Protecting Yourself from Fallout

What is Fallout

Simply put, fallout is radioactive dust created when a nuclear explosion throws dust and dirt (made radioactive by the bomb) miles into the air. The heaviest dirt and dust “fall out” and land downwind of the explosion, creating “hot zones” or areas of radioactive danger outside the area where the bomb’s explosive effects are felt. It is people caught in these zones that will need to shelter underground or in fallout shelters to avoid death and serious illness from radiation poisoning. So in a nuclear exchange between India and Pakistan, this will be in Pakistan and points east, including India and parts of China. (Korea, Japan and other parts of Eastern Asia will also suffer from fallout, though less than in the immediate area downwind of the detonations.)

Whether there is an exchange in the Middle East, the Korean Peninsula or India, none of the heavy fallout will reach the United States, but lighter particles are carried by the winds for thousands of miles and may drift to the ground days or even weeks later. These particles could reach the West Coast of the United States a week or so after the initial explosions. Some parts of the country could miss the fallout entirely as the jet stream and prevailing weather conditions will carry it across some regions wile avoiding others. The government and major broadcasters will track the fallout clouds, juts as they track hurricanes. Again, keeping informed (Rule 2) will help you plan to avoid the fallout danger.

The good news is that the radioactive isotopes degrade and lose their radioactivity relatively quickly over time. So a particle of fallout that lands on Korea two days after an explosion is only 1/100th as dangerous as the fallout than landed during the first hour. And the fallout that drifts to earth two weeks after an explosion is only 1/1000th as dangerous as it was in the first hour after the explosion.

Fallout particles that land on your home and nearby can be disturbed by the wind and washed away by rainwater or a blast from your hose. While this means that a good rain should wash away much of it and reduce the level of ambient radiation, it also means that fallout may be washed into low lying areas where puddles form leaving behind pockets of higher background radiation. Having a good Geiger counter can help identify these areas and other hot spots both during fallout and afterwards. While expensive, a Geiger counter takes the guesswork out of exposure monitoring.

Protect Yourself from Fallout

Even low levels of radiation can be dangerous when you are exposed for prolonged periods of time. And it is especially dangerous to young children, who should be protected to the greatest extent possible. If you cannot avoid being in an area where fallout lands, then you should minimize your exposure and create a barrier between yourself and the fallout. This is especially important for young children and pregnant women.

Dirt, concrete, bricks and other dense, solid objects offer the best protection from fallout. While people immediately downwind of a nuclear event should have at least three feet of cement or four feet of dirt around them to form a good fallout shelter, a traditional basement offers significant protection from the low levels of fallout expected in the United States after a bomb blast in Asia or the Middle East. Once fallout is predicted to start, sleep in the basement, especially along the walls that are underground, to enhance the minimal protection offered by your house. Pile items on the floor above you – such as books and heavy or thick furniture, because everything between you and the fallout on your roof will offer you some degree of protection, and when dealing with long-term exposures, even a slight improvement in your protection is worth it. If you do not have a basement, sleeping in an interior room as far as possible from exterior walls and the roof will offer a small degree of protection. Again, pile thing along the outside of the walls and floor above the room to absorb as many rays emitted by the fallout as possible.

Some people advocate piling dirt on the floor of the room above the basement in which you are sleeping. While this will absorb additional radiation, it is not likely to be necessary with the low levels of radiation expected from blasts on the other side of the pacific. If terrorists hit Seattle, however, and you are down wind 1,000 miles, that could be a different story. Again, a Geiger Counter will help you determine this, as will watching the newscasts. Should a nuclear bomb detonate closer to your home, this might be a good spur-of-the-moment tactic to consider.

The most dangerous form of fallout is particles that you breathe in, as they will expose your internal organs to whatever radioactive power they posses. So do not go outside during periods of active fallout and avoid breathing unfiltered air at any time the forecast predicts heavy fallout. Also during period of fallout, turn off heating or air conditioning systems that bring outside air into the house, unless they are equipped with a HEPA filter (and few residential systems are). Dusts masks will help some, N95 or N100 particlate masks will help more and gas masks with a NBC (nuclear, biological and chemical) rating will provide the best protection. Also, if you go outside during periods of fallout, avoid bringing clothes contaminated with fallout into your house. Remove your clothes and wash yourself under a hose to remove accumulated fallout. Leave the clothes outside to be disposed of or decontaminated later. Once inside, immediately shower again with a good soap to remove radioactive particles from your skin and hair. This will protect you and other members of your household.

Take Potassium Iodide or Iodate

One proven long-term effect of exposure to low levels of radioactive fallout is cancer of the thyroid. This is because the thyroid absorbs radioactive iodine, concentrating the dangerous isotopes and causing long-term harm. You probably won’t get sick that week, but years down the road it could cause serious problems, including cancer. Medical science has demonstrated that by taking potassium iodide or iodate orally before and during fallout, the thyroid will be flush with iodine and, as a result, will not absorb damaging amounts of radioactive iodine isotopes. You should obtain a source ahead of time, as the pills can be safely kept for years. You can order these products online or talk to your pharmacist. Some communities are providing pills to consumers who live near nuclear plants.

Do not Ingest Fallout

In Russia, cows downwind of Chernobyl ate grass that had radioactive particles on it. Radioactive isotopes were excreted in their milk, which was then consumed by children, to their detriment. In other places, crops with fallout on them were consumed. So be careful not to gather food during or shortly after periods of fallout. Do not drink fresh milk after fallout. Vigorous washing will reduce fallout on vegetables, and peeling items will also remove it. But care must be utilized for a year or more to avoid consuming reductive particles. Canned food and other commercially packaged food that was grown and packaged prior to exposure to fallout will be safe as long as the packaging is well sealed and the containers are rinsed before opening.

If you drink water from surface sources – such as ponds, rivers or streams – or collect rainwater, it must be filtered to remove tiny radioactive particles. The water itself will not become radioactive, but fallout particles in it will need to be filtered out. And remember that when enough particles are trapped in your filter, it will be radioactive, so don’t store it in your shelter.

Minimize Exposure to Fallout

Every day the sun shines, your body absorbs radiation, but the gamma rays and other radiation you can pick up from fallout is much worse than a sun burn. Radiation sickness is serious and high levels of exposure are terminal. Your goal is to minimize exposure to radiation by:

  1. Reducing its intensity by blocking it with mass (dirt and concrete or even books, stacks of newspaper or water) and the passage of time (its power fades over time).
  2. Reducing avenues of exposure by filtering drinking water and washing foods, so that you do not ingest it, and by filtering the air so you do not breath it.
  3. Reducing the time you are exposed to radiation by taking shelter. The longer you can stay in your shelter (basement) the better, especially when fallout is predicted.

Continue to part 3, Nuclear War: Planning and Preparig for the Worst

Go back to part 1, What to do if Nuclear War breaks Out


When I was a young and impresisonable prepper, I hung out at the website where the following was originally published. The site is long gone, but some of their content lives on. For example, I had this saved on my hard drive.

As near as I can tell, this was written at some point between 1999 and 2004 and it focused on war in the Middle East, not an attack on our homeland. Don’t expect it to be 100 percent up to date or to pertain to a nuclear war started by Russia. Still, the information on fallout remains accurate.

-Pete