Surviving A Nuclear War, Part Two: The Immediate Effects

This is the second part of my article dealing with the survivability of a nuclear war. Part two here deals primarily with the effects of a nuclear blast, and what to do about them. For those who have not read it yet, part one can be found here.

What Happens During a Nuclear Explosion?

Now that you know you really can survive a nuclear war, it’s time to shift the focus to learning about what happens during an individual nuclear explosion. At the end of the day (the world?) you really only need to worry about the bombs that are falling near you, the rest of the war won’t mean a whole hell of a lot to you. Understanding the devastating effects of nuclear weapons is crucial in highlighting the importance of preparation. You can’t prepare for what you don’t understand, and let’s face it, most of us wouldn’t have a clue about what to do in a nuclear attack.

If you wanna know how to survive a nuclear war, knowledge will be a key factor. Learning how it all works is one of the most important preps in your arsenal, and it also happens to be the one you have the most control over. So, let us take a look at what you can expect during a nuclear blast.

Boom Goes The Dynamite

It takes around 10 seconds for the fireball from a nuclear explosion to reach its full size. Such a detonation will release vast amounts of energy in the form of blast, heat, and radiation. An enormous shockwave reaching speeds of hundreds of miles an hour will roll out from the blast, killing people close to ground zero, and causing lung injuries, ear damage, and internal bleeding to those further away. People will sustain injuries from collapsing buildings and flying objects. Thermal radiation will be so intense that almost everything close to ground zero gets vaporized. The extreme heat causes severe burns and ignites fires over a large area, which coalesce into a giant firestorm. Even people in underground shelters face likely death due to a lack of oxygen and carbon monoxide poisoning.

Here’s the worst place to be when a nuclear weapon goes off, other than right next to it: In your car, stuck in gridlock on an exposed highway. Even if you manage to get away from the worst of the shockwave, you and the other drivers will be temporarily blinded by the flash. So you’ll essentially be stuck on a roadway unable to see, and surrounded by other panicked drivers who also can’t see. Great plan.

Still, back in the 1950s some cities did plan to evacuate in case of nuclear war. But times have changed from when nuclear weapons could only be carried by aircraft, and it took quite a long time for one to fly over the pole from Russia. In our modern times, if a nuclear war breaks out you probably only have a few minutes before missiles start hitting their targets. And that is even if your government is timely in letting you know, which is hardly a guarantee.

So, unless you are taking preemptive action to remove yourself from a potential strike area long before such warnings go out, something I highly recommend, it is not a good idea to try and flee ahead of the strike. You probably won’t make it, and actually may end up heading closer to where the thing hits. Once the warning of an inbound strike has been broadcast, it is dice-rolling time.

In those few minutes you may have, there are still things to do.

In the spirit of being redundant, let me say that nuclear detonations create both immediate and delayed destructive effects. There is the blast itself, with an incredible shockwave. Then there is the thermal (heat) radiation, and immediate ionizing radiation that cause enormous destruction within the first few seconds and minutes of the blast. There is also the release of a massive Electromagnetic Pulse (EMP), a blast of energy that has the potential to take out the entire power grid. The delayed effects, such as radioactive fallout and other secondary environmental effects will inflict damage over an extended period afterwards. That period can range from hours to years. Each of these effects is calculated from the point of detonation.

Blast Effects

Most damage comes from the initial blast of the explosion. When a nuclear weapon detonates, it unleashes an insane amount of energy in the form of a shockwave that travels at supersonic speeds. This shock wave of compressed air radiates outward, producing sudden changes in air pressure that can destroy reinforced concrete and steel structures in a split second, and the blast wind that follows can send winds over 650 miles per hour up to 4 miles out from the site of the explosion. For the most part, large buildings are destroyed by the extreme air pressure change, while people and smaller or softer objects such as trees and utility poles are destroyed by the winds.

The magnitude of the blast effect is a function of the height of the explosion above ground level. For any given distance from ground zero, there is an optimum burst height that will produce the greatest air overpressure, and the greater that distance the greater the optimum burst height. Basically, a ground burst on the surface produces the greatest overpressure at very close ranges, but less overpressure than an air burst at somewhat longer ranges. Deciding on whether the weapon is set to hit a hard (bunker) or soft (city) target will determine if it will be a ground burst or an air burst.

When a nuclear weapon is detonated on or near Earth’s surface, as in the case of a ground burst weapon, the blast will dig out a large crater. Some of the material that used in be on that spot is flung out onto the rim of the new crater. But the rest is carried high up into the atmosphere and later drifts back down to Earth as radioactive fallout. An explosion that is at a higher initial altitude than the radius of the fireball it eventually produces does not really make much of a crater and produces very little immediate fallout. For the most part, a nuclear strike kills people more by indirect means later rather than by direct pressure. Unless you happen to be right next to the thing, in which case you will probably never know it.

Thermal Radiation

A good portion of the energy from a nuclear explosion is an intense burst of thermal radiation. Heat, in other words. The effects are kind of like the effect of a long flash from a giant heat lamp. Since this thermal radiation moves along at close to the speed of light, the flash of light and heat goes out ahead of the blast wave by a few seconds, similar to how you will see lightning before you hear the thunder.

The visible portion of the light will produce flash blindness in people who are looking in the direction of the explosion. This will be a burst of light so intense it can cause even cause permanent blindness, burn your skin, or even completely incinerate you where you stand. Anyone who turns to gaze at this sudden flash of light will be blinded by retinal burns up to 40 miles out from the site of the explosion. Quite a bit more extreme than staring at the sun,  this flash blindness can last for a couple of minutes or longer, after which a complete recovery is normal. However, if the flash is focused through the lens of the eye, a permanent retinal burn will result. There were quite a few cases of flash blindness among the survivors at Hiroshima and Nagasaki, but only one real case of retinal burn. Doesn’t sound so bad, right? But still, anyone flashblinded while driving a car could have quite a problem. Even standing still, such a thing causes panic and robs you of precious time you will need to react.

Skin will burn as a result of exposure to higher intensities of light, and this will take place closer to the point of explosion. First, second, and third-degree burns can occur at distances of five miles away from the blast or even farther. Having third-degree burns over 24 percent of your body, or second-degree burns over 30 percent of your body, will result in serious shock, and will probably prove to be fatal unless fast access to specialized medical care is available. Which it probably will not be.

This thermal radiation heatwave from a nuclear explosion can directly ignite just about anything capable of burning. In general, most combustible materials outside the house, such as leaves or bushes, are not surrounded by enough other stuff to generate self-sustaining fires. Fires more likely to spread are those caused by thermal radiation passing through windows to ignite beds and overstuffed furniture inside the places. A secondary source of fires, which might prove to be more damaging in dense urban areas, is more indirect, like damage to stuff inside buildings, such as water heaters, furnaces, electrical circuits or gas lines. These fires would ignite infernos where fuel is in abundance.

Ionizing Radiation

Direct radiation from the blast occurs at the time of the explosion. It can be incredibly intense, but its range is actually very limited. Where air is actually transparent to thermal radiation, that air is more of a barrier for direct ionizing radiation, as it absorbs quite a bit of it. In fact, for large nuclear weapons, the range of the direct ionizing radiation emitted is usually less than the range of lethal physical blast and certainly the thermal radiation effects. That is why, in simulations, you probably will not even see the lines for radiation as they are eclipsed by the fireball.

However, in the case of smaller weapons, direct radiation could be the effect with the greatest range for lethality. Direct radiation did quite a bit of damage to the residents of Hiroshima and Nagasaki, which were tiny weapons by today’s standards. The effects of ionizing radiation on humans is a subject of great scientific uncertainty and intense controversy. It seems likely that even small doses of radiation do some harm.

Electromagnetic Pulse (EMP)

One other lesser-known consequence of a nuclear explosion that can drastically expand its damage zone: an electromagnetic pulse, or EMP.

EMPs are rapid bursts of electromagnetic energy. They occur naturally, most commonly during lightning strikes, and can disrupt or even destroy nearby electronics.

However, nuclear EMPs from a detonation that is large enough and high enough can cover an entire continent and cripple tiny circuits inside modern electronics on a massive scale, according to scientific studies on the subject. The power grid, phone and internet lines, and other infrastructure that uses metal may also be prone to the effects, which resemble those of a devastating geomagnetic storm.

The thing is, nuclear explosions don’t make EMPs directly by themselves. Such an effect requires a couple of necessary ingredients.

The first is the bomb’s invisible burst of gamma rays. A small fraction of a bomb’s total energy yield, about 0.1% to 0.5%, is emitted as gamma rays. These impact hard into molecules of air, knock off electrons and then accelerate the resulting negatively charged particles to pretty close to the speed of light.

Many of these high-speed electrons get shuffled toward the planet’s poles by our magnetic field in a corkscrew-like pattern. The electrons respond to this accelerated motion by letting off some newly acquired energy as a powerful blend of electromagnetic radiation, including radio waves.

That is the electromagnetic pulse. It happens within a fraction of a microsecond, and the resulting surge of energy can overload sensitive electronic devices, especially the kinds we heavily rely on today, such as whatever you are reading this on now.

The energy of this radiation can be collected by metallic and other conductive materials at a great distance, just the same way that radio waves are picked up by antennas.

The energy from the EMP is collected by the receiving material so fast that it produces a strong electric current which can damage any connected equipment. Normally, an equal amount of energy spread over a long period of time, such as in regular radio reception, would have no harmful effect.

When EMP passes through metal or electronic objects like a phone, computer, or radio, they can absorb this incredibly powerful pulse. That generates a rogue current of electricity that moves through a modern device’s fragile circuits and can disrupt or even fry them completely. Power transmission or telecommunications equipment, meanwhile, can overload from the excess current, short out, and end up failing for miles around.

Altitude plays a critical role in the generation of an EMP. Nuclear detonations that occur many miles above the surface can have devastating consequences compared to those that happen on the ground or very close to it.

At a great altitude or high elevations, the gamma rays can more easily spread out, hitting many more upper-atmosphere air molecules over a much larger area. The lower density of the air allows molecules to move about more freely and maximize the intensity of an EMP. A high-altitude nuclear detonation could create an EMP that might wipe out the power grid of an entire country, or more.

When an explosion happens closer to the ground, however, a lot of those gamma rays would slam into the earth and other objects. They would then have a harder time creating a large enough electric field to generate widespread EMP. And the greater density of the air wouldn’t help, either.

In most probable scenarios, the EMP of a lower yield and closer to the ground explosion would result in an EMP not reaching much farther than the close in destructive radius of the blast effects and intense thermal radiation. In that case, such a nuclear blast would give you quite a bit more to deal with than a bricked cellphone or power loss to your Tesla.

Basically, you probably won’t survive inside this zone anyway, which can stretch a couple of miles in diameter for a larger weapon. And if you did manage it, you’d be more occupied climbing out of the radioactive rubble than checking in on Facebook to see what the hell just happened.

It’s more probable that within about 5 miles of ground zero, you may have more of a disruptive impact, which doesn’t fry your equipment so much as cause it to crash until restarted.

There are all sorts of variables that determine whether or not an EMP affects electronics. Things such as the size and location of it, the structure of the building it is in, whether it is plug-in or battery operated, if it has a surge protector, and so on.

Since most radios have simpler, less fragile circuitry than a phone, especially survival-type radios, they are more likely to be a first line of information after a nuclear blast. Assuming that radio transmission towers outside of the impacted area will still be able to send information, they will be an invaluable tool to use to find out that you just got hit with a nuke. Which you may have already guessed.

The Delayed Effects of the Aftermath

Those who grew up during the Cold War, or at least watched most of the movies, have memories and beliefs shaped by the popular ideas of the time about nuclear weapons. This has gone a long way towards creating a fatalistic outlook about nuclear warfare that still persists today. I don’t mean to downplay in any way the wholesale destruction that will come with an all-out nuclear war, but there are a great many factors that are misunderstood. There is quite a bit of information available today that dismantles many of the common misconceptions that are often held by individuals and communities.

There are two big ones among those misconceptions.

The first is that casualties due to a nuclear detonation are pretty much predetermined, mostly by location, and that there is nothing to be done about that in the event of a nuclear strike. But the truth is that, while those within the blast radius itself are probably done for, those in danger of death due to exposure from exposure to fallout can actually be prevented.

The second biggest misconception is that sheltering in the right place—not fleeing the area—is always the safest thing to do after a nuclear attack. Again, not true. There are a variety of different factors to consider, and sometimes getting the hell away is exactly what you should do. Other times, digging in might be for the best.

In examining those factors, the first difference will be the delayed radiation and fallout, and to understand how to deal with it, we first have to understand what it is.

Fallout: IRL Edition

Fallout consists of the radioactive particles that fall back to Earth as a result of a nuclear detonation. It is made up of weapon debris, remains of the weapons fission material, and, irradiated soil that was kicked up primarily in the event of a ground burst. The particles of all this radioactive material vary in size from invisible dust to actual pebbles. A good portion of this stuff falls directly back down to earth close to the source of the detonation, or ground zero, within a few minutes after the explosion, but some get blasted high into the atmosphere. This portion of it will be dispersed over the ground during the following hours, days, and months. Fallout can be defined as one of two types: early fallout and delayed fallout. The early wave comes mostly within the first 24 hours after the explosion, and the delayed stuff occurs days or even years later.

The greatest part of the radiation hazard from a nuclear burst comes from short-lived radionuclides that are generally confined to the areas downwind of ground zero for the explosion. This radiation hazard comes from radioactive materials with half-lives of seconds to a few months and from dirt and other stuff present in the vicinity of the burst that was made radioactive by the reaction of the weapon’s detonation.

Most of those particles will decay rapidly. Still, even beyond the blast radius of the detonation, there would be hot zones that survivors would not want to enter because of contamination from long-lived radioactive isotopes. For the survivors in a nuclear detonation area, this lingering radiation could still be a grave threat even several years after the explosion.

Predicting the amount and levels of the resulting fallout from a nuclear blast is difficult because of a few different factors. The most significant of these are the yield and design of the weapon, the area and altitude of the explosion, the type of ground underneath the point of detonation, and the current weather conditions in the area, especially wind direction and speed.

Short-lived isotopes from the detonation radiate their energy pretty rapidly, creating intense radiation fields that also decline quite quickly. Long-lived isotopes release energy over longer periods of time, creating radiation that is much less intense but more persistent over time. Fission products thus initially have a very high level of radiation that declines quickly, but as the intensity of radiation drops, so does the rate of decline.

A useful rule to keep in mind is the “Rule of Sevens”. This rule states that for every seven-fold increase in time following a nuclear detonation, starting at or around the one-hour mark, the radiation intensity decreases by a factor of 10. So after 7 hours, the residual radioactivity of these particles declines by 90%, to one-tenth its previous level of 1 hour. After 7×7 hours, 49 hours, or approximately 2 days, the level drops again by 90%. After 7×2 days, so 2 weeks, it drops again by another 90%, and so on for 14 weeks. The rule is pretty accurate for the first couple of weeks, and roughly for the first six months. After those six months, the rate of decline in accuracy becomes much more rapid.

I will leave the science-speak at that. For those who want to peruse more in-depth information, I would suggest The Atomic Archive: effects of nuclear weapons, and for those of you who really have an enormous amount of time to spare and love the hell out of some math, I suggest the most comprehensive source I have found for scientific information regarding nuclear war, The Nuclear Weapon Archive.

Remember, an air burst type of detonation can result in only minimal radioactive fallout if the fireball doesn’t hit the surface. In the case of a ground burst, a nuclear explosion set off on or close to the surface, the blast can create very significant levels of contaminated fallout.

Many of the various fallout particles are extremely hazardous biologically, due to the types of radiation released, and avoidance of fallout is going to be the primary concern for those who are far enough away to survive the initial blast and thermal radiation (heat) that can travel quite far.

How Radioactive Fallout Affects the Human Body

Assuming you have survived the initial blast – basically a fast-moving shock wave of pressure and heat – that fries everything in the surrounding area, now you must deal with the fallout. There is a lot of scientific information available that I am not going to pretend to be an expert on by discussing here. The particulars of the radiation are not of immediate importance. Avoiding it is. So, let us simplify. The good thing is that the radiation is probably the one threat to your from a nuclear detonation that you can actually have some say over mitigating.

There are three primary types of radiation released in a nuclear explosion that we need to concern ourselves with. These include:

Alpha radiation. Alpha particles come from the decay of the heaviest radioactive elements, such as uranium, radium, and polonium. This type is the simplest to avoid as it is stopped by just about any barrier, even cloth. Your skin is a decent barrier as well, although you must avoid taking it by ingesting it, breathing it in, or getting it in any open cuts or wounds.

Beta radiation. Beta particles are most hazardous when they are inhaled or swallowed. This is also stopped by barriers, although not as easily as alpha radiation. It can enter the body through ingestion, breathing, and even through the eyes.

Gamma radiation. Gamma rays are photons, pretty much like light, except they have more energy and can easily pass through several inches of a heavy material such as lead. This is unfortunately also the most deadly form of radiation, causing radiation sickness as well as long-term effects such as thyroid disease and cancer.

Certain parts of the human body are specifically affected by exposure to different types of radiation sources. Several factors are involved in figuring out the potential health effects of exposure to radiation. These include:

1. The size of the dose (amount of energy deposited in the body)
2. The ability of the radiation to harm human tissue
3. Which organs are affected

The most important factor is the dose of radiation. The amount of energy that is actually deposited in your body. The more energy that is absorbed by cells, the greater the damage done to them. The absorbed dose, the amount of energy absorbed per gram of body tissue, is usually measured in units called rads. Another unit of radiation is the rem, or roentgen equivalent in man. To convert rads to rems, the number of rads is multiplied by a number that reflects the potential for damage caused by a type of radiation. For beta and gamma radiation, this number is generally one. For some neutrons, protons, or alpha particles, the number is twenty. Definitely want to avoid those pesky alpha particles, yeah?

Here is a useful chart:

Symptoms of Radiation Sickness

The initial signs and symptoms of acute radiation sickness are usually nausea and vomiting. The amount of time between exposure and when these symptoms develop is a good clue about how much radiation a person has absorbed. If it starts soon and progresses quickly, that is a bad sign.

After the first round of signs and symptoms, a person with radiation sickness may have a brief period with no apparent illness, followed by the onset of new, more serious symptoms.

If you’ve had a mild exposure, it may take hours to weeks before any signs and symptoms begin. However, with severe exposure, signs and symptoms can begin minutes to days after exposure.

Possible symptoms include:

Nausea and vomiting; Diarrhea; Headache; Fever; Dizziness and disorientation; Weakness and fatigue; Hair loss; Low blood pressure; Bloody vomit and stools, indicating internal bleeding.

We will not get too far into the effects of radiation poisoning here, as there are far better sources of that information than I. Such as this. For an even greater batch of information to titillate those few hardcore scientists who are very doubtful to be reading this article, I would suggest the massive database of the Radiation Effects Research Foundation, which is a cooperative effort of U.S. and Japanese scientists to research the effects of radiation from the use of nuclear weapons specifically. Being as these two nations have the most, ahem, experience in such things, the RERF is one of my trusted sources for data.

In short, “avoid it” is the most important thing I have to say about radioactive fallout.

And so, with that we will conclude part two of this series. We are moving right along. Part one showed us that, yes, we can actually survive a nuclear war. Now here in part two we have learned exactly what the dangers of nuclear strikes really are. Part three will be the conclusion and will get into exactly what you can do to avoid or mitigate the effects of a nuclear strike, how to survive if one does occur near you that doesn’t kill you outright, and also some possible things to do now that might reduce such chances of being under the damn thing in the first place.

Stay tuned.