Radiation Absorbed Dose (Rad)
The rad is a unit used to measure absorbed radiation dose. This relates to the amount of energy actually absorbed in some material, and is used for any type of radiation and any material. One rad is defined as the absorption of 100 ergs per gram of material. The unit rad can be used for any type of radiation, but it does not't describe the biological effects of the different radiations.
Common unit of radiation dose equal to 1000 rads, 10 grays, or 10 joules of energy per kilogram of mass.