The introduction of SI units into the radiological sciences

Although the concept of a unified International System of Units is to be applauded, the rigidity of its application is less welcome. The new unit of activity, the becquerel, lacks convenience since it is at least a million times too small. A modest tracer dose will already be in the mega range; a therapeutic dose of radioiodine will be expressed in gigabq. and a large cobalt unit will have a source whose activity is in hundreds of terabq. The introduction of SI units into the radiological sciences is not therefore likely to be greeted with any great enthusiasm. (U.K.)