It's important to realize that such weapons will be relatively small. This reason for this is that when a bomb increases in size by a factor of ten, its destructiveness is only roughly doubled. Militaries employ large numbers of smaller nukes rather than just a few large ones; smaller bombs and warheads are more easily delivered and give more bang for the buck.
Terrorists would use small bombs for much the same reason. Small nukes would do a lot of damage while being easy to conceal and deliver. While the anti-nuclear activists of the 1980s liked to describe the devastation the largest possible nuclear bomb would cause, in reality much smaller bombs would be used in almost any attack you might face in the future.
You can survive quite close to "ground zero" if a small nuclear device explodes. The population in Nagasaki was unprepared for any sort of attack; but there were survivors who chanced to be in bomb shelters when the nuclear explosion occurred. Some of these people were just one third of a mile from ground zero when the bomb exploded. A good shelter can be the ticket to surviving a nuclear attack. Since the Nagasaki bomb was not all that different from those that might be encountered in a limited war or terrorist operation, you could survive a similar blast even if you're just a mile from ground zero.
Of course the farther you are from ground zero, the better off you'll be. For this reason, one good survival strategy is to be away from areas that are apt to attract attacks. Washington, DC, New York City, or other big cities may be glamorous, but if the street crime isn't enough to turn you away the nuclear threat probably should be. Ditto for those living close to large harbors, military complexes, or other possible targets. Moving away from such areas will probably keep you safe from nuclear attack for the rest of your life.
Regardless of the size or source of a nuclear explosion, the energy released will be in a several forms including visible light (at its peak, four times as bright as the sun), thermal (heat) rays, and ionizing radiation in the form of gamma rays, neutrons, Alpha particles, and Beta particles (with fallout arriving some time later if it has been created by the explosion).
The release of energy during the explosion super heats the air around it until it is hotter than the face of the sun. This air expands violently making a blast wave that races from ground zero (the center of the explosion) at up to 4,000 miles per hour (fortunately this speed drops off quickly as the distance from ground zero increases). The air ahead of the blast wave is compressed; it bends light and appears slightly luminous and will appear as a sheet of glass moving out from the center of the explosion. The blast sounds -as an unknown observer once said "like the gates of Hell clanging shut."
As the blast wave storms away from ground zero, the fireball that created it rises so quickly that it creates a vacuum under it. The vacuum pulls air back toward ground zero so that the blast wave is followed by a counter wave sucked back toward the area of the explosion to fill the vacuum. Both the blast wave and the counter suction wave are destructive.
All in all, you won't have trouble knowing a nuclear explosion has occurred especially since its fireball will be four times as bright as the sun. Now what steps will be most apt to save you?
First: Do not ever, ever look toward a nuclear flash. The intense light will burn into your retina to create blind spots. This damage will make spots similar to those you see when you look at a bright light; only these won't go away they'll last the rest of your life.
If you don't look directly at the flash, the intense light reflected from light colored surfaces may still dazzle your eyes. If you're driving or doing anything that absolutely requires that you see, stop immediately; this will keep you from having to "drive by braille" when the bright light goes away and you're left in "snow blindness" for a short time. Although such blindness will only be temporary, tooling down the road at 55 MPH or running a buzz saw while you're "in the dark" isn't too good of a survival strategy.
To avoid complete "snow blindness" when it is necessary to see to find your way to a safe place, you should close one eye. This will allow you to get off a road or into shelter so that one eye can "see" with the eye you closed after the fireball is gone. If at all possible, however, you should cover both eyes at the first sign of the flash to avoid any chance of damage to them.
There are two immediate dangers you'll have to face after the initial flash of a near by nuclear weapon. The first is the pulse of radiation following the light and the second is the blast wave traveling behind it.
You won't have much time to look for safety. Only a few seconds. Fortunately, of the whole spectrum of radiation given off by nuclear explosion, the visible light is given off first, thereby giving you a slight lag time before the more dangerous thermal, gamma, and neutron radiation reach peak levels and start moving out from the blast.
This short grace period gives you time to "duck and cover" as they called it during the 1950's. Such quick action can be very effective in minimizing both radiation exposure as well as keeping you from getting burns from the thermal pulse. Far from being something ineffective (as some peace activists have suggested), the duck and cover strategy can be a real life saver.
What should be ducked behind?
It should be something heavy so that a blast wave can't move it around and so that it can shield you from flying debris. But even if almost nothing is available, just hitting the dirt and covering your exposed skin with clothing can still help to minimize skin burns and puncture injuries.
How long should you stay down?
You should not jump right back up after the flash subsides since a blast wave may be thundering toward you. If you're dangerously close to the blast, the wave may reach you in just 2 to 15 seconds; if the blast wave is going to be dangerous, it should have passed through your area after two minutes. So, after your duck and cover maneuver, you "one thousand one, one thousand two, one-thousand three..." it until you've counted off two minutes. If there are multiple explosions, then you start counting again with each new flash (which will be visible even with your eyes closed unless you're in a windowless room).
Here's the drill: Bright flash? Dive for cover. Your response needs to be automatic. Yelling, "Hit the deck" to those around you may save them as well since we've all seen enough war movies to know what the order means and many people react reflexively to this command, especially if there's a bright flash. You may save several lives by yelling this.
Stay down for two minutes. If the blast wave is going to be dangerous, it will pass through your area within this time. (Of course if there are multiple explosions, you'll have to wait until two minutes after the last flash.)
The blast wave will create several real dangers. Indoors, glass is the worst worry even some distance from the blast. Closer to ground zero, other flying debris like plaster or chunks of wood become equally dangerous and the blast itself can send YOU flying if you don't have the sense to get down. Consequently, you should dive for cover behind something that will offer protection both from the thermal radiation as well as blast-hurled missiles.
If you're out in the open when a flash alerts you to a nuclear attack, all isn't lost. Diving into a ditch or other depression is the best strategy, but even if these aren't available, covering your head and lying with your feet pointed toward the blast can improve your chances considerably; such a position will help to keep you from being blown about and your shoes give good protection to your feet (which can withstand more abuse than your head to start out with).
After the "two minute wait" for the blast wave to pass by, you should get up and head for permanent cover. And that brings us to the most long lived effect of many nuclear weapons: radioactive fallout.
The "fallout" from a dirty bomb won't technically be radioactive fallout. Instead it will be the scattered remains of the original radioactive materials used to make the bomb. The good news is that there won't be much of it compared to a real nuclear weapon; the bad news is that it will have a half live very much longer than that of a conventional nuclear bomb. Instead of being dangerous for weeks, the radioactivity from a dirty weapon will be of concern for years and most likely centuries without proper cleanup of the area.
A dirty bomb will be easy to spot. The blast wave, if any, will be very limited and will extend only hundreds of yards from the explosion. There'll be very limited damage like that produced by a car bomb--but with radioactivity in the dust and rubble.
You might have to do the detection of radioactive particles on your own; following the World Trade Tower bombing, there was no sign of any officials using radiation meters. Had a dirty bomb been used, it's likely that the contamination would have been spread over a huge area, tracked to area hospitals, fire stations, and police stations with the activities of rescue crews and victims before anyone detected its presence.
The lesson to be learned here is that if you know or suspect that a dirty bomb has been used, there may not be any official confirmation of the fact for hours or even days. For this reason you would ideally have some radiation detection equipment of your own, to do the job the officials may fail to do. Lacking that, you need to be very, very cautious if an explosion seems suspicious.
If you suspect or learn that a dirty bomb has been employed, then leaving the area would be the first option to consider. But remember that becoming a refugee puts you at the mercy of strangers. Have a "bugout" bag of supplies and necessities ready to go (a wise precaution for a lot of other catastrophes as well).
When word gets out that there are dangerous levels of nuclear materials in an area, there will be a panic with large numbers of frantic people clogging city streets. In such a case, you're better off sitting tight until the congestion is cleared or goes into gridlock.
If a real nuclear weapon has been detonated near the ground, there will soon be fallout raining into your area. In such a case you're probably better off hunkering down and waiting until the levels of radiation outside have dropped to safer levels. This is especially true if you have a large stock of supplies and perhaps even a fallout shelter (even if it's only improvised in a corner of your basement); in such a case you'd be better off ignoring official orders to evacuate and going it alone. Such a tactic has the added benefit of permitting you to protect your home from looters who may try to take advantage of the confusion.
What is fallout? Radioactive fallout is created when the suction wave of the blast carries matter upward with the vacuum created by the nuclear fireball as it rises. If the explosion is close to the ground, the matter sucked from the surface of the earth moves into the fireball and is incinerated by the intense heat. (This dust is the "stem" that gives ground bursts their mushroom shape.)
As the debris is pulled up into the nuclear explosion, it's exposed to the radiation produced by the chain reaction; this exposure induces radioactivity in the debris. As this molten, now radioactive debris continues upward, it cools off and solidifies into small particles which gradually fall back to earth. These particles are radioactive fallout.
Fallout travels upward a long way; it takes quite a while for it to fall back down. Even close to ground zero, it will take at least 15 minutes for large sand to pea sized pieces of fallout to return to the earth. Smaller pieces, falling farther downwind from ground zero, will take longer with the very smallest of particles remaining airborne for days, weeks, months, or even years as they are blown farther and farther by high altitude winds.
This lag time that it takes for the fallout to arrive on the ground is a big plus which many are unaware of. Because of the time needed before fallout can reach the ground, areas down range which will eventually receive dangerous levels of fallout will remain free of radioactive particles for up to several hours following a nuclear blast. This gives you time to make last minute preparations or even travel to a safer location if you're caught away from home during the attack or even pick up the children from school if they are close by. You'll have at least 15 20 minutes and more likely an hour or more.
Because large particles of fallout will arrive before the smaller ones, you'll not have trouble spotting fallout unless you're so far down wind that only small particles will be arriving many hours or even days later. Large fallout will arrive in a variety of forms and color (due to its make up and depending on the material that was at ground zero). White, gray, or even black ash or popcorn like particles could be encountered.
Regardless of its form, it will be falling from the air and will appear unlike any natural phenomena. You'll be able to recognize it for what it is. When the fallout starts to arrive, you must get out of it as soon as possible (and ideally -would be out of the open well before fallout started to arrive).
If you are forced to be in the open, keep radioactive fallout off your skin and clothing by brushing it off. Cover your head and use a wet handkerchief over your face to keep from inhaling the dust if you don't have any other sort of dust mask available. Remember: any time spent in the fallout will greatly lower your chances for surviving. Get into a shelter of some sort as soon as you can.
During the critical time before fallout arrives, it's important that you don't get side tracked since you don't know how much time you really have. Do first things first. Let tasks slide that aren't essential. Remember, too, that communications will be disrupted, buildings may be destroyed, many people will be panicked and/or injured.
Be prepared to look out only for yourself and your family; trying to "save" everyone will only result in everyone's loss. While this seems harsh, those who haven't taken a few minutes to learn about how to survive a nuclear attack are going to be so ill prepared that they'll soon perish in any area where lethal amounts of fallout to come into the area they're in unless they are extraordinarily lucky. If you really care about these people, you should try to tell them how to survive NOW, well before a nuclear attack; last minute teaching won't take place when the bombs have exploded and the fallout is ready to rain down. Once the attack has taken place, save yourself and your family and let those who have gambled with their future by not preparing to survive pay the piper.
During such a time of panic and confusion, you'll need to be careful you don't get sucked into unwise decisions or suggestions from others who don't have any real idea of what is going on. This will include many "authorities" who are completely ignorant of what a nuclear attack would be like. School officials, your boss, policemen, national guard troops, etc., may all be giving orders and instructions which if followed could result in your death or the death of your loved ones. Ignore the chaos and go about your business of surviving as quickly as possible.
If you're away from home and can't get back to your family shelter, don't seek shelter someplace which will gradually become packed with people. This includes all US "public fallout shelters" which, as most readers know, are currently only signs on public buildings (the exception to this rule are shelters created for Congress which have been and continue to be fully stocked). To put it bluntly, public shelters are potential death traps.
If you travel a lot, or work some distance from your home, then a bugout bag of essentials would greatly improve your chances as well. This bag could be kept in a closet or locker at your place of work or in the trunk of your car. It could get you through the arrival of the fallout and then you could travel back to your home on foot to join your family weeks later.
If you prepare ahead of time, you can minimize potential thermal pulse and blast damage to your home. One important point is to choose a home with a light colored roof and exterior paint (both are especially important on wood frame houses); light colors reflect both light and heat making your home more fire resistant to the thermal pulse of a nuclear weapon. Avoid a weathered wood exterior on your home and don't paint it a dark color. Brick or stone facings are first choice both for the added shielding they give from radiation as well as their resistance to thermal damage.
Terracing around your home can also add a lot of shielding to a basement -- creating a potential make-do shelter in the process. Such work can be very attractive and can even improve the value of your home if you sell it.
Some trees, shrubs, and grass are more fire resistant than others and should be considered for planting around your house. Evergreens tend to be more flammable than deciduous trees and are best avoided in areas very close to targets (where a thermal pulse could set the trees on fire).
Your lawn shouldn't turn brown in the fall (Bermuda grass is especially bad about this). And be sure to keep dead bushes, piles of leaves, etc., well away from your house so that they can't start a fire following a thermal pulse. For the same reason, don't stack firewood next your home and keep the garage free of stacks of old newspapers and cardboard boxes.
Since a nuclear blast can turn windows into jagged daggers, it's wise to take some steps to minimize this danger. One way to help keep chunks of glass in the window is to place an "X" of tape across each pane of glass. Cloth tape is best for this, but multiple layers of scotch tape, clear packing tape, or contact "paper" (which is actually plastic) over glass panes will also improve things if you're worried about how your windows look to the neighbors. Best bet is to replace glass in bedrooms or other areas where you may not be able to react quickly to an oncoming blast with plastic. Most hardware stores stock clear plastic that can be used in windows.
White reflects light; that means white drapes, curtains, or shades are more ideal than darker colored window coverings when it comes to reflecting a nuclear thermal pulse. These light colors will reflect much of the light and thermal pulse back out your windows and might even save you from having a fire indoors.
After the nuclear blasts have occurred, you should take a few steps to protect you home from further damage while you're in your shelter. If your area may have freezing weather while you're holed up, it's a good idea to drain the water out of your home's pipes to keep them from rupturing and damaging the inside of your house.
Patching up any light damage done to your house by a nuclear blast is also a good idea if it can be done quickly before fallout enters your area. Windows and doors can be sealed with large strips of plastic or duct tape to minimize the entrance of fallout dust. Shutters or large sheets of plywood might be used to close up windows which might be easily used for entrance by looters who don't have the good sense to get out of the fallout once it starts to arrive. Doors and windows can even be nailed shut but be sure you leave several ways for you to escape from your home quickly should there be a house fire or similar disaster.
The aftermath of a nuclear attack would be no picnic. But, with some advanced preparations and common sense tactics like "duck and cover", you could survive and live to help rebuild your neighborhood and perhaps even help create a new nation.
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