In the modern world uses many natural phenomena in order to achieve the noble goals.I was no exception and radiation.Without it difficult to deliver adequate diagnosis and verify the integrity of components.But this leads to the fact that the rate of background radiation varies depending on the place of residence or work.People every day receives a portion of the radiation.When it is necessary to take measures to reduce the negative effects on the body?
General information about radiation
Before we talk about what the rate of background radiation is acceptable for a man, you need to understand the theory.Underlying all is the notion of radioactivity.It consists in the fact that the nuclei of certain atoms inherent instability.This means that they disintegrate spontaneously and this generates an ionizing radiation, i.e. radiation.It is formed by several kinds of particles: alpha, beta, gamma, and neutron.Especially dangerous is the gamma radiation, which is characterized by a high penetrating power.X-rays similar to gamma rays, but has a lower energy.The largest natural source of such radiation - the sun.But it is only part of the radiation of all, of what constitutes the norm of background radiation.
components foniruyuschego radiation
It is composed of natural and man-made elements.Natural radiation is produced from such factors:
- cosmic rays;
- underground deposits of radionuclides, they are also irradiated with natural building materials, which later built the house;
- same radioactive substance, but dispersed in water and air;
- as well as in food;
- potassium-rubidium-40 and 87, which in humans are always present and they can not be disposed of.
natural radioactive background is always and everywhere.This is not the exception but the rule.It differs only in the rate of background radiation for each specific area.
artificially increasing background radiation by human activities.For example, mining, incineration, application of phosphate fertilizers.Not smaller contribution falls to test nuclear weapons, nuclear power plants and aircraft.Moreover, one can not discount the occasional infection.This is all possible accidents and transportation losses.
The problem is that a person has no sense organ, which could perceive radiation.Therefore, in hazardous areas is required to use special devices - dosimeters, which will signal about exceeding the received radiation.
Units radiation and radioactivity
These are different concepts and their measurement units are different.Measure radioactivity - this active substance.It is measured in becquerels.One becquerel is equal to one disintegration per second atom.Often it is assessed per unit mass or volume.
ionizing radiation that occurs during the decay of atoms, measured in X-rays.But this is a very large value.Therefore, in practice, often referred microroentgens, ie a millionth part.Moreover, the impact depends on the irradiation time.And the value, which is measured by the rate of background radiation - mR / h, that is, micro-roentgen per hour.
There is one value - is the sievert.It is used to evaluate the effect on humans.With this measure unit dose equivalent.The power of this dose was named sievert per hour.In domestic purposes one sievert is equal to 100 X-rays.
Examples of dose values
All radiation, which is produced by the body, the radiation leaves the track, and get rid of it will never be possible.Thus, all natural sources of radiation add up to a dose that is around the value of 3 mSv per year.It may be a little less or a little more depending on the terrain.But she characterized as allowable rate of background radiation.
same dose received by man in his life should not be more than 700 mSv.The most common approach to this value of mountain communities.
In addition, people are constantly faced with the additional exposure, such as a medical examination.It is desirable that these studies do not exceed the maximum dose.
| value | Title procedures |
| to 0.06 mSv | digital fluorogram |
| to 0.25 mSv | fluorogramon film |
| to 0.4 mSv | radiography |
| to 0.35 mSv | x-ray of the tooth |
| about 0.001 mSv | scanner at the airport |
What causes the effects of radiation onhuman organism?
If a dose is placed in the values that regulate the rate of background radiation, people simply do not notice.Their life goes on, and no adverse effects are not evident.However, if the dose is many times the value and exposure occurs over a short period of time, the question of radiation sickness.It causes metabolic disorders, leukemia and cancer, radiation skin burns and cataracts, complicates the course of infectious diseases, leading to infertility.
methods of radiation protection
They are three:
- time, since over the years the radiation dose is reduced;
- distance because the distance from the radiation source intensity is reduced;
- matter because it absorbs gamma rays.
