| Unit | Symbol | Brief Description | Use |
|---|---|---|---|
| Curie | Ci | 3.7 x 1010 disintegrations per second (2.22 x 1012 DPM) | Special unit of activity |
| Becquerel | Bq | 1 disintegration per second | SI unit of activity |
| Roentgen | R | 2.58 x 10-4 C/kg. (photons in air) | Special unit of exposure; applies only to gamma and x radiation |
| Rad | rad | 0.01 J/kg (100 ergs/g) | Special dose unit; applies to any radiation |
| Gray | Gy | 1 J/kg. | SI unit of dose (Equals 100 rads) |
| Dose Equivalent | H | Dose x Q x any other modifying factors | Radiation protection |
| Quality Factor | Q | Biological effectiveness related to type of radiation | Radiation protection |
| Rem | rem | Rad dose x Q x any other modifying factors | Special unit of human dose equivalent |
| Sievert | Sv | Gy x Q x any other modifying factors | SI unit of human dose equivalent (Equals 100 rem) |
| Activity: | 1 Ci = 3.7 x 1010 Bq = 2.22 x 1012 DPM | ||
| Exposure: | 1 R = 2.58 x 10-4 C/kg. | ||
| The special unit for exposure is the Roentgen. There is no SI unit for exposure; it is simply expressed in C/kg. | |||
| Dose: | 100 rads = 1 Gy | ||
| Dose Equivalent: | 100 rems = 1 Sv | ||
| KeV: | Kilo (1000) electron volts | ||
| MeV: | Mega (1,000,000) electron volts | ||
| 1 MeV = 1000 keV | |||
| 1 KeV = .001 MeV | |||
| 1 Ci = 3.7 x 1010 Bq = 37 GBq | |||
| 27 uCi = 1 x 106 Bq = 1 MBq | |||
| 1 rad = 0.01 Gy = 10 mGy | |||
| 1 rem = 0.01 Sv = 10 mSv | |||
File: radunits.html
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