Background radiation
Sources of radiation Natural background radiation is due to radiation of natural radionuclides of the Earth and cosmic radiation. Technologically modified natural background radiation is formed from natural sources of ionizing radiation, for example radiation scattered in the environment of natural radionuclides. Artificial background radiation - the global pollution of the environment by artificial radionuclides formed in the fission of nuclei of uranium and plutonium. This background is due to testing of nuclear weapons, in part by emissions from nuclear power plants noble gases, carbon, and tritium. Artificial background radiation in the globe on average is 1 -3% of natural background radiation.
Units of radiation measurement measuring object Unit Description Absorbed dose ionizing radiation Gy Absorbed dose is a physical dose quantity D representing the mean energy imparted to matter per unit mass by ionizing radiation. In the SI system of units, the unit of measure is joules per kilogram, and its special name is gray (Gy). rad The rad is a deprecated unit of absorbed radiation dose, defined as 1 rad = 0. 01 Gy = 0. 01 J/kg. It was originally defined in CGS units in 1953 as the dose causing 100 ergs of energy to be absorbed by one gram of matter R Radiation exposure is a measure of the ionization of air due to ionizing radiation from photons; that is, gamma rays and X-rays. It is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air. Exposure dose of radiation The SI unit of exposure is the coulomb per kilogram (C/kg), which has largely replaced the roentgen (R). One 1 roentgen equals 0. 000258 C/kg; an exposure of one coulomb per kilogram is equivalent to 3876 roentgens. Effective (equivalent) dose of ionizing radiation REM 1 REM corresponds to irradiation of a living organism the type of radiation in which there is the same biological effect as exposure dose of gamma radiation in 1 R Cv Equivalent dose is a dose quantity H representing the stochastic health effects of low levels of ionizing radiation on the human body. It is derived from the physical quantity absorbed dose, but also takes into account the biological effectiveness of the radiation, which is dependent on the radiation type and energy. In the SI system of units, the unit of measure is the sievert (Sv).
Radiation accident Violation of the rules of safe operation of nuclear power installations, equipment or device, in which there has been a release of radioactive products or ionizing radiation provided by the project limits for their safe operation, leading to exposure of the population and environmental pollution. nuclear power plant; enterprise for nuclear fuel production, reprocessing and disposal of nuclear waste; research and other companies with nuclear installations and stands; nuclear transport power systems (including space vehicles); military facilities.
International Nuclear Event Scale The International Nuclear and Radiological Event Scale (INES) was introduced in 1990 by the International Atomic Energy Agency (IAEA) in order to enable prompt communication of safetysignificant information in case of nuclear accidents. The scale is intended to be logarithmic, similar to the moment magnitude scale that is used to describe the comparative magnitude of earthquakes. Each increasing level represents an accident approximately ten times more severe than the previous level. Compared to earthquakes, where the event intensity can be quantitatively evaluated, the level of severity of a man-made disaster, such as a nuclear accident, is more subject to interpretation. Because of the difficulty of interpreting, the INES level of an incident is assigned well after the incident occurs. Therefore, the scale has a very limited ability to assist in disaster-aid deployment. As INES ratings are not assigned by a central body, high-profile nuclear incidents are sometimes assigned INES ratings by the operator, by the formal body of the country, but also by scientific institutes, international authorities or other experts which may lead to confusion as to the actual severity. A number of criteria and indicators are defined to assure coherent reporting of nuclear events by different official authorities. There are seven nonzero levels on the INES scale: three incident-levels and four accident-levels. There is also a level 0.
International Nuclear Event Scale Level appellation Criterion 7 Major accident Major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures 6 Serious accident Significant release of radioactive material likely to require implementation of planned countermeasures 5 Accident with wider consequences Release of large quantities of radioactive material within an installation with a high probability of significant public exposure. This could arise from a major criticality accident or fire. 4 Accident with local consequences Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure. 3 Serious incident Exposure in excess of ten times the statutory annual limit for workers. 2 Incident Radiation levels in an operating area of more than 50 m. Sv/h. 1 Anomaly There is a deviation from the permitted scope of operation of the reactor 0 Deviation No safety significance
Zone of radioactive contamination C D B A A – area of moderate infection B – the zone of strong contamination C – the zone of dangerous infection D – zone is extremely dangerous infection Параметры D C B А The radiation dose during a complete collapse of the fallen in the zone of radioactive materials (R) 4000 -10000 1200 -4000 400 -1200 40 -400 The radiation level at the boundary with the next zone after 1 hour 800 240 80 8
BACKGROUND RADIATION IN THE WORLD Guarapari Brasil ~ 160
Medical application Treatment with radioactive sand at the Brazilian resort of Guarapari Radon baths at the Spa town Jáchymov in the Czech Republic
Total dose of irradiation of population
Natural anomalies
The radiation background in Russia Среднее значение по стране 0, 95
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