or "Secret//Restricted Data-Critical Nuclear Weapon Design Information" (S//RD-CNWDI) depending on the type of information a document contains. Formerly Restricted Data (FRD) is a category also designated in the Atomic Energy Act of 1954. Despite its name, it does not mean that the information so designated is unclassified. It means that they have been downgraded specifically for the purpose of sharing among military agencies as "National Security Information". It is defined as "Classified information which has been removed from the Restricted Data category after DOE and the Department of Defense have jointly determined that it relates primarily to the military utilization of atomic weapons, and can be adequately safeguarded as national security information." See also Critical Nuclear Weapon Design Information References United States government secrecy Nuclear secrecy