The Facts Of Nuclear Radiation & Survival

The consequences of big nuclear events spread far beyond the borders of the cities and countries immediately affected, but just how far?

The consequences can range from minor inconveniences, like after the Chernobyl disaster europe could not eat salad leaves for many months, while in Hiroshima and Nagasaki the toxic black rain was clearly devastating.

The result of any major nuclear event will be fallout, be it a meltdown at one of the world’s nuclear facilities, a terrorist attack dirty bomb or full-scale nuclear war, fallout will be a fact of life for everyone in the vicinity.

Although, fallout isn’t nearly as instantaneous, or destructive and unpredictable as a nuclear blast or meltdown, you can prepare for and plan your way through nuclear fallout.


So, lets take a deeper look at nuclear fallout.

Most importantly, lets explore a few things that you can easily do to prepare and potentially survive short-term exposure to nuclear fallout as you make your way to safety.

First, there’s the location of the explosion.

If it’s an airburst, then comparatively little fallout will be produced (but there will be a substantial EMP wave), if it’s a surface explosion, material will be pulled up into the nuclear cloud and irradiated before it’s carried along the plume into the upper atmosphere.

Explosion over water would be more favorable...not the case.

The explosion evaporates water, irradiates the sea salt, producing a much finer, smaller fallout that can spread across a much larger area. This fallout will seed clouds and rain back down on cities hundreds or thousands of miles away.

The second key factor is meteorological.

Nuclear fallout is determined by the way the wind blows. Due to the fine particulates produced by a nuclear blast, fallout can easily be carried over hundreds of miles in a matter of hours and days. Of course, the greatest fallout is felt in the immediate area of the nuclear event, but radioactive material can spread far and wide due to its volatile nature.

Animals may graze in fields covered in nuclear fallout, in some cases prompting their extermination (as in Chernobyl) before they can spread the fallout further by carrying it in their fur, their droppings and their bodies.

Crops might be dusted with fallout from an explosion hundreds of miles away, as was the case with the salad leavesmentioned above. These plants have to be safely destroyed to contain exposure.

The Critical First 72 Hours...

The reality of a nuclear explosion and the fallout that comes with it is overwhelming to think about. But, it’s not a totally hopeless situation...Akiko Takakura was just 300 meters from ground zero at Hiroshima, he survived unscathed. Eizo Nomura was also just 170 yards from a nuclear explosion and lived into his 80s.

How did they possibly survive a nuclear bomb going off right on top of them…while so many perished? In reality, there are 4 key factors that will determine whether you’re safe from the fallout of a nuclear explosion or meltdown…

Time is crucial after a nuclear blast...

You have about 15 minutes to seek sufficient cover, radiation will die down to acceptable levels in most of the blast area after just a few days. Fallout is at its absolute worst in the first 72 hours, so it’s crucial to evacuate immediately or stay sheltered. After a few weeks, you’ll be able to make longer trips outside.


After time, the initial fireball and scorching thermal radiation of a nuclear explosion gives way to Gamma radiation.

Gamma radiation is very powerful, able to penetrate inches of heavy material and rapidly poison the body, so shielding can play a vital role in protecting you from radiation. Both of the Hiroshima survivors mentioned above were underground in a shielded concrete basement, which was the key to their survival.

How you might really survive a nuclear event…

Your very first priority in the first crucial minutes will be finding the best possible shelter nearby. You’ll have 15 minutes or less to do so. Remember that cars provide absolutely no protection and that any shelter is better than being outside.

Once you’ve found the right place, go to the deepest room inside it. You’re basically trying to put as many walls as possible between you and the outside world, even if that means holing up in a linen closet. You’ll want to make sure you’re away from doors, windows and anything else that might be exposed to the outside world...It’s even a good idea to tape up the cracks around doors and windows, to prevent particulates from seeping in.

Once you’re confident in your shelter, you’ll want to gather supplies. We’ll talk more later about which supplies are best to keep on hand (ideally you’ve got a bug-out bag), but you’ll want to lay hands on as much food, water and other essentials as you can find without leaving your shelter. Once the fallout sets in, it won’t be safe to eat anything from outside your shelter.

OK, Reasons To Think Positive If The Worst Happens...

  • First, most modern nuclear weapons have a blast zone of about 1 mile. For meltdowns, the most severe area of exposure will be even smaller. If you’re outside this small radius, you’ve already dodged the greatest risk of fatality.
  • After the initial blast, you’ll have about 15 minutes to seek shelter before the fallout begins to set in. This gives you enough time to find the best possible shelter in the immediate area without exposure.
  • It might seem ideal to have a hazmat suit and expensive kit on hand at this point, but the best thing is good old-fashioned shelter; namely concrete. That’s ultimately the best protection for those first crucial days.
  • Time to take a single dose of Radiation Blocking Iodide such as Life Extension Potassium Iodide Tablet.
  • While fallout and the aftermath of a major nuclear explosion will obviously last for years, you should be through the absolute worst of it in just 72 hours.

In the immediate aftermath of a nuclear explosion, radiation levels will typically be extreme and fallout will be at its worst. This is when you’re most likely to see effects like the black rain that came down on Hiroshima after the nuclear explosion there.

Fortunately, the worst of this fallout will dissipate quickly. In some cases, radiation levels can drop from as much as 1,000 roentgens/hour to as little as 10 roentgens/hour in just the first three days. That’s why it’s so crucial to stay inside, away from windows and doors during the entire first 72 hours.

This is where a radio can come in handy, giving you a crucial lifeline to the outside world. Because, for the next 72 hours, you’re going to want to stay buried as deep as possible in your shelter while the intensity of radiation outside plummets to more livable levels.

After that, in many cases it should be safe for short trips outside. Of course, there’s no guarantee, as each nuclear event plays out differently. Regardless, by the 72-hour mark you can start thinking about making your way to safety or at least assessing your surroundings.

A small article by the New York Times How to Build A Nuclear Shelter Here.