Search results
Results From The WOW.Com Content Network
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 ).
Absorbed dose is a dose quantity which is the measure of the energy deposited in matter by ionizing radiation per unit mass. Absorbed dose is used in the calculation of dose uptake in living tissue in both radiation protection (reduction of harmful effects), and radiology (potential beneficial effects, for example in cancer treatment).
The definition of the BRET unit is apparently unstandardized, and depends on what value is used for the average annual background radiation dose, which varies greatly across time and location. The 2000 UNSCEAR estimate for worldwide average natural background radiation dose is 2.4 mSv (240 mrem), with a range from 1 to 13 mSv. A small area in ...
Committed equivalent dose, H T (t) is the time integral of the equivalent dose rate in a particular tissue or organ that will be received by an individual following intake of radioactive material into the body by a Reference Person, where s is the integration time in years. [13]
Consider the sunburn, a deterministic effect: [4] when exposed to bright sunlight for only ten minutes [5] at a high UV Index, that is to say a high average dose rate, [6] the skin can turn red and painful. The same total amount of energy from indirect sunlight spread out over several years - a low average dose rate - would not cause a sunburn ...
These are worn as badges but can give an indication of instantaneous dose rate and an audible and visual alarm if a dose rate or a total integrated dose is exceeded. A good deal of information can be made immediately available to the wearer of the recorded dose and current dose rate via a local display.
Count rate measurements are associated with the detection of particles, such as alpha particles and beta particles. However, for gamma ray and X-ray dose measurements a unit such as the sievert is normally used. Both cpm and cps are the rate of detection events registered by the measuring instrument, not the rate of emission from the source of ...
Recognized effects of higher acute radiation doses are described in more detail in the article on radiation poisoning.Although the International System of Units (SI) defines the sievert (Sv) as the unit of radiation dose equivalent, chronic radiation levels and standards are still often given in units of millirems (mrem), where 1 mrem equals 1/1,000 of a rem and 1 rem equals 0.01 Sv.