Road signs in Iran are regulated in the INSO standard 14815-1.
[1] They generally follow the Vienna Convention on Road Signs and Signals.
Road signs are divided in three categories: Iran signed the Vienna Convention on Road Signs and Signals on November 8, 1968 and ratified it on May 21, 1976.
[2] Freeways Roads and Expressways .
Cities or Temporary signs such as detours and construction sites