Information concerning inertial confinement fusion which reveals or isĮight (8) additional subcategories of Sigma 11 not included in this list are Weapons or weapon systems, e.g., reliability studies, fuzing studies, damageĬhemistry, metallurgy, and processing of materials peculiar to the field ofĪtomic weapons or nuclear explosive devices. General studies not directly related to the design or performance of specific Transportation and nuclear explosive operations that significantly enhancesĪn adversary's ability to obtain an unauthorized nuclear detonation from a Operations and tactics used for the protection of nuclear weapons during The category of sensitive information concerning physical security Nuclear explosive operations are performed. Includes physical security design information for all facilities, in which Unauthorized nuclear detonation from a nuclear weapon or device. Nuclear weapon transportation and nuclear weapon facility physical securityĭesign that significantly enhances an adversary's ability to obtain an Purpose of tests, general nature of nuclear explosive tested includingĮxpected or actual yields and conclusions derived from tests not to includeĬategory of sensitive information concerning the design and function of Production rate and/or stockpile quantities of nuclear weapons and their (a) Logistics, administration, other agency participation. Of operation and the design of such items. Information inherent in preshot and postshot activities necessary in the (e) Anticipated and actual strike operations. (d) Production and manufacturing techniques relating to nuclear Operation or significant design features. (c) Nuclear components or subassemblies which do not reveal theory of (b) Environmental behavior, fuzing, ballistics, yields, and effects. (a) General external weapon configuration, including size, weight, and Support the stockpile to target sequence.

Complete designĪnd operation of nonnuclear components but only information as prescribedīelow for nuclear components. The theory of operation or design of the physics package. Manufacturing and utilization information not comprehensively revealing This includes the high explosive system with its detonatorsĪnd firing unit, pit system, and nuclear initiation system as they pertain to Theory of operation or complete design of fission weapons or their uniqueĬomponents. Thermonuclear weapons or their unique components. Theory of operation (hydrodynamic and nuclear) or complete design of Sigma categories: Restricted Data and/or Formerly Restricted Data in the following categories which concern the design, manufacture, or utilization of atomic weapons, or utilization of atomic weapons or nuclear explosive devices. Sigma categories 1-13 are no longer in use. The only Sigma categories that are currently in effect are Sigma 14, Sigma 15, Sigma 18, and Sigma 20. Definitions of Sigma Classification Categories FAS |įAS Note: The 'Sigma categories' are subsets of nuclear weapons information classified under the Atomic Energy Act that are grouped by subject matter.

Sigma definition