Before You Start Worrying About Surviving In The Post-Nuclear Holocaust World, There Are A Few More Immediate Dangers To Get Through

Surviving a nuclear attack means preparing in advance and protecting yourself from radioactive fallout for weeks after the weapons go off – but if you’re anywhere near the actual explosions, the actions you take in the first few seconds are going to decide whether anything else even matters. A nuclear weapon has great destructive power and can kill, injure and destroy over a huge area. If you’re inside its destructive radius, and you don’t know how to react, your chances of survival will fall dramatically.

Unlike a conventional explosion, a nuke doesn’t just create a blast wave that can either cause damage directly or throw projectiles out as shrapnel. It does create a blast wave – a massive one – but there are other effects to worry about as well. The first effect is the thermal pulse. This is a surge of electromagnetic radiation, including gamma radiation, X-Rays, UV, visible light and infrared, all traveling out at the speed of light. It carries an incredible amount of energy; close to the explosion it’s powerful enough to melt steel and literally vaporize a human body, and even miles away it can start fires and cause severe burns.

This is followed by the blast, racing outwards at high supersonic speeds. The blast pushes a wall of high-pressure air in front of it, creating violent winds. As it starts to run of steam it leaves a low-pressure area behind it; eventually the atmosphere will collapse in to equalize the pressure, creating a second, less intense blast front running in the other direction.

Finally, radioactive fallout will start to fall. Fallout is debris that’s sucked up through the fireball created by the explosion. Along the way it’s pulverized into dust, blasted with high-intensity radiation, heated to very high temperatures and mixed with highly radioactive plasma formed from the remains of the weapon – and up to 99% of the weapon’s mass will be left. If the weapon is an airburst there won’t be a large amount of fallout, maybe as little as a couple of hundred pounds in total. On the other hand if the warhead actually impacts, or even if the fireball touches the ground, there can be thousands of tons of it.

Fallout can continue to descend for weeks, becoming steadily less radioactive as time goes on. Most of the fallout is blown all the way up into the stratosphere, where high-altitude winds can carry it for thousands of miles. It will take several hours for any of this to make it to the ground. Your immediate problem is larger particles and anything that didn’t make it all the way to the top of the mushroom cloud. This will start coming down within a few minutes of the explosion.

So it’s obvious that, before you start worrying about surviving in the post-nuclear holocaust world, there are a few more immediate dangers to get through. It’s also obvious that there’s nothing you can do to guarantee your survival. If a one-megaton warhead explodes 500 yards from you, you’re dead. In fact you’ll be dead before you even see the flash: At that distance, the energy of the thermal pulse will turn you into plasma faster than a signal can get from your eyes to your brain. With any nuclear explosion there will always be a distance inside which survival is just not possible, and with the largest weapons that exist today that could be as much as two or three miles.

On the other hand there’s a wide zone between the distance at which a nuclear explosion will kill you and the distance at which it can kill you. For a one megaton warhead that zone might be seven or eight miles wide. If you’re in that zone you have a much better chance of surviving if you know the nuclear Immediate Action (IA) drill.

The IA drill is your response to a nuclear weapon exploding. You’ll know a weapon has gone off because there will be an extremely bright pulse of intense white light, lasting up to ten seconds. There’s no chance of you mistaking this for lighting or a camera flash going off; it will be far too bright and long-lasting. As soon as you notice the flash carry out this drill instantly:

• Close your eyes. If you’re looking directly at a one-megaton explosion it can cause flash blindness as far away as 13 miles on a clear day; on a clear night, when your pupils are wide open to let more light in, you can be blinded up to 53 miles away. If you are looking in the direction of the blast you can be blinded instantly, but this will probably be temporary and could last anywhere from minutes to a week or two. You still need to avoid permanent damage, so shut your eyes immediately to keep out as much light as possible.
• Turn towards the flash and drop to the ground, with your head towards the direction of the explosion. Anywhere between a couple of seconds and three or four minutes after the explosion, the blast wave is going to reach you. That brings two dangers. First, the air is going to be full of debris that could be moving at more than 2,000mph. A dime-size fragment of brick at that speed has the energy of a rifle bullet. Lying flat will keep you below most of the debris, because irregularities in the ground tend to catch a lot of the low-flying stuff; having the long axis of your body pointing at the explosion will minimize the area exposed to anything that is skimming the ground.
• Keeping your head towards the explosion will also protect you from the blast wave itself. Most of your weight is towards the top of your body, and it’s also a more streamlined shape. As the blast wave passes over you it will tend to pin you firmly to the ground. If it catches your lighter legs first it’s much more likely to pick you up and carry you along, and if that happens you have no real chance of survival.
• Tuck your hands under your body. It’s a natural instinct to shield your head with your hands. Don’t do it. Even a couple of seconds’ exposure to the thermal pulse can cause serious burns; at the very least you’re likely to get the equivalent of moderately bad sunburn. If you get your hands under your body as quickly as possible you’ll minimize their exposure to the pulse, and that’s important. Burns to the top of your head will be painful, but badly burned hands can be a death sentence. If you can’t carry out simple tasks because your hands are covered in third-degree burns, your survival chances drop like a stone. Having your hands under you also makes you more streamlined, and less likely to be picked up by blast.
• Keep your eyes closed. The thermal pulse is energy radiated by the incredibly hot plasma fireball created by the nuclear reactions inside the weapon. It’s the first thing to escape the explosion, traveling at the speed of light. Inside a second or two the shock front of the blast expands out past the fireball, compressing the air until it’s dense enough to block the pulse. This means the glare of the explosion will fade, enough to be noticed through closed eyelids. Don’t open your eyes! In another couple of seconds the air density will fall and the fireball will be revealed again; this distinctive double pulse is one of the unique features of a nuclear explosion.
• Wait for the blast waves. How long it takes the blast to reach you depends how far you are from the weapon. It can be as long as two or three minutes, bust resist the temptation to look for cover before it arrives. Stay flat, head towards the explosion, and wait for it to pass over you. When it does, stay down. Even if people are screaming for help nearby, don’t move. Wait for the second blast wave, coming from the other direction. This will be weaker, so there’s no need to turn towards it, but you still don’t want to be caught moving.
• After the second blast wave, move! As soon as the inwards blast passes over you, get up. You may only have a minute or two before highly radioactive fallout starts coming down, so the priority is to get under cover. Don’t hang around to help people; find something that will keep falling particles off you. If you find something nearby, and you can quickly grab someone and carry them into it, fine – but if you stay in the open for more than a few minutes you’ll almost certainly catch a lethal dose of radiation.
• If you’re within a minute or two of home go straight there. Take off your clothes and throw them out the door, brush your hair thoroughly to remove any dust, then go into your fallout room, put on clean clothes and get into your inner refuge. Stay in the refuge for at least 48 hours, and in the fallout room for two weeks.
• If you’re further from home stay under cover for at least two hours. If you have a gas mask with you, put it on and keep it on. Without going into the open, scrounge up anything that will give you some protection. If you don’t have a mask, wrap clean cloth over your mouth and nose. Cover as much bare skin as possible. If you can find heavy boots or galoshes, put them on. Wrap any spare fabric round your feet and lower legs. Most of the radiation from fallout is alpha and beta particles, and thick cloth will block alpha radiation. That makes a big difference; it’s easier to block than beta, but if it does get though it does a lot more damage.
• Get home as soon as you can. Go directly home. If you can get your hands on a vehicle that’s still running, shut the air vents and drive. If you can’t, try to avoid stirring up dust and walk. When you get home dump your clothes, clean away any dust and get into your inner refuge.

The Immediate Action drill is what you need to carry out if a weapon goes off without warning. What if your town has an air attack alarm and it goes off? There are a few things you can do in the minutes before the explosion. If you’re in a building that hasn’t been prepared, get out. The blast will collapse buildings a lot more easily than it will harm you if you’re flat on the ground; most casualties in urban areas will be injured or killed when a building collapses on them.

There are some places it’s worth sheltering in. Subway tunnels will shield you from the effects of the weapon. Basements can be good shelters if the floor above them is concrete. Narrow trenches are also good, and so are deep drainage ditches. Anything that gets you below ground, but doesn’t risk having a building collapse on you, is good. But if you can’t find safe underground cover, get clear of anything that might be knocked down.

Head for open ground, and when you’re in the middle of it, as far from trees or buildings as possible, stop and wait for the explosion. If there’s water around get in it, and stay under the surface as much as you can. If there’s an obvious target near you, like an airbase or port, lie down with your head facing that way, your hands under your body and your eyes shut. If not, stand there and wait for the flash – then carry out the IA drill.

The nuclear IA drill doesn’t sound like much – lie down and close your eyes? Is that really going to help you when a nuke goes off? Yes, it is. If you’re far enough away from the explosion to avoid instant death, the IA drill will give your chances of surviving a massive boost. It’s also easy to remember. Not many skills are so valuable and yet so simple.