History of the metric system levels of the krypton 86 atom as the new standard for the metre. The standard metre artefact was retired. In 1960, Giorgi's proposals were adopted as the basis of the "Système International d'Unités" (International System of Units), the SI. This initial definition of the SI included six base units, the metre, kilogram, second, ampere, degree Kelvin and candela, and sixteen coherent derived units. The evolution of the SI after its publication in 1960 has seen the addition of a seventh base unit, the "mole", and six more derived units, the "pascal" for pressure, the "gray", "sievert" and "becquerel" for radiation,
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