Russia’s threat to use strategic nuclear weapons in its war on Ukraine has been widely discussed.
Russia is estimated to have thousands of strategic nuclear weapons – possibly the world’s largest stockpile – that could be deployed at any given time. The use of nuclear weapons is also embedded in Russian military doctrine. Ukrainian President Volodymyr Zelensky has urged the rest of the world to take the threat seriously.
In this article we examine what would happen during a tactical nuclear bomb detonation, including three stages of ignition, detonation and radioactive fallout – and how one might avoid it.
You suddenly see a glow in the sky, which is as bright as (or even brighter than) the sun. You quickly turn your back and run to hide.
The flashes suddenly disappear, but return after a while and continue – the typical double flash due to the competition between the fireball and the shock wave. It gets incredibly hot and bright, and you shield your eyes to avoid retinal burns.
The intense thermal radiation also possibly burns the skin through your clothing. Wearing light colored clothes or staying indoors will help.
You’ve also got a substantial dose of invisible nuclear radiation: gamma rays, X-rays and neutrons. You find cover to shield the worst heat and radiation.
Now that you’ve survived the first seconds of a nuclear explosion, expect a “tactical” bomb smaller than Hiroshima (which was equivalent to 15 kilotons of TNT).
The fact that you’ve lived for so long means you’re on the periphery, not ground zero. But to survive the next few seconds, you have to do some things.
Then the blast wave will come. It consists of an overpressure shock wave, followed by an outward blast wind, often with the opposite wind returning to ground zero.
It will destroy or damage all built structures within a certain radius from the epicenter, depending on the yield and height of the explosion.
For example, a 15 kiloton bomb would have a fireball of about 100 meters and would cause complete destruction up to 1.6 kilometers around the epicenter.
A kiloton bomb – similar to the 2020 ammonium nitrate explosion in Lebanon’s capital Beirut – would result in a fireball of about 50 meters with about 400 meters of severe damage.
Shock wave travels faster than the speed of sound (about 343 meters per second). So if you are one kilometer away from the epicenter of the earthquake, you have less than three seconds to find cover. If you are five kilometers away, you have less than 15 seconds.
You will need to protect yourself from thermal and nuclear radiation, as you can die if exposed. However, you should find somewhere safe – you don’t want to be crushed into a building destroyed by an explosion.
Go indoors, and preferably in a reinforced bunker or basement. If you live in a brick or concrete house with no basement, find a sturdy part of the building. In Australia, this would be a small bathroom at ground level, or a laundry with brick walls.
The incoming shock wave will reflect off the interior walls, superimposing with the original to double the pressure. Avoid the blast side of the building and be sure to lie down instead of standing.
If there is no reinforced room, you can lie down (not under) under a sturdy table or next to a bed or sofa. If the concrete slab falls down you could be crushed under a bed or sofa.
Stay away from doors, tall furniture, and windows, as they will likely break. If the walls come down, you’ll have a chance to survive in a pocket in the rubble.
If you are in an apartment building, run up a fire ladder in the building’s structural core.
Avoid wood, fiber cement or prefabricated structures (which comprise most modern housing in Australia) as these will probably not survive. And as the blast comes, open your jaw so that your eardrums get a pressure wave on both sides.
The third stage is Fallout: a cloud of toxic radioactive particles from the bomb will rise during the explosion and be deposited by the air, contaminating everything in its path. This will continue for hours or possibly a few days after the eruption.
In comparable British-Australian bomb tests at Maralinga, the result was clearly preserved in the desert along a kilometer-wide track, 5–25 km from ground zero.
You must protect yourself from the consequences or you will have a short life.
If you are in a stable structure such as a basement or fire stair, you can shelter in place for a few days if necessary. If your building is destroyed, you will need to move to a nearby intact structure.
Close all doors, windows and air gaps. You can drink water from intact pipes and eat from sealed cans.
For outdoor movement, any PPE available should be used – specifically a P2 mask, or even a dust mask. While tactical nooks are designed to destroy personnel or infrastructure, they still allow troop movement under cover of explosion. The radiological hazard is significant, but must be lived.
A radiological weapon, on the other hand, would intentionally increase the dose of radiation to the point of being lethal.
Once you find shelter, you’ll need to disinfect. This will require a thorough cleaning of the skin, nails and hair, and a change of clean clothing. But any severe burns must be healed first.
It is expected that by now the national authorities would have come forward for rescue and medical treatment.
Robert K. Niven, Associate Professor, Australian Defense Force Academy, Chi-Qing Lee, Professor of Civil Engineering, Australian Defense Force Academy, Demit Mohoty, Senior Lecturer in Civil Engineering, Australian Defense Force Academy, and Paul Hazel, Professor of Impact Dynamics (UNSW Canberra), Australian Defense Force Academy
This article is republished from The Conversation under a Creative Commons license. Read the original article.