“The Enhanced Fujita scale (abbreviated as EF-Scale) rates tornado intensity based on the severity of the damage they cause. It is used in some countries, including the United States, Canada, China, and Mongolia.
“The Enhanced Fujita scale replaced the decommissioned Fujita scale that was introduced in 1971 by Ted Fujita.[1] Operational use began in the United States on February 1, 2007, followed by Canada on April 1, 2013.[2][3][4]
“It has also been proposed for use in France.[5][needs update]
“The scale has the same basic design as the original Fujita scale—six intensity categories from zero to five, representing increasing degrees of damage.
“It was revised to reflect better examinations of tornado damage surveys, in order to align wind speeds more closely with associated storm damage.”
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