Regulations last checked for updates: May 15, 2026

Title 10 - Energy last revised: Apr 29, 2026
§ 53.240 - Licensing-basis events.

(a) Licensing-basis events must be identified for each commercial nuclear plant and analyzed under § 53.450 to demonstrate that the safety requirements in this subpart have been satisfied.

(b) The identified LBEs, ranging from anticipated event sequences to very unlikely event sequences, must collectively address appropriate risk-informed combinations of malfunctions of plant SSCs, human errors, facility hazards, and the effects of external hazards.

(c) The analysis of LBEs must—

(1) Include analysis of one or more DBAs under § 53.450(f);

(2) Confirm the adequacy of design features and programmatic controls needed to satisfy the safety criteria defined in §§ 53.210 and 53.220, and

(3) Establish related functional requirements for plant SSCs, personnel, and programs.

authority: Atomic Energy Act of 1954, secs. 11, 101, 103, 108, 122, 147, 161, 181, 182, 183, 184, 185, 186, 187, 189, 223, 234 (42 U.S.C. 2014,2131,2132,2133,2134,2135,2138,2152,2167,2169,2201,2231,2232,2233,2234,2235,2236,2237,2239,2273,2282; Energy Reorganization Act of 1974, secs. 201, 202, 206, 211 (42 U.S.C. 5841,5842,5846,5851; Nuclear Waste Policy Act of 1982, sec. 306 (42 U.S.C. 10226); National Environmental Policy Act of 1969 (42 U.S.C. 4332); 44 U.S.C. 3504 note; Pub. L. 115-439, 132 Stat. 5571
source: 91 FR 15794, Mar. 30, 2026, unless otherwise noted.
cite as: 10 CFR 53.240