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Formula quantity
Strategic Special nuclear material, in any combination, in a quantity of 5000 grams or more computed by the formula, grams = (grams contained U-235) + 2.5 (grams U-233 + grams plutonium). This class of material is sometimes referred to as a Category I quantity of material (see 10 CFR 70.4).
Page Last Reviewed/Updated Thursday, August 27, 2026
Page Last Reviewed/Updated Thursday, August 27, 2026