Radiation Issues In Nuclear Blasts
Radiation Issues In Nuclear Blasts- Part 1, by Dr. Bones of doomandbloom.net – Survival Blog
Although many don’t view a nuclear event as a likely disaster scenario, it’s important to learn about all the possible issues that may impact your family in uncertain times. Given the instability in the Korean Peninsula and elsewhere, the issue of nuclear blasts and the radiation they emit is a timely subject.
Understanding the Definition of Radiation
The quick definition of radiation is energy given off by unstable matter in the form of rays or high-speed particles. The following is some basic chemistry paraphrased from the U.S. Nuclear Regulatory Commission (US NRC): All matter, including you, is composed of atoms. Atoms are made up of various parts; the central nucleus contains minute particles called protons and neutrons, and the atom’s outer shell contains other particles called electrons. The nucleus has a positive electrical charge, while the electrons have a negative electrical charge. Neutrons are, well, neutral. These entities work within the atom toward a stable balance by getting rid of excess atomic energy (called radioactivity). Unstable nuclei want to become stable and may emit energy; this emission is what we call radiation.
Types Of Nuclear Weapons
Until the recent missile launches by North Korea, most people were concerned about the use of “dirty bombs“ by terrorists. A dirty bomb is not technically a nuclear weapon. It uses conventional explosives to disperse radioactive material in the general area. Usually, the effect of the explosion causes more damage and casualties than the radioactive elements.
Our concept of an “atomic bomb“ as developed by the Manhattan Project in the 1940s is one that uses “nuclear fission”. The explosion is caused by a chain reaction that splits atomic nuclei. The result is a wave of intense heat, light, pressure, and kinetic energy equaling thousands of tons (also called kilotons) of TNT. This is followed by the release of radioactive particles in a cloud that resembles a mushroom (if a ground blast). Mixed with dirt and debris, the particles fall back to Earth, contaminating crops, animals, and people. This will happen in the area of the detonation but will also be blown elsewhere by the prevailing winds.
Atomic bombs gave way to hydrogen bombs. These are best described as “thermonuclear” weapons due to the generation of extreme heat during detonation. H-Bombs use a process known as nuclear fusion, which takes two light nuclei and forms a heavier one, using variations of hydrogen atoms called “isotopes”. This fusion process requires high temperatures and usually involves a fission reaction as discussed above to initiate. H-Bombs don’t just generate power in the kilotons; they can reach levels in the megatons (millions of tons) of TNT.
Another type of thermonuclear weapon is the “neutron bomb“, which generates much less kinetic energy and thermal damage but much more radiation. Enhanced radiation weapons like the neutron bomb generate a fusion reaction that allows neutrons to escape the weapon with only a limited blast. Originally designed by the United States to counter massive Soviet tank formations, the neutron bomb is an example of a tactical nuclear weapon. The effect is to leave infrastructure mostly intact while wiping out human targets due to massive radiation.
Damage Caused By A Nuclear Attack
The impact of a nuclear bomb is dependent on its “yield”—a measure of the amount of energy produced. The Hiroshima A-Bomb had a yield of 15 kilotons, while the “Tsar Bomba”, detonated by the Russians North of the Arctic Circle in 1961, had a yield of 51 megatons (51,000 kilotons!). Most of the weapons stockpile of the U.S. and Russia consist of bombs in the 100 to 500 kiloton range, much stronger than Hiroshima and much weaker than Tsar Bomba. This is because they are meant to be fired at major cities in clusters rather than one large bomb, which would be easier to intercept than, say, 20 smaller ones.
What Causes Damage
Damage is caused by:
- Blast effects (kinetic energy) – damage due to the explosion and resulting shock wave
- Heat (thermal energy) – damage generated by extreme heat
- Radiation (initially and later via fallout) – both local and, later, far-reaching
- Electromagnetic pulses (EMPs) – disrupts telecommunications, infrastructure
You can expect a generally circular pattern of local damage, but various factors come into play besides the yield of the weapon. The altitude of the explosion, weather, wind conditions, and nearby geologic features play a role. The U.S. government estimates the distribution of damage for fission bombs as the following:
- 50% shockwave
- 35% heat
- 5% initial blast radiation
- 10% fallout radiation