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Based on the formula of the ratio of the average maximum wind speed in 〖WTBX〗t〖WTBZ〗 seconds to the average maximum wind speed in one hour in the Minimum Design Load for Buildings and Other Structures of the United States, this paper deduces the conversion method between the wind speed measurement standards of EF level and F level, and converts 22 tornado cases in the BeijingTianjinHebei region from 1956 to 2016 from EF level to F level, and then according to the related guidelines for nuclear power plants and the tornado risk assessment method recommended in the Extreme Meteorological Events for Site Selection (HAD101/10), the risk degree of tornado in BeijingTianjinHebei region is quantitatively evaluated. The main conclusions are as follows: for 1/4 mile wind run, the average maximum wind speed of 122 tornado cases in BeijingTianjinHebei is lower than 3second average maximum wind speed, 2.1 m s1 lower than the average, and the higher the wind speed is, the smaller the gap is; 122 tornado cases are distributed in four grades from F0 to F3, including 31 in F0, 78 in F1, 12 in F2 and 1 in F3; in the BeijingTianjinHebei region, tornadoes occur most frequently are in Tianjin, Tangshan and Zhangjiakou, 21, 21 and 14 times, respectively, and the most severe tornadoes occur in Langfang (3); there were no strong tornadoes in Hengshui, Chengde, Baoding and Beijing; the recurrence periods of tornadoes exceeding EF1, EF2, EF3 and EF4 levels in Beijing, Tianjin and Hebei are 5.8, 10.1, 20.2 and 49.5 years respectively, and those exceeding F1, F2, F3 and F4 levels are 4.9, 13.8, 38.5 and 130.7 years, respectively; the recurrence periods of tornadoes exceeding F1, F2, F3 and F4 levels are 4.9, 13.8, 38.5 and 130.7 years; in the BeijingTianjinHebei region, the tornado design reference wind speed on the unit surface (1 km2) corresponding to the 107 probability level is 73.4 m s-1。