Charles Francis Richter (April 26, 1900 - September 30, 1985) was an American seismologist and physicist. He was educated at Stanford University, California. He started his PhD at Caltech, California, and later spent most of his career there (from 1937 onwards). Richter is most famous as the creator of the Richter magnitude scale which, until the development of the moment magnitude scale in 1979, quantified the size of earthquakes. Inspired by Kiyoo Wadati's 1928 paper on shallow and deep earthquakes, Richter first used the scale in 1935 after developing it in collaboration with Beno Gutenberg; both worked at California Institute of Technology. The scale measures the magnitude of an earthquake, ranging from 1-9. An increase of one unit equates to a 30-fold increase in earthquake energy. In the 1960s he became involved in earthquake engineering through development of building codes for earthquake prone areas. The city government of Los Angeles removed many ornaments and cornices from municipal buildings in the 1960s as a result of Richter's awareness campaigns. After the 1971 San Fernando earthquake, the city cited Richter's warnings as important in preventing many deaths. Richter retired in 1970. He was also a naturist, and travelled to many nudist communities with his wife. He died of congestive heart failure in 1985 at the age of 85.