Ionizing radiation Roentgen equivalent

Rep—Roentgen equivalent, physical A former unit of ionizing radiation equivalent to the dosage of 93 ergs absorbed per gram of tissue (93 erg/gm=0.93 rad). 

Roentgen equivalent man (rem) The amount of ionizing radiation of any type that produces the same damage to humans as 1 roentgen of radiation. One rem = 1 roentgen equivalent physical (rep)/relative biological effectiveness (RBE). In the latest nomenclature, 100 rem = 1 Sievert (Sv). 

Roentgen equivalent physical (rep) One rep is equivalent to the amount of ionizing radiation of any type that results in the absorption of energy of 93 ergs/g, and is approximately equal to 1 roentgen of X-radiation in soft tissue. 

Rem (acronym for roentgen-equivalent man) The unit of dose of ionizing radiation that produces the same biological effect as a unit of absorbed dose of ordinary x-rays. 

REM (rem). A unit of dose equivalent in the field of radiation dosimetry. One rem equals the amount of ionizing radiation of any type which produces the same damage to humans as 1 roentgen of approximately 200 kilovolts x-radiation. (The unit is abbreviation of Roentgen Equivalent Man.)... 

Different kinds of radiation have different ionization efficiencies and are absorbed in different ways. In order to compensate for this the unit rem ( roentgen equivalent, man ) was introduced. It is defined as the quantity of radiation of any type which produces the same biological effect in man as that produced by 1 r of X-ray or y ray radiation. However, the biological effect depends upon the part of the body irradiated and on the type of radiation. This problem is dealt with by estimating a relative biological effectiveness (RBB), in relation to y-rays, for various parts of the body. For example, as far as the production of cataracts is concerned, 1 rad of fast neutrons is ten times as effective as 1 rad of y-rays. Thus if the eyes were... 

The standard unit for measuring the quantity of ionizing radiation is the roentgen (R). The roentgen is defined as a radiation flux that will produce 2.08 x 10 ion pairs per 0.001293 g (i.e., 1 cm ) of dry air at standard temperature and pressure. This number of ion pairs is equivalent to an energy of 84 erg. 

For evaluation of the risk of exposure to ionizing radiation in humans, the dose equivalent in rem (roentgen equivalent man) is defined as... 

REM is the dosage of any ionizing radiation that will cause biological injury to human tissue equal to the injury caused by one roentgen of x-ray or gamma ray dosage with 1 rem is equivalent to 0.01 Sievert (Sv). 

Rem—Roentgen equivalent man, the nnit of dose of any ionizing radiation that produces the same biological effect on human tissne as one roentgen of x-rays. 

REM (Roentgen Equivalent Man) - Is defined as the amount of any type of ionizing radiation that produces the same damage to man as 1 roentgen of about 200kV radiation. The quantity of such biological units is named dose equivalent. 

Rem means a measure of the dose of any ionizing radiation to body tissue in terms of its estimated biological effect relative to a dose of 1 roentgen (r) of X-rays (1 millirem (mrem)=0.001 rem). The relation of the rem to other dose units depends upon the biological effect under consideration and upon the conditions for irradiation. Each of the following is considered to be equivalent to a dose of 1 rem ... 

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. 

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