FAA Chart Users’ Guide - VFR Chart Symbology - Flyway Planning Chars 45 Air Defense Identification Zone (ADIZ) Special Use Airspace Temporary Flight Restriction (TFR) Relating To  National Security Flight Restricted Zone (FRZ) Relating To National Se- curity AIRSPACE INFORMATION (Continued) Example: Washington DC Example: Washington DC Appropriate notes as required may be shown. Only the airspace effective  below 18,000 feet MSL is  shown. The type of area shall be  spelled out in large areas if  space permits. Note: Delimiting line not  shown when it coincides  with International Bound- ary, projection lines or other  linear features.