41 C.F.R. § 102-81.25
Each agency occupying a Federal facility or Federal grounds under the jurisdiction, custody, or control of GSA, including those facilities and grounds that have been delegated by the Administrator of General Services, for nonmilitary activities is responsible for implementing, maintaining, and upgrading the physical security standards, except where the Director of National Intelligence determines that compliance would jeopardize intelligence sources and methods or the Secretary of Energy determines that compliance would conflict with the authorities of the Secretary of Energy over Restricted Data and Special Nuclear Material under, among others, sections 141, 145, 146, 147, and 161 of the Atomic Energy Act of 1954, as amended, the Department of Energy Organization Act, or any other statute. An occupant agency, if it is the only Federal occupant agency in the building, or the Facility Security Committee (FSC), as applicable, uses the facility security assessment reports they receive from the U.S. Department of Homeland Security-Federal Protective Service to inform deliberations regarding recommended countermeasures and other security-related actions. GSA will facilitate the implementation of the countermeasures or other actions after occupant agency or FSC approval, as applicable, and commitment of each occupant agency to pay its pro rata share of the cost.
41 C.F.R. §102-81.25