Information that could be used by an adversary to harm the U. S. Or its allies and thus must be protected. The NRC has two types of classified information. The first type, known as national security information, is information that is classified by an Executive Order. Its release would damage national security to some degree. The second type, known as restricted data, is information that is classified by the Atomic Energy Act. It would assist individuals or organisations in designing, manufacturing, or using nuclear weapons. Access to both types of information is restricted to authorised persons who have been properly cleared and have a "need to know" the information for their official duties.