; or (B) shall be composed of glass employing— (i) elements that preclude bird collisions without completely obscuring vision, such as secondary facades, netting, screens, shutters, and exterior shades; (ii) ultraviolet (UV) patterned glass that contains UV-reflective or contrasting patterns that are visible to birds; (iii) patterns on glass designed in accordance with a rule that restricts horizontal spaces to less than 2 inches high and vertical spaces to less than 4 inches wide, commonly referred to as the 2 × 4 rule ; (iv) opaque, etched, stained, frosted, or translucent glass; or (v) any combination of the methods described in this subparagraph. (2) At least 60 percent of the exposed facade material above 40 feet shall meet the standard described in paragraph (1)(A) or (1)(B). (3) There shall not be any transparent passageways or corners. (4) All glass adjacent to atria or courtyards containing water features, plants, and other materials attractive to birds shall meet the standard described in paragraph (1)(B). (5) Outside lighting shall be appropriately shielded and minimized. (b) Monitoring The Administrator shall take such actions as may be necessary to ensure that actual bird mortality is monitored at each public building. (c) Existing buildings and lighting (1) In general The Administrator, where practicable, as determined by the Administrator, shall reduce exterior building and site lighting for each public building. (2) Use of automatic control technologies In carrying out paragraph (1), the Administrator shall make use of automatic control technologies, including timers, photo-sensors, and infrared and motion detectors. (d) Exempt buildings This section shall not apply to— (1) a historic building of national significance within the meaning of the Act of August 21, 1935 ( 16 U.S.C. 461 et seq.; commonly known as the Historic Sites, Buildings, and Antiquities Act); (2) the White House and its grounds; (3) the Supreme Court building and its grounds