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In diagnostic radiology, the F-factor is the conversion factor between exposure to ionizing radiation and the absorbed dose from that radiation. In other words, it converts between the amount of ionization in air (roentgens or, in SI units, coulombs per kilogram of absorber material) and the absorbed dose in air (rads or grays).
The embryo and fetus are considered highly sensitive to radiation exposure. [8] Complications from radiation exposure include malformation of internal organs, reduction of IQ, and cancer formation. [8] The SI unit of exposure is the coulomb per kilogram (C/kg), which has largely replaced the roentgen (R). [9]
In the "1951 Recommendations" the commission recommended a maximum permissible dose of 0.5 roentgen (0.0044 grays) in any 1 week in the case of whole-body exposure to X and gamma radiation at the surface, and 1.5 roentgen (0.013 grays) in any 1 week in the case of exposure of hands and forearms. [1]
Exposure can be from a source of radiation external to the human body or due to internal irradiation caused by the ingestion of radioactive contamination. Ionizing radiation is widely used in industry and medicine, and can present a significant health hazard by causing microscopic damage to living tissue.
CDE is defined by the United States Nuclear Regulatory Commission in Title 10, Section 20.1003, of the Code of Federal Regulations (10 CFR 20.1003), such that "The Committed dose equivalent, CDE (H T,50) is the dose to some specific organ or tissue of reference (T) that will be received from an intake of radioactive material by an individual during the 50-year period following the intake".
W R is the radiation weighting factor defined by regulation. Thus for example, an absorbed dose of 1 Gy by alpha particles will lead to an equivalent dose of 20 Sv, and an equivalent dose of radiation is estimated to have the same biological effect as an equal amount of absorbed dose of gamma rays, which is given a weighting factor of 1.
Stochastic in this context is defined as the probability of cancer induction and genetic damage, due to low levels of radiation. The SI unit of measure is the sievert . A committed dose from an internal source represents the same effective risk as the same amount of effective dose applied uniformly to the whole body from an external source, or ...
In radiometry, radiant exposure or fluence is the radiant energy received by a surface per unit area, or equivalently the irradiance of a surface, integrated over time of irradiation, and spectral exposure is the radiant exposure per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength.