Roentgen 07
Roentgen 07 : Former unit of ?ion dose, symbol: R. The ion dose of 1 roentgen is equal to the generation of an electrostatic charge unit by gamma or x-radiation in 1 cm3 dry air under normal conditions (1.293 mg air) The new unit of the ion dose is coulomb divided by kilogram (C/kg). 1 R = 258 ?C/kg; 1 C/kg _ 3 876 R