Ionizing Radiation absorbed dose

Absorbed dose Mean value of energy of the ionizing radiation absorbed by the unit of mass of the processed material. The unit of absorbed dose is 1 Gray (Gy) = 1 J kg or 1 kGy = ljg. The older unit, used officially until 1986 and still used occasionally in literature, is 1 megarad (Mrad), which is equivalent to 10 kGy. 

Rad (acronym for radiation-absorbed dose) The original basic unit of absorbed dose of ionizing radiation one rad equals 100 ergs of radiation energy per gram of absorbing material. This unit has been replaced by the gray (Gy). 

RAD radiation absorbed dose (a unit of absorbed dose of ionizing radiation)... 

Radiation absorbed dose (rad) l(X)ergs/g (energy imparted to a unit mass of matter by ionizing radiation) 0.87 rad = r... 

Curie = A physical amount of radioactive material 1 Megacurie (MCI) = 1,000,000 Curies 1 Kilocurie (kCi) = 1,000 Curies 1 Millicurie (mCi) = 0.0001 Curies 1 Microcurie (uCi) = 0.000001 Curies Roentgen = Ionization per cm of dry air RAD = Radiation absorbed dose — Dosage REM = Biological effects... 

While a curie is a measure of the physical amount, the roentgen is a measure of the amount of ionization produced by a specific material. It is the amount of x-ray or gamma radiation that produces 2 billion ionizations in 1 cm of dry air. A RAD is the radiation-absorbed dose (roughly equal to a roentgen). The radiation equivalent man (REM), also roughly equal to a roentgen, is a term for how much radiation has been absorbed, or the biological effect of the dose. 

Dose means the quantity of ionizing radiation absorbed, per unit of mass, by the body or by any portion of the body. 

Rad rad [radiation absorbed dose] (1918) (1) Adep-recated, but still widely used, unit of energy absorbed by a material, including living matter, from exposure to ionizing radiation. 1 rad = 0.01 gray (Gy) = 0.01 J/kg. 

Effect of Radiation on Matter—The ionizing power of radiation (Fig. 25-10) is the basis both of radiation s effects on matter and methods used to detect radiation. Radiation detectors include simple film badges, Geiger-Miiller (G-M) counters for routine measurements (Fig. 25-11), and scintillation counters in biomedical studies. Two units of measure are used to quantify exposure to radioactivity. One—the rad (radiation absorbed dose)— is related to the amount of radiation energy absorbed, while the other—the rem (radiation equivalent for man)—takes into account the differing effects of the various types of radiation (Table 25.5). 

Absorbed Dose, Radiation—The mean energy imparted to the irradiated medium, per unit mass, by ionizing radiation. Units rad (rad), gray (Gy). 

Absorbed Dose—The energy imparted to matter by ionizing radiation per unit mass of irradiated material at the place of interest. The unit of absorbed dose is the rad. One rad equals 100 ergs per gram. In SI units, the absorbed dose is the gray which is 1 J/kg (see Rad). 

Quality Factor (Q)—The linear-energy-transfer-dependent factor by which absorbed doses are multiplied to obtain (for radiation protection purposes) a quantity that expresses - on a common scale for all ionizing radiation - the approximate biological effectiveness of the absorbed dose. 

Relative Biological Effectiveness (RBE)—The RBE is a factor used to compare the biological effectiveness of absorbed radiation doses (i.e., rad) due to different types of ionizing radiation. More specifically, it is the experimentally determined ratio of an absorbed dose of a radiation in question to the absorbed dose of a reference radiation (typically 60Co gamma rays or 200 keV x rays) required to produce an identical biological effect in a particular experimental organism or tissue (see Quality Factor). 

Dose equivalent or rem is a special radiation protection quantity that is used, for administrative and radiation safety purposes only, to express the absorbed dose in a manner which considers the difference in biological effectiveness of various kinds of ionizing radiation. The ICRU has defined the dose equivalent, H, as the product of the absorbed dose, D, and the quality factor, Q, at the point of interest in biological tissue. This relationship is expressed as H = D x Q. The dose equivalent concept is applicable only to doses that are not great enough to produce biomedical effects. 

Nonaqueous liquids, semi-solids, and dry powders dry heat at 160°C/120 minutes then dry heat under alternative conditions of time and temperature to achieve a sterility assurance level of 10 6 then an alternative to dry heat, e.g., ionizing radiation with a minimum absorbed dose of not less than 25 kGy then a validated alternative irradiation dose (according to ISO 11137) then aseptic filtration and aseptic processing and then the use of presterilized components and aseptic compounding or filling... 

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