Protecting Yourself from EMP
EMP. The letters spell burnt out computers and other electrical systems and perhaps even a return to the dark ages if it were to mark the beginning of a nuclear war. But it doesn’t need to be that way. Once you understand EMP, you can take a few simple precautions to protect yourself and equipment from it. In fact, you can enjoy much of the “high tech” life style you’ve come accustomed to even after the use of a nuclear device has been used by terrorists—or there is an all-out WWIII.
EMP (Electro-Magnetic Pulse), also sometimes known as “NEMP” (Nuclear Electromagnetic Pulse), was kept secret from the public for a long time and was first discovered more or less by accident when US Military tests of nuclear weapons started knocking out phone banks and other equipment miles from ground zero.
EMP is no longer “top secret” but information about it is still a little sketchy and hard to come by. Adding to the problems is the fact that its effects are hard to predict; even electronics designers have to test their equipment in powerful EMP simulators before they can be sure it is really capable of with standing the effect.
EMP occurs with all nuclear explosions. With smaller explosions the effects are less pronounced. Nuclear bursts close to the ground are dampened by the earth so that EMP effects are more or less confined to the region of the blast and heat wave. But EMP becomes more pronounced and wide spread as the size and altitude of a nuclear blast is increased since the ground; of these two, altitude is the quickest way to produce greater EMP effects. As a nuclear device is exploded higher up, the earth soaks up fewer of the free electrons produced before they can travel some distance.
The most “enhanced” EMP effects would occur if a nuclear weapon were exploded in space, outside the Earth’s atmosphere. In such a case, the gamma radiation released during the flash cycle of the weapon would react with the upper layer of the earth’s atmosphere and strip electrons free from the air molecules, producing electromagnetic radiation similar to broad-band radio waves (10 kHz-100 MHz) in the process. These electrons would follow the earth’s magnetic field and quickly circle toward the ground where they would be finally dampened. (To add to the confusion, we now have two more EMP terms:
“Surface EMP” or “SEMP” which refers to ground bursts with limited-range effects and “High-altitude EMP” or “HEMP” which is the term used for a nuclear detonation creating large amounts of EMP.)
Tactically, a space-based nuclear attack has a lot going for it; the magnetic field of the earth tends to spread out EMP so much that just one 20-MT bomb exploded at an altitude of 200 miles could—in theory—blanket the continental US with the effects of EMP. It’s believed that the electrical surge of the EMP from such an explosion would be strong enough to knock out much of the civilian electrical equipment over the whole country. Certainly this is a lot of “bang for the buck” and it would be foolish to think that a nuclear attack would be launched without taking advantage of the confusion a high-altitude explosion could create. Ditto with its use by terrorists should the technology to get such payloads into space become readily available to smaller countries and groups.
But there’s no need for you to go back to the stone age if a nuclear war occurs. It is possible to avoid much of the EMP damage that could be done to electrical equipment—including the computer that brought this article to you—with just a few simple precautions.
First of all, it’s necessary to get rid of a few erroneous facts, however.
One mistaken idea is that EMP is like a powerful bolt of lightning. While the two are alike in their end results—burning out electrical equipment with intense electronic surges—EMP is actually more akin to a super-powerful radio wave. Thus, strategies based on using lightning arrestors or lightning-rod grounding techniques are destined to failure in protecting equipment from EMP.
Another false concept is that EMP “out of the blue” will fry your brain and/or body the way lightning strikes do. In the levels created by a nuclear weapon, it would not pose a health hazard to plants, animals, or man PROVIDED it isn’t concentrated.
EMP can be concentrated. That could happen if it were “pulled in” by a stretch of metal. If this happened, EMP would be dangerous to living things. It could become concentrated by metal girders, large stretches of wiring (including telephone lines), long antennas, or similar set ups. So—if a nuclear war were in the offing—you’d do well to avoid being very close to such concentrations. (A safe distance for nuclear-generated EMP would be at least 8 feet from such stretches of metal.)
This concentration of EMP by metal wiring is one reason that most electrical equipment and telephones would be destroyed by the electrical surge. It isn’t that the equipment itself is really all that sensitive, but that the surge would be so concentrated that nothing working on low levels of electricity would survive.
Protecting electrical equipment is simple if it can be unplugged from AC outlets, phone systems, or long antennas. But that assumes that you won’t be using it when the EMP strikes. That isn’t all that practical and—if a nuclear war were drawn out or an attack occurred in waves spread over hours or days— you’d have to either risk damage to equipment or do without it until things had settled down for sure.
One simple solution is to use battery-operated equipment which has cords or antennas of only 30 inches or less in length. This short stretch of metal puts the device within the troughs of the nuclear-generated EMP wave and will keep the equipment from getting a damaging concentration of electrons. Provided the equipment isn’t operated close to some other metal object (i.e., within 8 feet of a metal girder, telephone line, etc.), it should survive without any other precautions being taken with it.
If you don’t want to buy a wealth of batteries for every appliance you own or use a radio set up with longer than 30-inch antenna, then you’ll need to FULL ARTICLE HERE