(b) The vertical limits of special use airspace are measured by designated altitude floors and ceilings expressed as flight levels or as feet above mean sea level. Unless otherwise specified, the word “to” (an altitude or flight level) means “to and including” (that altitude or flight level).
(c) The horizontal limits of special use airspace are measured by boundaries described by geographic coordinates or other appropriate references that clearly define their perimeter.
(d) The period of time during which a designation of special use airspace is in effect is stated in the designation.
NEXT: Sec. 73.5 - Bearings; radials; miles.
PREVIOUS: Sec. 73.1 - Applicability.