EMP and geomagnetic storms very seriously.

  15. #55
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    I would humbly suggest that a nuclear device large enough to cripple the power grid would most likely leave us .... dead. In which case the grid is the least of my worries.

    I would also like to see your reference on the six months required to build a transformer. Unless your reference is to extremely large sub-station transformers and even then I'd be shocked at that time frame.

    The rest is purely hypothetical except to say that the EMPs that have caused damage to date have not caused massive damage. They generally have affected a single or a few components that were already in disrepair, which resulted in a planned and controlled shut down of the grid.

    You actually have no practical references to claim that outages will be long term since none exist. And to say that power companies (or any company) has not learned from it's past mistakes is somewhat short sited. Not only are these types of events costly in terms of repair but also in terms of lost revenue. They also draw the ire of governing bodies as well as citizen groups that force changes. My experience has been it's much easier to make the correction up front than to have to deal with state commerce commissions or the FCC, which tend to go a bit overboard.

    An outage the scale that you are talking about is never a single cause event. It is, rather, a series of events, often involving human error, that cascade into a large scale event. Here is a link to a perfect example. If you scan down the page you'll see the time line. Look at all the events that occurred that tied what should have been isolated incidents into a large scale blackout.

    http://en.wikipedia.org/wiki/Northea...ence_of_events

    Incidentally, a post mortem is generally conducted on any large scale event in order to determine the cause(s). That post mortem will also include corrections to preclude future events from occurring.

    Finally, your reference to surge suppressors, even following single point grounding in accordance with federal electrical standards offer little protection against anything other than minor voltage fluctuations, which is what they were designed for. Lightening or a large emp event of any source can and will overwhelm any protection device installed by any company. I've replaced a lot of wiring that contained no metal because lightening had passed through or circumvented protection devices and melted all the metal inside the insulation. Since an EMP device induces current flow it would do so on both sides of the protection device rendering the device invisible to the EMP source.

  16. #56
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    Whitis - I took some time to download and read through the document you referenced above. It makes some fascinating reading but it failed to include some important resources that are currently in place.

    1. Almost all power companies have mobile transformers that they can use while substations are being worked on either for upgrade, expansion or repair. Those mobile transformers could be used where outages occur in the 300 projected transformers referenced in the study. If a power company does not have enough mobile units they can call on other companies, even across country, to provide mobile units as well as manufacturers and equipment leasing companies that specialize in leasing long term power solutions.

    2. Their reference to 12 month lead times on manufacturing is under normal conditions. There are also hot spares programs in place that circumvent that process. If Company A has a planned expansion and will be installing a substation their order has already been placed with the manufacturer for the transformer(s). That transformer is already in process or may have been completed and be ready to ship. If Company B experiences a failure they can call the manufacturer and requisition Company A's transformer. It's just how the business works and Company B pays a premium to the manufacturer to be able to do that. If the transformer has been completed it is shipped to company B and Company A is first on the list to receive the next one manufactured. If it's in production phase then it's shipped when completed and Company A is still first on the list. If it's a massive outage that requires multiple transformers (as in a tornado or hurricane) then Company A is shoved down the list until Company B's needs are met. Maintenance takes precedence over upgrade and expansion. I've had to shut down projects before because I was in Company A's position and some outage in another company took my gear. I was always fortunate enough and we were big enough that I never had to invoke a hot spare for a project. We always had spares in place. But transformers, mainframe computers and servers all operate with a hot spares program.

    Finally, I had to read the study with a bit of a jaundiced eye. Metatech Corporation, which helped develop the study, suggested the installation of filters and transient suppressors to reduce the incidence of damage.

    "With respect to the entire grid, remedial measures to reduce GIC levels are needed and are cost-effective. The installation of supplemental transformer neutral ground resistors to reduce GIC flows is relatively inexpensive, has low engineering trade-offs, and can produce 60-70 percent reductions of GIC levels for storms of all sizes."

    It should be noted that Metatech was in the business of manufacturing EMI and transient suppressors through their commercial products division. They've since sold that business to Quell Corporation.

  17. #57
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    Quote Originally Posted by Allen Currie Author View Post
    Kyrat
    Even where I am at there isn't a light bulb within 10km, and I certainly wouldn't test there if I do at all. And the reason I would test is that I'm not positive it would work. I know how unreliable theories are. I doubt the explosion would take out more than one or two trees. Fear of forest fire would be one of the larger concerns. Every explosion creates at least a very small emp. The trick is to magnify it. Yes Rick, there are reasons not to particularly fear man made EMPs. But that very weakness can be turned into a strength.

    Allen
    If you test an EMP device in an area where there is not a light bulb within 10 KM you will still not know if it works!! Would you happen to be interested in an buying some swamp land in Florida? We are presently developing the technology to drain it, it just has not been done yet. Sale price will be computed based on the anticipated value of the swamp after the technology is developed. Get back to me on the deal the next trip you make to McDonalds for the free internet.

    If your device does work you are missing out on a fortune! The U.S. Army would pay big bucks for a portable device that would shut down a simple car engine as it approached a checkpoint after being told to hault. Presently we have to shut the engines down using .30 or .50 caliber machine gun bullets and a directed EMP device would save a lot of lives. I would have that thing patanted and in front of the DOD by sunset!


    I feel we should instate some prerequisites to pass before posting any EMP thread or response.

    First, if you are a believer you must own a horse and buggy in good usible condition and have at least a half acre of garden planted. A fully shielded off grid retreat home must be shown (this must be more than a shack in the woods). Their year of supplies must be accomplished as well as a year of emergency income.

    Second, you must understand what EMP is, how it is created and its actual capabilities at this point in history.

    Third, anyone claiming to have an EMP device must show proof it works, verified by the highest LEO of their district that they have knocked power out in a purposeful way and paid for the resulting damages. The test must include more than an AM radio exibiting static.
    Come to the dark side, we have pudding.

  18. #58
    Administrator Rick's Avatar
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    Would a prison sentence suffice as proof it worked?

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    And before I get lambasted....There is a huge difference between the amount of time it takes to manufacture an item and the amount of time the manufacturing process takes. If that doesn't make sense then consider that "six months to manufacture a transformer" implies that someone is working on it for six months. A six month manufacturing process means from the time the order is taken until the item is shipped. That does not mean that folks are working on it the entire six months. Huge difference.

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    Quote Originally Posted by Rick View Post
    I would humbly suggest that a nuclear device large enough to cripple the power grid would most likely leave us .... dead. In which case the grid is the least of my worries.
    False. Starfish prime caused emp damage 900 miles away. EMP levels were actually low (about 12% of the levels expected from an emp weapon) but if the burst had been more stragecally placed they would have been much higher. There were many nuclear tests conducted without killing large numbers of people. The circumstances which result in large numbers of deaths and those that generate widespread EMP are different.

    I would also like to see your reference on the six months required to build a transformer. Unless your reference is to extremely large sub-station transformers and even then I'd be shocked at that time frame.
    I didn't say 6 months, I said longer. And my statement was consistent with many of the major studies of effects of EMP on the grid. A source I linked to above(National Acadamy Press) said repairs could take 4-10 years. Also, if you can make 9 babies in 9 months it doesn't mean you can make 1 baby in 1 month. Here is a quote from the 197 page Mastech report:
    The failure of many large EHV transformers and the need to suddenly replace a large
    number of them has not been previously contemplated by the U.S. electric power
    industry. Under normal conditions, the purchase placement of a single EHV transformer
    order in the 300-400MVA class has normally been quoted as taking up to 15 months for
    manufacture and test. For larger sizes of transformers and transformers with special
    reactance or tap-changer requirements, several months may need to be added to the above
    mentioned figure, and the suitability of qualified manufacturers may be more limited.
    The rest is purely hypothetical except to say that the EMPs that have caused damage to date have not caused massive damage. They generally have affected a single or a few components that were already in disrepair, which resulted in a planned and controlled shut down of the grid.
    So far, we have been lucky in the game of EMP russian roulette. Our lucky streak is not likely to continue.

    The power grid is a relatively new development in human history. A century ago only a small portion of the US population had access to electricity. And the latter half of that history, as the grid got more complex, happened to coincide with a a relatively calm period in terms of geomagnetic storms. The 1989 storm completely destroyed just 1 big transformer but it caused 11 others to fail later. The 1982-07-13 storm missed us by about 6-7 hours (i.e. it affected other parts of the world more than here). When simulations shift the storm to occur on our side of the world, the stresses on the power grid are 3-6 times worse. A 4800nT/min storm (equivalent of what already happened in 1921 when we did not have much of a grid) at 50 degrees latitude produces stress on the grid that is 11 times higher than the 1989 storm. The 1989 storm did produce ground currents in Japan that if the happened in the US puts 42 500kV transformers (89% of capacity) in one category in the state of virgina alone) at risk of destruction (levels which have actually destroed transformers). A 2003 storm took out 14 400kV transformers in the tiny country of south africa at the tiny level of 100nT/min. Most of our transformer capacity is 30-40 years old.

    You actually have no practical references to claim that outages will be long term since none exist. And to say that power companies (or any company) has not learned from it's past mistakes is somewhat short sited. Not only are these types of events costly in terms of repair but also in terms of lost revenue. They also draw the ire of governing bodies as well as citizen groups that force changes. My experience has been it's much easier to make the correction up front than to have to deal with state commerce commissions or the FCC, which tend to go a bit overboard.
    If a major portion of the grid is damaged it will take a very long time to repair and I have provided multiple references for that. There won't be enough mobile spares to go around. The mastech report also notes that the eastern US grid uses many different designs of transformer making stocking spares more difficult. And there would not be enough transformers in the production pipeline to replace the large numbers of units predicted to be destroyed in a severe EMP event.

    You give the corporations too much credit. The S&L crisis, the banking collapse, and the collapse of the auto industry are a few examples of how corporations ignored very foreseable and inevitible risks and then depended on government bailouts. It wasn't in BP's financial interest to disregard the safegards which lead to the deepwater horizon blowout, either.

    An outage the scale that you are talking about is never a single cause event. It is, rather, a series of events, often involving human error, that cascade into a large scale event. Here is a link to a perfect example. If you scan down the page you'll see the time line. Look at all the events that occurred that tied what should have been isolated incidents into a large scale blackout.

    http://en.wikipedia.org/wiki/Northea...ence_of_events
    In the case of EMP, many causes can have a single root cause. If our systems fall apart due to isolated independent failures, a coordinated series of failures is much worse.

    Incidentally, a post mortem is generally conducted on any large scale event in order to determine the cause(s). That post mortem will also include corrections to preclude future events from occurring.
    The major reports on EMP type events show that the grid is at risk.

    Finally, your reference to surge suppressors, even following single point grounding in accordance with federal electrical standards offer little protection against anything other than minor voltage fluctuations, which is what they were designed for. Lightening or a large emp event of any source can and will overwhelm any protection device installed by any company. I've replaced a lot of wiring that contained no metal because lightening had passed through or circumvented protection devices and melted all the metal inside the insulation. Since an EMP device induces current flow it would do so on both sides of the protection device rendering the device invisible to the EMP source.
    Serious lightning grade surge supression can significantly reduce the risk of damage. An intense direct strike will overwelm most lightning supression. But grounding done merely in accordance weak standards would be laughable in terms of serious lightning protection. Most damage is caused by less severe lightning events.
    There are systems that survive frequent direct strikes. Arrestors with 300kA rating (extreme positive llightning) are made. Here is an example of a ham radio station that survives monthly direct hits: http://www.w8ji.com/station_ground.htm
    Lightning or EMP spikes can be induced in wiring inside the building which is one of the reasons to have supressors at the equipment as well as at the point of entry.

    Mastech report:
    http://www.fas.org/irp/eprint/geomag.pdf

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