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The human body contains many types of cells, and the human can be killed by the loss of a single type of cell in a vital organ. For many short-term radiation deaths due to what is commonly known as radiation sickness (3 to 30 days after exposure), it is the loss of bone marrow cells (which produce blood cells ), and the loss of other cells in ...
These are effects that are certain to happen, as opposed to the uncertain effects of low levels of radiation that have a probability of causing damage. A whole-body acute exposure to 5 grays or more of high-energy radiation usually leads to death within 14 days. LD 1 is 2.5 Gy, LD 50 is 5 Gy and LD 99 is 8 Gy. [10]
Radiation exposure is a measure of the ionization of air due to ionizing radiation from photons. [1] It is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air. [ 1 ]
In the 1930s the roentgen was the most commonly used unit of radiation exposure. This unit is obsolete and no longer clearly defined. This unit is obsolete and no longer clearly defined. One roentgen deposits 0.877 rad in dry air, 0.96 rad in soft tissue, [ 9 ] or anywhere from 1 to more than 4 rad in bone depending on the beam energy. [ 10 ]
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.
The absorbed dose is equal to the radiation exposure (ions or C/kg) of the radiation beam multiplied by the ionization energy of the medium to be ionized. For example, the ionization energy of dry air at 20 °C and 101.325 kPa of pressure is 33.97 ± 0.05 J/C .
EMF stands for electric and magnetic fields, which, according to the National Institute of Environmental Health and Sciences, are invisible areas of energy often referred to as radiation.
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. The radiation weighting factor for neutrons has been revised over time and remains controversial. This may seem to be a paradox.