The new special names of SI units in the field of ionizing radiations.
At its meeting in May-June 1975, the 15th Conference Generale des Poids et Mesures adopted two new special names of SI units; the becquerel, symbol Bq, equal to the second to the power minus one, s-1, for the quantity activity, and the gray, symbol Gy, equal to the joule per kilogram, J-kg-1, for absorbed dose and related quantities in the field of ionizing radiations. This action was preceded by a recommendation of the International Commission on Radiation Units and Measurements (ICRU) in 1974.
D007390:International Agencies; D011829:Radiation Dosage / Q000592:standards; D011839:Radiation, Ionizing / Q000592:standards*; D011874:Radiometry / Q000592:standards*; D014894:Weights and Measures