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How to Survive Nuclear Fallout


It happened. Bright, white light flashed before your eyes, the power of the sun licked your skin, and you felt a shock wave of dust and debris plow through the city you call home. You’re one of the lucky ones, for now, but your struggle isn’t over yet—not even close.

What Is Nuclear Fallout?

After a nuclear bomb is detonated, residual radioactive material is propelled into the upper atmosphere. That material, usually comprised of radioactive dust and ash, then “falls out” of the sky—hence the name. The material can travel for hundreds of miles along natural wind patterns. Exposure to any type of fallout, be it debris, dust, ash, radioactive rain, or anything those materials contaminate, is extremely deadly.

In the short term, exposure to fallout will cause you to become ill, suffering acute radiation syndrome. You’ll suffer rapid cellular degradation and DNA damage and, depending on the dosage, experience nausea and vomiting, adverse neurological effects, and even rapid death. In the long term, pregnant women may miscarry or bear deformed children, your risk for cancer is greatly increased, and you may die a slow, painful death.

Fallout radiation does not hang around forever, though. It decays at a rapid, exponential rate, and many contaminated areas eventually become somewhat safe. Your goal post-blast is to mitigate your exposure to the fallout, find a suitable place for you and your family to hide, and create a feasible escape plan.

The Initial Blast: Destruction, Burns, and Blindness

Anyone within a few miles of the detonation will either be killed instantly or will die very quickly. The epicenter of the bomb dropped on Hiroshima, for example, was estimated to be around 300,000˚C. Body cremations are carried out in furnaces that only reach 1,200˚C. A bomb coming in at 10 KT, which is roughly the size of the bombs North Korea has been testing, would level anything and anyone in a one-mile radius—and that’s one of the smaller bombs out there.

According to Brooke Buddemeier at the Lawrence Livermore National Laboratory, the area between one and three miles out is considered to be the “light damage” zone. Glass will shatter, possibly injuring people, paint will peel, and thermal radiation traveling the speed of light will give exposed skin third-degree burns. At seven miles away, you’d probably get away with just first-degree burns.

Even if you’re 13 miles away from the blast, however, you’ll still be temporarily blinded if you were looking in the direction of the blast (53 miles away at night). And the fallout hazard area (DF zone) at least extends 10 to 20 miles from ground zero.

The First Hour: Find Shelter and Get Clean

Okay, so you survived the blast and you can see the telltale mushroom cloud billowing in the distance. A general rule of thumb (literally), is to hold your arm out if you see a mushroom cloud, shut one eye, and raise your thumb to it. If the cloud is bigger than your thumb you are in the radiation zone and need to either evacuate or seek shelter. You now have 10 to 15 minutes to get somewhere safe. Fallout moves fast and can travel long distances, so you need to seek proper shelter immediately, especially if you are downwind from ground zero. The U.S. government lays out three key factors for finding appropriate protection and avoiding fallout:

Distance

: the more distance between you and the fallout particles, the better. An underground area such as a home or office building basement offers more protection than the first floor of a building.

Shielding

: the heavier and denser the materials - thick walls, concrete, bricks, books and earth - between you and the fallout particles, the better.

Time

: fallout radiation loses its intensity fairly rapidly. In time, you will be able to leave the fallout shelter. Radioactive fallout poses the greatest threat to people during the first two weeks, by which time it has declined to about 1 percent of its initial radiation level.

It’s important you remember these items so you can tell whoever you’re with if you’ve been blinded. Do not try to hide in a car, a trailer, or any kind of vehicle unless you think you can drive away from the area before your 15 minutes is up. If you see a cloud of debris moving toward you, leave the area by a route perpendicular to the path of the fallout. If you’re near a building that can offer better shelter, and you can get there in a few minutes, do so.

The further underground you can go, the better. If you can’t go underground, head to the center of the building. Once you’re inside, shut off ventilation systems and seal the doors and windows.

After that’s done, you need to clean off any radioactive material that may have settled on your body. Failure to do so could lead to “beta burns” on the skin, and exposure to deadly levels of radiation. Instruct everyone who was outside to remove their clothing—at least the outer layers—place it all in a plastic bag, tie it off, then place the bag as far away from everyone as possible. If running water is available, wash your body with lots of soap, wash your hair with shampoo (no conditioner), blow your nose, wipe your eyelids and eyelashes, and wipe your ears. The goal is to remove as much radioactive material from your skin as possible.

The First 24 Hours: Find Supplies and Hunker Down

Now that you’ve found shelter and removed any contaminates, you need to get ready for the long haul. You should expect to stay put for at least 24 hours. Longer if you’re downwind of the blast. It could be a few days, or it could be a month. It all depends on the radiation levels in your area, which will be monitored by emergency personnel. When it’s safe for you to leave, you’ll be instructed to do.

So, you’ll need supplies. First, you need to find drinkable water. Bottled water is your best bet, but if that’s not available, you’ll need to get it from taps that draw from deep wells, water tanks, or covered reservoirs. The types of wells you’d find on a farm or rural home are ideal. Keep in mind, you cannot remove radioactive elements from water through boiling or any type of disinfection. If you cannot find a clean source of water soon, you’ll have to filter some yourself. Your best bet is filtering it through a basic clean earth filter (as shown in the video above), which removes about 99% of the radioactivity in the water.

Next, you need to find an emergency radio that will allow you to listen for updates. You don’t want to be trapped in your shelter for any longer than is necessary. There’s a chance most electronics will not work due to the EMP effects of the blast, and even if they do, you’ll likely experience constant power outages, so a hand-crank emergency radio is your best bet. Make sure someone is always listening for news about what to do, where to go, and any places you should avoid.

But say, as you set up your base, you see someone begin to feel nauseous and display heavy fatigue. Acute radiation sickness is setting in, and you need to help them. If Potassium Iodide (KI) is available in a nearby first-aid kit, administer it to them at the first sign of trauma. There are other ways to manage internal contamination, but Potassium Iodide tablets are the most common. If they don’t start vomiting until four hours or more after exposure, that’s a good sign. They’ll likely recover within a few days or weeks as long as they can stay inside and rest. If they start vomiting within an hour of exposure, go unconscious, or are experiencing seizures, they are in need of serious medical attention and will require aid from a professional.

The First Week and Beyond

Fortunately, you now have shelter and water, so you’re ready to play the waiting game. You may want to try and locate any canned or packaged foods in your vicinity (anything that didn’t come in contact with radioactive particles), but you should be fine for a while if you can’t find any. Be sure to carefully ration and share whatever you do find, however.

Continue to listen to your emergency radio, keep morale up if you’re with others, and check to see if anyone with you is in need of any medications. Some people may be in shock and have forgotten. Waste management will also become an issue, whether you’re sharing a space with people or not. James Roberts and Mark Lawrence at Secrets of Survival suggest a trash can or large bucket should be designated as a toilet, and cat litter can be used to keep smells to a minimum. A little Vick’s Vapor Rub on your nostrils can block out any nasty smells as well.

After the first 24 hours, the fallout will have given up about 80% of its energy, but it’s still best to stay indoors unless told otherwise by emergency responders. Eventually you’ll hear a message and be told to where to go, and how. For additional resources and useful print-outs, check out:

I hope you never need any of this information, but it’s always better to be safe than sorry.