How to Survive a Nuclear Attack

We're living in a dangerous time.

Whether it's North Korea's insane posturing, the actions of a US president described by his own military as easily baited and quick to lash out, or the escalating tensions between a growing number of nuclear states (Russia, India, Pakistan...), the threat of nuclear war feels more credible than it has since the Cold War.

Even if we assume the world's leaders are sane enough to avoid nuclear Armageddon, we're by no means safe. The very existence of nuclear weapons leaves the threat of a world-ending cataclysm hanging over our heads by a very, very fine thread.

The real risk, embarrassingly enough, is accidental strikes.

Amidst the chaos of an international crisis, global catastrophe could arise from a mere technological error — it only takes one falling domino to trigger an avalanche of self-defense responses. - Milo Beckman, FiveThirtyEight

From black bears scaling perimeter fences, to the Northern Lights triggering a state of full alert, the weakest link in the nuclear chain of command has always been plain old human incompetence. But with the stakes so high, that incompetence could be the last action humanity ever takes upon the face of the Earth.

So regardless of the cause, the chances of a nuclear attack aren't to be trivialised. That leaves us to ponder a single, extremely salient question:

How can I survive a nuclear attack?

1) Identifying Attack Targets

When the bombs start to drop (or more likely, the intercontinental missiles start to fly), we want to be far, far away from any location of strategic value, be it a population centre, military base or hub of infrastructure.But if we wait for the missiles to launch, it's already too late. With little more than 4 minutes of warning time, our tactical response to nuclear war will be limited to ducking under a table, curling into a prone position, and kissing our asses goodbye. No. The key to surviving a nuclear attack is preparedness; in this instance, proactively identifying a safe zone, miles away from any likely sites of impact, and heading for the hills at the first inkling of trouble.

By failing to prepare, you are preparing to fail. - Benjamin Franklin

Though identifying sites of military importance may sound impossible (and the sort of activity that could land you in Guantanamo), we have a few declassified government sources we can turn to for inspiration.In the US, the Federal Emergency Management Agency (FEMA) recently released a list of likely nuclear targets from the Cold War. Compiled by intelligence officers during the height of the Cold War, the dossier represents their best guess at locations the Soviets would try and destroy:

How to survive a nuclear attack - US targets.gif

For those of us in the UK, the National Archive released this declassified list of probable targets from 1982:

How to survive a nuclear attack - UK targets.png

And for the rest of the world, we have available a declassified lists of places the US was intent on nuking in the event of a global nuclear conflict:

How to survive a nuclear attack - Global targets.png

Obviously, the military climate has evolved hugely since these targets were picked (otherwise, you guessed it, they wouldn't have been declassified), and it's likely that a modern nuclear attack would follow a very different pattern to that outlined here.

These are historical records and like many other documents released every year by the National Archives have little or no relevance to the present day. - Ministry of Defence

But short of delving into the dark web to trade for state secrets, these educated guesses are the best information source we have. So, using this data, we can piece together a map of likely targets in our immediate area - and begin to identify potential safe zones we could head to in the event of disaster.

2) Calculating the Blast Radius

Obviously, the impact location of a nuclear missile is only half the equation - and we need to understand what the blast radius of an attack might look like.

Nuclear weapons are designed to destroy through several distinct mechanisms: there's the immediate fireball upon detonation; there's an air blast, a shock wave that can flatten entire cities; and there's thermal radiation, capable of causing third degree burns literally miles away from the explosion's epicentre. In order to survive a nuclear attack, we need to be well away from the malign clutches of all three.

The total radius of a nuclear explosion is a function of its yield -  a measurement of the energy released upon detonation - so the bigger the yield of the bomb or missile that hits your local area, the further away you'll need to be to be safe.First, the good news: it's widely accepted that the total yield (measured in megatonnage) of nuclear stockpiles the world over has decreased, pretty radically, since its heyday in the 1950s.

How to survive a nuclear attack - US nuclear stockpile tonnage.jpg


Instead of hoarding world-ending nuclear bombs like the legendary Soviet-era Tsar Bomba - a 50-megaton behemoth, and the largest nuclear weapon ever constructed - the world's nuclear states have switched to smaller stockpiles, filled primarily with (relatively) small yield missiles designed for more precise, surgical attacks.

And that's good news. Really good news.

Because here's what New York would look like if the Tsar Bomba was dropped on it today:

How to survive a nuclear attack - Nukemap 1.png

The image above was generated using the incredible NukeMap - a free-to-use nuclear war simulator, and the perfect tool for working out how far away we need to be from potential target sites.

With a 60km outer radius, residents of New York would have a hard time escaping the Tsar Bomba, no matter how prepared they might be: but thankfully, most modern nuclear weapons fall somewhere in the 1 to 200 kiloton range, or roughly 1/250th the size of the Tsar Bomba.

For context, the UK's Trident missiles are armed with 100 kiloton warheads; the current-generation Minuteman IIImissiles carry 170 kiloton warheads; and best estimates of North Korea's latest missile test suggest a yield in the range of 150-300 kilotons.

If we switch out the Tsar Bomba for a more modern nuclear weapon, with a 200 kiloton yield, we can see the staggering difference in blast radius:

How to survive a nuclear attack - Nukemap 2.png

Instead of a maximum 60km blast radius, we have a reach of 5km; much easier for a New Yorker to survive, especially with adequate preparation. Obviously, this only models a single impact - and it's almost guaranteed that sites of high strategic importance, like bustling population centres and infrastructure hubs, will be subject to multiple impacts - but this process is a good starting point.

By simulating similar detonations on our list of probable targets, we can come up with a list of potential safe zones - areas close enough to be reachable within a few hours, but remote enough to be well away from any potential impact sites.

I live in the UK, and this is what it looks like if you simulate attacks on all of the probable targets identified in the declassified report from the National Archives, and closer to home, my local area:

How to survive a nuclear attack - Nukemap 3.png
How to survive a nuclear attack - Nukemap 4.png

3) Mapping Fallout Zones

With a whole heap of planning, and a whole heap more luck, we might be able to pre-empt potential attack sites, and spot a few likely locations to set-up shop in the event of a nuclear attack.But we before we get comfortable in our fallout shelter, there's just one more factor to consider: fallout.

Nuclear fallout is simply debris and particles which are lifted, or suspended, by a bomb’s detonation and become radioactive and harmful to living matter.The term comes from the fact that this newly radioactive material, usually in the form of dust, literally falls out of the upper atmosphere, hence ‘fallout’. - Scotland's Secret Bunker

This is where things get really complicated: the direction, distance and spread of fallout will vary massively according to the climate of the local area. And, as you can see below, that can have a huge impact on the desirability of your fallout shelter's location.

In the diagram below, we're looking at the same 200 kiloton blast as before, but with NukeMap's fallout mapping enabled. Given their default windspeed and direction, significant fallout from the blast extends almost as far as Boston.

If you're more mathematically inclined than I, you can use NukeMap's advanced modelling features, and FEMA's own rough-guide to fallout patterns (below right), to map the potential fallout zones in your intended safe zone - but for most of us, we'll just have to live with the threat of radiation-induced hair-loss (and hopefully some sweet mutations).

How to survive a nuclear attack - Fallout zones 1.png
How to survive a nuclear attack - Fallout zones 2.png

4) Building a Fallout Shelter

If you've done your homework, mapping out possible target sites and identifying safe zones, when Armageddon comes calling, you'll be able to up and disappear to a remote location, miles away from cities, public infrastructure and military installations.But what do you do when you actually get there?With a nuclear bomb exploding on the  horizon, your best bet for survival is to seek shelter in a building.But as the below FEMA diagram illustrates, not all buildings are created equal.

How to survive a nuclear attack - Fallout shelter.jpg


The numbers in the diagram represent dose reduction: those rooms marked with 200 will successfully reduce radiation exposure to 1/200th of what it would it be outside; those showing 10 will only reduce exposure to a paltry 1/10th.

In the event of a nuclear attack, a conventional one or two story house will provide next to no protection; and according to FEMA's guidelines, if you're caught unawares, your best bet is to seek shelter in a basement or subway station. But as the entire premise of this guide is preparedness, why not go the whole hog, and actually build a fallout shelter?

Instead of cobbling together some extremely amateurish instructions (and risk causing you a cave-in as soon as the blast hits), I'll leave the minutiae of actually building the shelter to more qualified people; but I can still dig-up a few broad guidelines for your build.


A fallout shelter needs to protect you from radioactive particles and blast impact: compacted dirt is great at both. Building down to a depth of about ten feet will provide ample protection, but any deeper makes it hard to dig out in the event of a collapse.


Concrete and steel are cheap, plentiful and tough; perfect fodder for building an effective shelter without breaking the bank.


No matter how well constructed your fallout shelter, there's always a risk of debris blocking your entrance and trapping you inside. Though far from a fail-safe, building a small emergency escape hatch doubles your potential exit routes.


It can be hard to gauge when it's safe to emerge from your shelter, but most estimates suggest a minimum stay of 24-hours, and a maximum stay of 14-days - enough time for the initial radiation to fall to (relatively) safe levels.

It takes at least 14 days for the fallout radiation to decay down to around 1% of its initial radiation.Fallout radiation will probably not be visible to the naked eye so unless you receive an 'all-clear' from a trusted source or you have the training and necessary equipment to detect radiation, your safest bet is to assume that you are within the fallout area and wait out the 14 days. - How to Build a Fallout Shelter


Small shelters may be cramped, but they'll be strong. Stick to the bare essentials: a composting toilet, sleeping area and food/water stash - and use the Swiss government's guideline of nine feet squared of space per person.


There's no sense surviving a nuclear attack, only to emerge from your shelter to a raging inferno, so make sure that anything that could be ignited by thermal radiation is cleared well away from your shelter.

5) Stockpiling Supplies

Whether you've shelled-out for solid-steel silo, or dug-out a ditch in your back garden, your survival depends as much on the contents of your fallout shelter as it does its construction.

Detailing the entire contents of a well-stocked shelter warrants an entire guide in its own right, but to get you started, we can cover some of the fundamentals that every shelter should contain.

Most people would need very little food to live several weeks; however, the time when survivors of blast and fallout would leave their shelters would mark the beginning of a much longer period of privation and hard manual labor. Therefore, to maintain physical strength and morale, persons in shelters ideally should have enough healthful food to provide well-balanced, adequate meals for many weeks. - Nuclear War Survival Skills


Pre-prepared survival food, or military rations (often called MREs), will provide all the sustenance you'll need to survive, while staying fresh and edible for years. Better still, they'll take up minimal space; they don't require any kind of cooking equipment; and they'll contain a balanced range of nutrients and minerals (more than can be said for that bulk pack of Jerky you were eyeing up in Costco).


People can survive a long time without food; less so with water. Recently, the German government made a recommendation to stockpile half a gallon of water, per person, per day, in the event of an emergency.


With your local pharmacy well and truly out of action (and if the Fallout videogame series is to be believed, home to several gangs of violent raiders) painkillers, bandages and antibiotics suddenly became worth their weight in gold.


When nuclear winter descends, you'll be grateful for the warm fleeces and waterproof jackets you stashed away.


If the idea of restarting civilisation without Google at your fingertips phases you (and it does me), go ahead and store an offline version of Wikipedia (yep - all of it) on an external hard-drive. Should you find a way to generate electricity, you'll suddenly be the smartest person in the world.


A wind-up radio will provide contact with the outside world (and hopefully relay that much needed "all clear" message); a lantern will provide light int the gloom of your shelter; a fire extinguisher will, y'know, extinguish fires; a Geiger counter will help you determine the (relative) safety of the world outside; and a map of the local area will help you find your way after you emerge from your shelter.


Sure, there are more practical books you could stash away, but why bother? When you step out into a charred post-nuclear landscape, all thoughts of rearing livestock and restoring community will be out of the window - unless you've read The Roadand by comparison, realise that things could still be worse.


Once you're in your shelter, the hard work is done. You've as prepared as you can be, and now, all that's left to do is ride out the storm - so take a good swig from the bottle of expensive Scotch you squirrelled away, and wait for the thunderous explosions to die down to a quiet murmur.


Most of these supplies will need to be stashed in your fallout shelter, but it's a good idea to hold back a small supply of key survival tools in a bug out bag: a small pack that can be grabbed at the first sign of trouble, containing everything you'll need to make it safely to your fallout shelter. The contents of your bug-out bag will vary according to your own needs, where you live, and your proximity to the shelter, but you can find a good catch-all packing list here.

5) Emerging into the World

You feel safe, tucked up in your steel-and-soil cocoon; and soon enough, the shuddering explosions have fallen quiet.

You wait out the days (at least, you think they're days - it's hard to tell in the perma-twilight of your bunker), reading and re-reading your copy of The Road, chewing on a strip of jerky and sipping on a bottle of whisky - until eventually, you start to think it might be time to step back out into your new nuclear world.

But is it safe?

Hopefully, thanks to the diligent research you conducted earlier, your fallout shelter is a good few miles away from the nearest impact site, and even the wind-borne radiation has missed you entirely. But if you haven't been so lucky, you can dig out your Geiger counter, and try and work out exactly when the outside world will be safe to explore.

One method we could use to estimate this is FEMA's 7:10 Rule of Thumb.

How to survive a nuclear attack - FEMA rule of thumb.jpg

The 7:10 Rule of Thumb states that for every 7-fold increase in time after detonation, there is a 10-fold decrease in the exposure rate.

In other words, when the amount of time is multiplied by 7, the exposure rate is divided by 10.

For example, let's say that 2 hours after detonation the exposure rate is 400 R/hr. After 14 hours, the exposure rate will be 1/10 as much, or 40 R/hr.


The 7:10 rule provides a simple heuristic for translating current radiation levels into future radiation levels.

Using something like the radiation chart below, we'd stand a chance of translating a radiation measurement from a Geiger counter into a prediction of when it would be safe to venture out into the world.

How to survive a nuclear attack - Radiation exposure levels.jpg

The level of risk we'll be willing to tolerate will vary.

Assuming there's some form of government infrastructure left, you may be able to listen out for the all-clear on a local radio station. In that instance, it's safest to sit tight, and wait for radiation to die down to its lowest possible level.

But if the government has disappeared, your exit date will be determined by your rapidly dwindling supplies. At some point, the risk of starvation or dehydration overcomes the threat of radiation poisoning, and you'll be forced out into the world.

Radiation levels up to 1,000mSv are survivable in the short-term, as long as you can quickly relocate to an area free from radioactivity.

If you can find someone brave enough to stick their head out of the shelter to use a Geiger counter, and you have a clear idea of just where you're heading when you emerge, now is the time to make a break for it, and head straight for the isolated farmstead you'd ear-marked during your planning.

6) You've Survived a Nuclear Attack


Thanks to your near-paranoid level of preparation, you've survived a nuclear attack - along with any nearest-and-dearest (preferably capable of reproduction) that you brought along for the ride.

Sure, you might not feel like celebrating - half of the world's population have been atomised, and almost everyone you ever knew is now little more than a shadow, burned into the sidewalk - but you're alive. You've faced-up to the grim spectre of Armageddon, and lived to tell the tale (even if no-one else is around to hear it).

Your vision is pretty blurry from the explosion you just saw on the horizon, and you're starting to cough-up something that looks like lung tissue, but for now, you're King of the Hill; you're the Alpha and Omega. You head for the horizon, determined to start this world afresh, with better ideals than your forefathers that came this close to destroying the world.

You're feeling melancholy from the sheer scale of the loss; but you should also feel elated, because this your chance to make things better. Your paranoia and propensity for isolation, your reluctance to trust other people, your general dislike of humanity, they've all borne fruit - and now the world can be reborn in your image.

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