9-1.     Introduction

9-2.     Definitions

9-3.     Visibility Standards

9-4.     Unit of Measure

9-5.     Observing Aids for Visibility

9-6.     Tower Visibility Aids

9-7.     Selection of Visibility Markers

9-8.     Observation Sites

9-9.     Dark Adaptation

9-10.   Evaluating Visibility

9-11.   Evaluating Prevailing Visibility

9-12.   Evaluating Sector Visibility

9-13.   Evaluating Variable Visibility

9-14.   Reportable Visibility Values

9-15.   Control Tower Observations and Actions at Co-Located Sites

9-16.   Additional Tower Personnel Action for Tower Visibility

9-17.   Weather Station/Contract Observer Action at Stations with Control Tower

Figure 9-1.     Reportable Visibility Values

9-18. - 9.19. Reserved