Road signs used by countries in the Americas are significantly influenced by the Manual on Uniform Traffic Control Devices (MUTCD), first released in 1935, reflecting the influence of the United States throughout the region.[1] Other non-American countries using road signs similar to the MUTCD include Australia, Indonesia, Ireland, Japan, Malaysia, New Zealand, and Thailand. They, along with the US Virgin Islands, are also the only countries listed here which drive on the left—with the exception of Liberia and the Philippines (though partial), both of which drive on the right.
There are also a number of American signatories to the Vienna Convention on Road Signs and Signals: Argentina, Brazil, Chile, Cuba, Ecuador, French Guiana, Paraguay, and Suriname. Of those, only Chile, Cuba, and French Guiana have ratified the treaty.
Mandatory action signs in the Americas tend to be influenced by both systems. Nearly all countries in the Americas use yellow diamond warning signs. Recognizing the differences in standards across Europe and the Americas, the Vienna convention considers these types of signs an acceptable alternative to the triangular warning sign.[2] However, UN compliant signs must make use of more pictograms in contrast to more text based US variants. Indeed, most American nations make use of more symbols than allowed in the US MUTCD.
Unlike in Europe, considerable variation within road sign designs can exist within nations, especially in multilingual areas.
The main differences between traffic signs influenced by the MUTCD relate to:
Below is a table of the main languages used. (In non-English speaking countries, English is frequently included on signs near airports and tourist areas.)