Also known as Radiation Absorbed Dose
non-SI unit measuring absorbed dose of ionizing radiation
Key facts
- Unit system
- CGS units
- Unit of
- Absorbed dose of ionizing radiation
- Symbol
- rad
- Si derived units
- 0.01 J ⋅ kg
- Si units
- 0.01 Gy
- Cgs
- 100 erg /g
via Wikipedia infobox
Wikidata facts
Show 3 more facts
- unit symbol
- rad
- Wikidata SPARQL query equivalent
- wd:Q1052397 p:P2370/psn:P2370 [wikibase:quantityAmount ?source; wikibase:quantityUnit ?base]. ?item p:P2370/psn:P2370 [wikibase:quantityAmount ?target; wikibase:quantityUnit ?base]. BIND(?source / ?target as ?value)
- conversion to SI unit
- 0.01
Sources (1)
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Article
Relation between some ionizing radiation units The rad is a unit of absorbed radiation dose, defined as 1 rad = 0.01 Gy = 0.01 J/kg. It was originally defined in CGS units in 1953 as the dose causing 100 ergs of energy to be absorbed by one gram of matter. The material absorbing the radiation can be human tissue, air, water, or any other substance.
It has been replaced by the gray (symbol Gy) in SI derived units. The rad is still used in the United States, although this is "strongly discouraged" in Chapter 5.2 of the Guide to the SI, which was written and published by the U.S. National Institute of Standards and Technology. However, the numerically equivalent SI unit submultiple, the centigray (symbol cGy), is widely used to report absorbed doses within radiotherapy. The roentgen, used to quantify the radiation exposure, may be related to the corresponding absorbed dose by use of the F-factor.