The Medvedev–Sponheuer–Karnik scale, also known as the MSK or MSK-64, is a macroseismic intensity scale used to evaluate the severity of ground shaking on the basis of observed effects in an area where an earthquake transpires.
The scale was first proposed by Sergei Medvedev (USSR), Wilhelm Sponheuer (East Germany), and Vít Kárník (Czechoslovakia) in 1964.
[1] With minor modifications in the mid-1970s and early 1980s, the MSK scale became widely used in Europe and the USSR.
MSK-64 is still being used in India, Israel, Russia, and throughout the Commonwealth of Independent States.
The MSK scale has 12 intensity degrees expressed in Roman numerals (to prevent the use of decimals):