Road signs in the United States
Road signs in the United States are, for the most part, standardized by federal regulations, most notably in the Manual on Uniform Traffic Control Devices (MUTCD) and its companion volume the Standard Highway Signs (SHS). == Adoption and compliance == The 11th edition of the MUTCD was released on December 19, 2023.
Source: Wikipedia — Road signs in the United States (CC BY-SA 4.0)