Seeking EMP knowledge

Discussion in 'General Preparedness Discussion' started by Practical Madman, Jun 14, 2009.

  1. Practical Madman

    Practical Madman Member

    Does anyone have knowledge of EMP and how to protect from it? My question is does good old dirt give protection? I am digging a bunker, with wood walls and roof. Will put Mylar blankets on the roof, cover with plastic and then 18" of dirt. Bushes planted around it and grass on top will camo it. Will this protect electronic equipment inside from EMP? Are solar panels subject to EMP waves?
  2. doc66

    doc66 Well-Known Member

    Well, the short answer is simple; there is no real knowledge of EMP.

    Many theories abound, but none of them can tell you the real truth. The most recent, and the one I like, is that EMP is like water--depending on where you are in relation to the EMP pluse is what effect it will have on you and your crap. The EMP will roll around hills and those items directly behind the hill will not be effected. Things inside buildings, depending on where they are in the building, what the building is made of and how close it is to the source of the blast may or may not be effected. Any circuits in direct contact with the EMP wave may be effected. It depends on if they are open or closed circuits, grounded or hardened and how far away from the EMP you are.

    There is no good answer.

    Your set up sound reasonable, but I'd have the solar panels taken down should you get early warning and spares just in case. The biggest problem with ANY bunker is the air cleansing and circulation. A friend of mine and others did a 72 hour test of a bunker and found that even though the air system was supposedly set up for twelve people (they had eight) it was not enough to realistically deal with the amount of CO2 being put out. He said that they went just over 48 hours and by the end of that time they were down to shorts and the humidity was so high that water was literally dripping off the ceiling.

    Whatever you plan for, plan for at least twice as many people as advertised and have backups for everything.

  3. Canadian

    Canadian Well-Known Member

    Wrap your ipod in foil? I don't know much about EMP but enough dirt seems to stop anything. Even a nuke.
  4. SurvivalNut

    SurvivalNut Retired Army

    Good question.

    Here is an article posted on our brother Aussie site.

    AusSurvivalist - EMP Protection

    I keep some redundant items (radios, commo, batteries, small solar chargers, my radiation monitoring gear) packed in Faraday boxes.

    As for solar panels, they are relatively new and I would not trust any single answer without reserve.

    I like the answer to stow them inside or to have a smaller back up set inside.

    My totally uneducated guess is that solar panels would be very susceptible unprotected.
  5. Herbalpagan

    Herbalpagan Well-Known Member

    You can put small thing you wish to save from EMP in an old (unplugged) microwave, as it's a Faraday cage. I hear a lot of people saying they will just store their cell phone in one, but honestly, who ya gonna call if the cell sats are fried? I'd put a small radio in it. I think the shelter has to be surrounded by grounded metal in order to be protected.
    I did a google search on EMP, EMP bombs and general info. I know that electronics made for the military has to be hardened, but not a lot of testing has been done with an actual nuke/EMP such as discribed in recent books. The last tests on that were done in the 60's when electronics were not so sensitive. Though there are several EMP "machines" now for testing, it still doesn't simulate the situation you are looking for.
  6. NaeKid

    NaeKid YourAdministrator, eh?

    You can visit's EMP information area for more detailed information regarding EMP

    From what I have been able to learn, an EMP (ElectroMagneticPulse) will travel via power lines / TV-Cable / TelephoneLines and anything that is within a certain distance of that cable, or, attached to that cable will be fried.

    Your vehicle is safe - unless you are driving an electric car and it is plugged in for charging.

    A solar panel is safe, unless it is attached to your house and there is power coming into the house as well and you are "pushing" power back into the power-grid. A solar panel attached to your camping trailer that is parked away from any power lines should be safe.
  7. The_Blob

    The_Blob performing monkey

    here's a BUNCH of stuff... :rolleyes: :D ;)

    from: Utah Shelter Systems - Because Survival Is The Highest Priority

    Solar panels may be used to recharge the batteries, but when not in use they should be stored inside the shelter for maximum protection from blast and EMP. They should be placed outside only after all danger of blast &/or EMP has passed. They will be adversely affected by the EMP. If in a remote area, consider putting out a ‘sacrificial’ panel and purchasing extra solar panels for later. Store these panels wrapped in aluminum foil, for 'EMP' protection, and keep them inside your shelter until use.

    Weapons Effects

    EMP Effect
    Most experts agree that a full scale nuclear attack would be initiated by a high altitude (approximately 200 miles high) nuclear explosion, and that it would most probably be deployed from a satellite. A nuclear bomb detonated at that altitude will not damage living tissue, will not cause significant radiation fallout and is not a health threat to the population. The purpose of this explosion is to damage critical electrical circuitry in our retaliatory defense weapons and our military communications capabilities. This is accomplished by means of the electro magnetic pulse (EMP) associated with the explosion. One such explosion could affect an area of a thousand miles in diameter.

    Terrorist nations can deploy EMP weapons from surface to air missiles detonated from a ship in our costal waters. Iran's, Shahab-3 ballistic missile, if armed with a nuclear weapon, would have this capability. North Korea, an ally of Iran, boasts that they already have nuclear weapons with ballistic missiles capable of reaching these heights.

    Collectors, such as long runs of cable, house wiring, conduit, large antennas, overhead power and telephone lines, railroad tracks, etc., gather this energy in the form of a strong current and voltage surge. All solid state electronics is vulnerable to this energy surge. The equipment does not have to be attached directly to the collector in order to be damaged. It's possible for a collector to gather in the order of a joule of energy from a one megaton, high altitude explosion. The fact that a small fraction of a joule can cause permanent damage to electronic devices, shows that the EMP threat is a serious one. The damage to equipment could include automobile ignition systems, telephone and radio communications, airline communications, navigational aids, & computers. The power grid throughout the United States would most probably fail. It is estimated that about 95% of our radio stations would immediately loose transmission in an EMP attack.

    If a power drop is detected, care should be taken to test telephones, radio stations, and other equipment for loss of function. Many radio stations have alternate power sources, but only about 5% of our radio stations have been hardened against the EMP. If, after checking a battery powered radio, you find that most of the radio stations are not functioning, you should take shelter immediately.

    Immediately after the initial EMP explosion, SLBM's and ICBM's would probably be launched against targets in the United States. An ICBM from Russia would reach the center of the continental United States in about 25 minutes. A missile from a submarine could reach us in 8 minutes. However, we are not currently seeing Russian nuclear missile submarines in our coastal waters. The 25 minutes which the power failure alarm will give you could mean the difference between life and death.

    If you are asleep, a simple power-drop alarm would awaken you when the power fails. This alarm should be constructed by a certified electrician. Our electrician used a motorcycle horn, a 12 volt battery, a relay switch, and a flasher. The negative line from the battery was connected to the 12 V DC horn. When the 110 V AC currant fails, the relay closes the circuit, which activates the horn. He added a switch to the positive line from the battery to the horn so the horn can be turned off after activation.

    If the fireball of the weapon touches the ground, the blast is defined as a `ground burst'. In a ground burst, rock, soil, and other material in the area is vaporized and taken into the cloud. This debris is then uniformly fused with fission products and radioactive residues and becomes radioactive itself. It then falls to the ground as `radioactive fallout'. If the fire ball from the explosion does not reach the ground, the blast is said to be an `air burst'. Radiation (except for initial radiation) does not become a factor in an air burst.

    Gamma rays from the fallout can easily be attenuated by incorporating a 90 degree turn in the small diameter entrance. Entrances should not exceed 48 inches in diameter and the total length of the vertical and horizontal run should be no less than 25 feet. Approximately 90% of the gamma radiation is directed into the ground from the vertical portion of the entrance. The other 10% is almost entirely attenuated by the horizontal portion of the entrance. We recommend that the horizontal portion of the entrance be about 10 feet long and that it penetrate the shelter body on the side or on the end plate.

    The threat of exposure to initial nuclear radiation is confined to a radius of about one and one half miles from ground zero and would prove fatal to any unsheltered individuals. However, in hardened blast and radiation shelters, such as those that are being built by Utah Shelter Systems, people could survive all nuclear weapons effects, including initial radiation, within three quarter mile of ground zero. Shelters which may be within the initial radiation zone, must have at least 8 ft. of dirt cover and the entrances must be configured with the proper shielding and geometry.

    Gamma radiation is a great health problem for a two week period. Everyone should stay sheltered in a good fallout shelter for two full weeks. If blast is not a consideration, 4 feet of earth cover is sufficient to shield from gamma radiation. However, the entrances must still each have the 25 feet with both horizontal and vertical runs.

    Alpha and Beta radiation can be stopped by a few layers of paper. However , internal to the body, they are a great health hazard. We must be careful to wash the lids of dust before opening canned food, and wash and peel all exposed fruits and vegetables. Water purification, food preparation, and post war survival will be discussed in another section of this web site.

    Blast Effect
    In the detonation of a one megaton size weapon (which is roughly equivalent to 1 million tons of TNT), the fireball grows to 440 feet in just a fraction of a second. In 10 seconds, the fireball is over a mile wide. At the same time the fireball is forming and growing, a high-pressure wave develops and moves outward in all directions. This wave of air causes a huge increase in air pressure. At one quarter mile from the crater edge, the overpressures are about 200 psi. It is not expected that nuclear weapons with a greater yield than one megaton would be used against the civilian population. We are, therefore, limiting our discussion of blast effects to that yield.

    At approximately 4 miles from the epicenter, the winds are 165 mph and the overpressure is approx. 5 psi. Most homes would be destroyed, but it is possible to survive the blast in a basement shelter at that distance. The radiation shielding from the home, however, may have been destroyed in the blast. At 6 and 7 miles from the epicenter, there would be moderate damage to residences and the likelihood of surviving in a basement is greater.

    People housed in hardened blast and radiation shelters, such as are built by Utah Shelter Systems, would be expected to survive all NBC weapons effects at ground zero from an air burst (50 psi), and at one quarter mile from the crater edge from a one megaton yield ground burst. At that proximity, an 8 ft. diameter shelter must have at least 8 feet of dirt cover. A 10 foot diameter shelter must have at least 10 feet of dirt cover over head. Each person must have approximately 10 square feet of shelter space for short term survival (up to 2 weeks). Double this space requirement if the shelter is to be used as a permanent residence.

    Thermal Effect
    Within less than a millionth of a second of the detonation, large amounts of energy in the form of invisible x-rays are absorbed within just a few feet of the atmosphere. This leads to the formation of an extremely hot and luminous mass called the fireball. If we were standing 50 miles away, this fireball would appear to us to be many more times as brilliant as the noon day sun.

    You should never look directly at the fireball of a nuclear explosion. Because of the focusing action of the lens of the eye, especially at night when our pupils are open, thermal radiation can cause temporary and even permanent blindness.

    The thermal pulse travels at the speed of light and can last for a fraction of a second, up to several seconds. It also generally travels in straight lines, as does light. If there is no warning, you should drop and cover immediately. If you do have warning, you should take cover behind a large structure, or go to a basement or culvert. If unprotected you would receive third degree burns at 6 to 8 miles from the blast; second degree burns at a distance of 8 to 10 miles; and first degree burns at 10 to 12 miles from the blast. Burns would greatly complicate an otherwise survivable situation.

    an 11 page document by Dr. Lowell Wood about EMP

    the 31 page excerpt from the House Committee on Armed Services

  8. SurvivalNut

    SurvivalNut Retired Army

    All good information here.

    One note, some writings suggest grounding ATTRACTS rather than diffuse EMP.

    A farraday box is not a ground, unless you go overboard and wire it. Don't.

    Posted for consideration.
  9. Ponce

    Ponce Well-Known Member

    Do a search in "Popular Mechanics", they even show you how to build a bomb for under $1,000........hummmmmmmmmmm.
  10. The_Blob

    The_Blob performing monkey

    good luck getting the fissile material, ace ;)
  11. JohnB

    JohnB New Member

    This is pretty much in line with what I've been able to research. The EMP will pretty much be attracted to the power grid and anything attached to or plugged into it.

    Practical Madman: your bunker should be OK as long as you are not plugged into the local power supply.
  12. NaeKid

    NaeKid YourAdministrator, eh?

    I am in the process of testing power-supply systems right now. I am hoping that within a year I will be able to flip-over from testing to a production-type living. What I hope to do is either build a new house based on 12-volt RV technology or convert an existing house to 12-volt primary if I can't find the right section of land to purchase (hoping to do so prior to this winter).

    With the market the way it is - my plans all hinge on the selling of my current house.
  13. grizz3000

    grizz3000 New Member

    A vehicle with Electronic Fuel Injection (EFI) WILL get fried unless you have the frame grounded (i.e. clamped to a grounding rod in the garage or dragging a chain while moving/parked). Most cars prior to ~1975 are not EFI.

    Solar panels will most likely get fried since they are essentially one big diode. The batt controller and inverter will mostly get fried too. Don't forget, anything with power connected to it will get fried (i.e. a car connected to a battery, solar panels providing power to batterys, etc)

    I think everyone should do research before posting/telling someone information.
  14. Turtle

    Turtle Well-Known Member

    The Pentagon did a study about the effects of a large-scale EMP burst on the U.S. about ten years ago. It cenetered on the fact that a low-yield nuke, detonated at the proper elevation, could use the Earth's atmosphere to conduct the EMP over 66% - 75% of the world's surface.

    Reason we never heard about it? The finding were set to be released on 11 September, 2001.:rolleyes:

    I'm certain that if you invoke the FOIA, you could get a redacted copy of the findings.
  15. Skeeter

    Skeeter Well-Known Member

    Reason we never heard about it? The finding were set to be released on 11 September, 2001.

  16. Turtle

    Turtle Well-Known Member

    Several. But if you pick up a copy of William Forstchen's book, "One Second After" (which is a fine book, by the way), there is a foreword by Newt Gingrich, who I believe was on the investigatory committee, and an afterword by the Navy officer who was in charge of the investigation.
  17. HappyPreppers

    HappyPreppers New Member

    EMP effects indeed are like WATER! That's a good analogy.:)

    -- Happy Preppers
    We believe the happiest people on earth will be those who've prepared when the unthinkable happens.
  18. Caribou

    Caribou Time Traveler

    I think your design would work well enough for its stated purpose of EMP protection. The Mylar will help quite a bit.

    Personally I would put at least four feet of dirt over myself for added radiation protection. Going as far as you are going this added protection seems reasonable to me. If I lived close enough to a target to need more than four feet of dirt over my head I'd move, but that is just me.

    Test your system. Any area where you lose signal on your cell phone should be fine for your electronics.

    Doors and ventilation may well be weaknesses. Wire screens over ventilation should help with bugs and EMP. Any wires or metal pipes that run outside may well act as an antenna and draw the EMP pulse into your bunker.
  19. labotomi

    labotomi Well-Known Member

    That's not a good test. The wavelengths resulting from an EMP are not the same as those used by cellphones.

    It's similar to how different frequencies of cordless phones affect their range. Some will travel a very long way but will be blocked by a few walls. Some can perpetrate those few walls but not have nearly the same range as the others.
  20. northstarprepper

    northstarprepper Preparing for the End Times

    I was thinking of putting two one inch diameter iron grounding rods on each side of my driveway. Then I would keep each vehicle parked there connected with heavy-duty jumper cables attached to the frame. Do those of you with more knowledge of auto electronics than myself think that would keep the electronics safe in my cars? I am unsure what else to do other than find someone with an all metal storage building that I could store a vehicle in for such an emergency. Any other ideas?