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Rad Prot
Rad Prot Chapter 3
Question | Answer |
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absorbed dose (D) | The deposition of energy per unit mass by ionizing radiation in the patient’s body tissue. |
absorbed dose (D) | This absorbed energy is responsible for whatever biologic damage occurs as a result of tissues being exposed to x-radiation. |
absorbed dose (D) | The gray (Gy) is the SI unit of this radiation quantity. |
collective effective dose (ColEfD) | Term used to describe radiation exposure of a population or group from low doses of different sources of ionizing radiation. |
coulomb (C) | SI unit of electric charge equal to 1 ampere-second (the quantity of electric charge transferred across unit area by a current of 1 ampere in 1 second). |
coulomb per kilogram (C/kg) | SI unit of radiation exposure: 1 coulomb per kilogram (C/kg) of air equals 1 SI unit of exposure, or 1/(2.58 x 10-⁴) R |
effective dose (EfD) | A quantity that is used for radiation protection purposes to provide a measure of the overall risk of exposure to ionizing radiation. |
Effective dose (EfD) | takes into account the dose for all types of ionizing radiation to organs or tissues in the human body being irradiated and the overall harm, or weighting factor, of those biologic components for developing a radiation-induced cancer. |
equivalent dose (EqD) | A quantity used for radiation protection purposes that attempts to take into account the variation in biologic harm that is produced by different types of radiation. |
equivalent dose (EqD) | is the product of the average absorbed dose in a tissue or organ in the human body and its associated radiation weighting factor chosen for the type of radiation in question. |
equivalent dose (EqD) | enables the calculation of the effective (EfD) dose. |
exposure (X) | The total electrical charge per unit mass that x-ray and gamma ray photons with energies up to 3 MeV generate in air only. |
exposure (X) | the amount of ionizing radiation that may strike an object, such as the human body when in the vicinity of a radiation source. |
exposure (X) | Measured in coulombs per kilogram (C/kg) or roentgens (R). |
genetic, or heritable, effects | Biologic effects of ionizing radiation or other agents on generations yet unborn. |
gray (Gy) | SI unit of absorbed dose. An energy absorption of 1 joule (J) per kilogram (kg) of matter in the irradiated object. |
International System of Units (SI) | System of units that allows an interchange of units among all branches of science throughout the world. |
linear energy transfer (LET) | The amount of energy transferred on average by incident radiation to an object per unit length of track through the object. |
linear energy transfer (LET) | It is expressed in units of keV/µm. |
long-term, or late, somatic effects | Effects of ionizing radiation that appeared months or years following exposure to ionizing radiation. |
occupational exposure | Radiation exposure received by radiation workers in the course of exercising their professional responsibilities. |
rad | The unit that indicates the amount of radiant energy transferred to an irradiated object by any type of ionizing radiation. |
rad | is equivalent to an energy transfer of 100 erg per gram of irradiated object and 1/100 gray. |
radiation weighting factor (W ) | A dimensionless factor (a multiplier) used for radiation protection purposes to account for differences in biologic impact between various types of ionizing radiations. |
radiation weighting factor (W ) | This factor places risks associated with biologic effects on a common scale. |
rem | Traditional unit for the radiation quantity currently in use (equivalent dose [EqD]). |
rem | defined as the dose that is equivalent to any type of ionizing radiation that produces the same biologic effect as 1 rad of x-radiation. |
roentgen (R) | Internationally accepted unit of measurement of exposure to x-radiation and gamma radiation. |
roentgen (R) | One of these is the photon exposure that produces under standard conditions of pressure and temperature a total positive or negative ion charge of 2.58 x 10-⁴ coulombs per kilogram of dry air. |
short-term somatic effects (acute or early effects) | Somatic effects that appear within minutes, hours, days, or weeks of the time of radiation exposure. |
sievert (Sv) | The SI unit of measure for the radiation quantity of equivalent dose (EqD). |
sievert (Sv) | one of these equals 1 joule of energy absorbed per kilogram of tissue (for x-radiation, Q |
sievert (Sv) | This unit is used only for radiation protection purposes. |
sievert (Sv) | It provides a common scale whereby varying degrees of biologic damage caused by equal absorbed doses of different types of ionizing radiation can be compared with the degree of biologic damage caused by the same amount of x-radiation or gamma radiation. |
somatic damage | Biologic damage to the body of the exposed individual. |
tissue weighting factor (W ) | A value denoting the percentage of the summed stochastic (cancer plus genetic) risk stemming from irradiation of tissue (T) to the all-inclusive risk, in which the entire body is irradiated in a uniform fashion. |
tissue weighting factor (W ) | This factor assigns risk for potential biologic responses from various types of ionizing radiation on a common scale and takes into account the relative detriment to each organ and tissue. |
traditional units | Special units associated with radiation protection and dosimetry, namely, the roentgen and the rem. |