A Brief Introduction to Radiation
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Before we start talking about what actually happened to the Chernobyl power plant, it’s important that you understand how radiation works and why it was such a big deal when the power plant exploded.
Radiation is not like anything that you’ve ever experienced (or should ever have to experience) before. While it is true that the human body is constantly being bombarded with trace amounts of radiation (from neutral sources, like granite rock or x-rays), the amount of radiation that the human body will absorb “naturally” is not enough to do any significant damage to it. In other words, your body does not experience radiation in any noticeable amount.
Radiation is often compared to death, as it is something that you cannot see, cannot feel, cannot smell, and cannot consciously touch. For many people, that is the very definition of death, and being exposed to high amounts of radiation certainly yields a similar result. By definition, radiation is energy transmitted as high speed particles or electromagnetic waves (according to anawa.org.au).
Because of the properties of radiation (cannot be seen, heard, smelled, or felt), radiation poisoning is something that can happen almost totally unnoticed by someone until it is too late. In extremely high doses radiation can burn your skin or nervous system, but most people experience lower doses over prolonged periods of exposure. It is in these situations where radiation poisoning slowly onsets, gradually causing the victim to become more and more ill.
Types of Radiation
The chances are good that you are exposed to some form of radiation every day. Visible light, for example, is a form of radiation, as are television waves, microwaves, radio waves, etc. To generalize and say that all radiation is “bad” is just that- a generalization. In actuality, man-kind utilizes many forms of radiation to its advantage.
To generate nuclear power, however, requires dealing with much more sinister forms of radiation: Alpha, Beta, Neutron particles, and Gamma Radiation. These forms of radiation extend far beyond visible light or television waves, and are extremely hazardous to your health. The fact that these types of radiation are invisible and odourless only adds to their danger.
Alpha radiation is a positively charged particle emitted by radioactive material consisting of two protons and two neutrons. Alpha radiation is extremely dangerous, and is carcinogenic when inhaled or ingested. However, Alpha radiation is also easily blocked- something as small as a sheet of paper can block Alpha radiation. In the event that you were to ingest a form of Alpha radiation, it would transfer its energy over a short distance and damage surrounding body cells.
Beta radiation is a high-energy electron that carries a negative charge. It moves at high speeds and can travel approximately one meter through the air before settling in a low area on the ground. This type of radiation can cause burns, and is very carcinogenic.
Neutron radiation occurs when the nucleus of a heavy element decays into a lighter element and emits a neutron. This type of radiation is the most dangerous for living organisms, yet it is absolutely critical in a nuclear reactor. As neutrons are released from the heavy element (such as uranium), a state called critical mass is reached. Critical mass refers to the state of a reaction whereby it is now self-sufficient and self-sustaining. In the case of an atomic weapon, the reaction is uncontrolled and hence results in a violent “explosion” as tremendous amounts of energy are released. In a nuclear reactor, the reaction is controlled, allowing for the production of heat that can then be transformed into electricity.
Gamma radiation can be compared to x-rays in that they are electromagnetic waves that are emitted from the nucleus (center) of an atom. Gamma radiation carries no electrical charge and is unique when compared to other forms of “heavy” radiation (Alpha or Beta, for example) in that it can pass through living organisms. As it passes through cellular tissue it collides with atoms along its path, creating ions.
The “Half Life” of a Radioactive Element
Alpha and Beta radiation is actually a radioactive form of an element. In Chernobyl, for example, the most prominent radioactive element is Americium. These elements have what is called a “half-life”, or the amount of time (almost always measured in years) it will take for the amount of radiation emitted by these elements to halve. Though the term “half-life” applies to all types of decay, it is most commonly used when referring to radioactive decay.
It is impossible to predict when a single atom will decay, but since we never deal with a single atom (but rather large groups of similar atoms) the period by which the atoms decay is predictable.
Measuring Radiation
A device called a Geiger counter is used to measure radiation. This device measures “roentgen”, the unit by which radiation is measured by. Most North American or European cities experience 10-12 microroentgen per hour, which is roughly the radioactivity of the stone used to construct the buildings and infrastructure. Do you need to be worried that you are being bombarded with radiation? No, as the levels of radiation that the typical person will experience are not high enough to warrant any amount of concern.
That is, of course, unless you reside in a highly radioactive area (such as Pripyat). To give you an idea of what a roentgen is, one roentgen is about 100,000 times the amount of radiation in a typical city. 1,000 microroentgens is equal to one milliroentgen, and 1,000 milliroentgens is equal to one roentgen. So, with all of that in mind, you can rest easy knowing that you are completely safe in a typical urban area.
It takes a dose of 500 roentgens within 5 hours to kill a human, about 2.5 times that to kill a chicken, and about 100 times that to kill a cockroach. In the event of a nuclear war, the Earth will become the roaches.
The only real problem with a Geiger counter is that it can not tell us the extent of an areas radioactivity. It may measure a certain reading in one location, but in reality that is merely the tip of the iceberg. To quote Elena Filatova, “judging a radioactive pocket by its Geiger counter reading is like judging the roots of a tree based on its crown” (I edited the English somewhat). At best, a Geiger counter can give someone an idea of what the ground the stand on is like, but to get the whole story requires complicated testing of the area.
Radiation and Chernobyl
In the days following the explosion radiation levels as high as 30,000 roentgen were recorded in the areas surrounding Chernobyl, though the incredibly high doses of radiation were being emitted by the reactor. Radiation is also not retained by asphalt, so travelling on the established roadways is actually relatively safe. It is when you venture off of the road and onto the grass that the real danger sets in. Though radiation levels that high can not be found in Chernobyl today, the fact remains that radiation is much higher there than anywhere else in the known world (at least for now).
Elena has recorded radiation levels being exponentially higher a few feet off of the roadway than in the middle of road. Radiation is unique in that some areas can be completely radiation free, while a few feet away may be dangerous enough to cause serious illness or death. Chernobyl is now, and for the next several hundred years will be, a deceivingly dangerous place.
Those without education or the equipment to properly measure radiation may find themselves victim to an assailant that can not be seen, heard, or touched.
This is part of what makes Chernobyl what it is today: a ghost town.