Horizontal Launch and Landing includes pavements, infrastructure, facilities and land area directly related to horizontal launch and landing operations. Horizontal Launch and Landing includes all paved runway surfaces, aprons, or similar runway features primarily associated with the Shuttle Landing Facility. Imaginary surfaces related to airfield safety clearances consistent with FAA clearance criteria and requirements, Quantity Distance (QD) arcs, launch and landing hazard impact lines, other safety setbacks, and exposure limits are considered restrictions on the use of land in and adjacent to Horizontal Launch and Landing areas. Land covered by QD arcs is not designated as part of the Horizontal Launch and Landing land use classification.