page_title: Stop sign
section_title: History
hierarchical_section_title: Stop sign / History
caption_attribution_description: English: An old, snow-covered stop sign in Grand Traverse County, Michigan.
context_page_description: A stop sign is a traffic sign designed to notify drivers that they must come to a complete stop and make sure the intersection is safely clear of vehicles and pedestrians before continuing past the sign.
context_section_description: Stop signs originated in Michigan in 1915. The first ones had black lettering on a white background and were 24 by 24 inches (61 cm × 61 cm), somewhat smaller than the current sign. As stop signs became more widespread, a rural-dominated committee supported by the American Association of State Highway Officials (AASHO) met in 1922 to standardize them and selected the octagonal shape that has been used in the United States ever since. The unique eight-sided shape of the sign allows drivers facing the back of the sign to identify that oncoming drivers have a stop sign and prevent confusion with other traffic signs. It was also chosen so that it could be identified easily at night since the original signs were not reflective. The more urban-oriented National Conference on Street and Highway Safety (NCSHS) advocated a smaller red-on-yellow stop sign. These two organizations eventually merged to form the Joint Committee on Uniform Traffic Control Devices, which in 1935 published the first Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD) detailing the stop sign's specifications.
  The MUTCD's stop sign specifications were altered eight times between 1935 and 1971. From 1924 to 1954, stop signs bore a red or black stop legend on a yellow field. Yellow was chosen because fade-resistant red materials were not available. Retro-reflective or self-lit signs were permitted in the 1935 MUTCD; retro-reflective ones were first required by the 1948 edition of the MUTCD, which also called for a 2 -foot (0.76-metre) height from the road crown to the bottom of the stop sign. The 1954 MUTCD newly specified a white stop legend on a red field, and increased the mount height specification to 5 feet in rural areas. Red traffic lights signify stop, so the new specification unified red as a stop signal whether given by a sign or a light. The current mounting height of 7 ft (2.13 m) was first specified in 1971;
caption: A snow-covered stop sign in Grand Traverse County, Michigan, with a street name sign mounted atop
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