EF1 may refer to:
*
EF1 item allocation - a rule for fair allocation of indivisible objects among people with different preferences.
* A tornado intensity rating on the
Enhanced Fujita scale
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 repl ...
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