Specific activity Specific activity Specific activity is the activity per quantity of a radionuclide and is a physical property of that radionuclide. Activity is a quantity related to radioactivity. The SI unit of activity is the becquerel (Bq), equal to one reciprocal second. The becquerel is defined as the number of radioactive transformations per second that occur in a particular radioactive isotope. Its related non-SI unit equivalent is the Curie (Ci) which is transformations per second. Since the probability of radioactive decay for a given radionuclide is a fixed physical quantity (with some slight exceptions, see changing decay rates), the number of
Comparison of Chernobyl and other radioactivity releases to the inverse square law the dose suffered by members of the general public tends to be very small. Also, very little environmental contamination normally occurs as a result of these accidents. For instance, at Sarov the radioactivity remained confined to within the actinide metal objects which were part of the experimental system, according to the IAEA report (2001). Even the SL-1 accident (meltdown of experimental nuclear reactor in Idaho, 1961) failed to release much radioactivity outside the building in which it occurred. Comparison of Chernobyl and other radioactivity releases This article compares the radioactivity release and decay from the