View source for Manual on Uniform Traffic Control Devices

{{short description|National traffic control manual of the Federal Highway Administration}}
{{Use mdy dates|date=May 2021}}
{{Infobox book
| name              = Manual on Uniform Traffic Control Devices for Streets and Highways
| image             = Manual on Uniform Traffic Control Devices, December 2023 cover.png
| image_size        = 200
| border            = 
| alt               = 
| caption           = 
| authors           = {{plainlist|1=
* National Committee on Uniform Traffic Control Devices
* [[Federal Highway Administration]] }}
| country           = United States
| publisher         = Federal Highway Administration
| pub_date          = {{start date and age|1935}}
| english_pub_date  = 
| published         = December 2023
| media_type        = 
| oclc              = 
| congress          = 
| notes             = 
| website           = {{URL| https://mutcd.fhwa.dot.gov/}}
}}
The '''''Manual on Uniform Traffic Control Devices for Streets and Highways''''' (usually referred to as the '''''Manual on Uniform Traffic Control Devices''''', abbreviated '''MUTCD''') is a document issued by the [[Federal Highway Administration]] (FHWA) of the [[United States Department of Transportation]] (USDOT) to specify the standards by which [[traffic sign]]s, [[road surface marking]]s, and [[traffic light|signals]] are designed, installed, and used. Federal law requires compliance by all traffic control signs and surface markings on roads "open to public travel", including state, local, and privately owned roads (but not parking lots or gated communities).<ref name="FAQ">[https://mutcd.fhwa.dot.gov/knowledge/faqs/faq_general.htm Frequently Asked Questions - General Questions on the MUTCD]</ref> While some state agencies have developed their own sets of standards, including their own MUTCDs, these must substantially conform to the federal MUTCD. 

The MUTCD defines the content and placement of traffic signs, while design specifications are detailed in a companion volume, '''''Standard Highway Signs and Markings'''''. This manual defines the specific dimensions, colors, and fonts of each sign and road marking. The National Committee on Uniform Traffic Control Devices (NCUTCD) advises FHWA on additions, revisions, and changes to the MUTCD. The current release of the MUTCD is the 11th edition released in December 2023.

The United States is among the countries that have not ratified the [[Vienna Convention on Road Signs and Signals]]. The first edition of the MUTCD was published in 1935, 33 years before the Vienna Convention was signed in 1968, and 4 years before [[World War II]] started in 1939. The MUTCD differs significantly from the European-influenced Vienna Convention, and an attempt to adopt several of the Vienna Convention's standards during the 1970s led to confusion among many US drivers.

== History ==

=== Early 20th century  ===

At the start of the 20th century—the early days of the rural [[highway]]—each road was promoted and maintained by [[automobile associations|automobile clubs]] of private individuals, who generated revenue through club membership and increased business along cross-country routes. However, each highway had its own set of signage, usually designed to promote the highway rather than to assist in the direction and safety of travelers. Conflicts between these clubs frequently led to multiple sets of signs—sometimes as many as eleven—being erected on the same highway.<ref>{{cite web |access-date=January 11, 2024 |title=The Evolution of MUTCD: Prologue |url=https://mutcd.fhwa.dot.gov/kno-history.htm |first1=H. Gene Jr. |last1=Hawkins |date = December 15, 2023 |publisher = Federal Highway Administration }}</ref>

Government involvement did not occur until the late 1910s and early 1920s when groups from Indiana, Minnesota, and Wisconsin began surveying road to develop signage standards. They reported their findings to the Mississippi Valley Association of Highway Departments, which adopted their suggestions in 1922 for the shapes to be used for road signs. These suggestions included the familiar circular railroad crossing sign and octagonal stop sign.<ref name="Johnson">{{cite magazine |last1 = Johnson |first1 = A.E. |editor1-last = Johnson |editor1-first = A.E. |title = A Story of Road Signing |magazine = American Association of State Highway Officials: A Story of the Beginning, Purposes, Growth, Activities, and Achievements of AASHO |date = 1965 |pages = 129–138 |publisher = American Association of State Highway Officials |location = Washington, DC }}</ref>

In January 1925, [[Thomas Harris MacDonald]], chief of the federal [[Bureau of Public Roads]], published an article in which he argued that developing highway transportation in the United States to the "highest degree" would require five major innovations. Among them were "uniform markings and signs" and a "uniform [[color code]]".<ref name="MacDonald">{{cite journal |last1=MacDonald |first1=Thomas H. |title=The Urgent Necessity for Uniform Traffic Laws and Public Safety Devices |journal=American Highways |date=January 1925 |volume=4 |issue=1 |pages=5–7 |url=https://books.google.com/books?id=Z933iSTZIUUC&pg=RA7-PA7}}</ref> MacDonald argued that "drastic enforcement of uniform rules" as to "all those matters of law, regulation and safety devices which involve the human attributes in the operation of the vehicle" would improve safety on American highways, because in emergency situations, a driver and his vehicle must react as one on the basis of "reflex" and there is no time to think.<ref name="MacDonald" /> 

In January 1927, the [[American Association of State Highway and Transportation Officials|American Association of State Highway Officials]] (AASHO) published the ''Manual and Specifications for the Manufacture, Display, and Erection of U.S. Standard Road Markers and Signs'' to set standards for traffic control devices used on rural roads.<ref name="NCHRPReport484">{{cite book |last1 = Hawkins |first1 = H. Gene |last2 = Parham |first2 = Angelia H. |last3 = Womack |first3 = Katie N. |title = NCHRP Report 484: Feasibility Study for an All-White Pavement Marking System |date = 2002 |publisher = Transportation Research Board |location = Washington, DC |pages = A-1—A-7 |url = http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_484.pdf |access-date = August 10, 2020 |chapter = Appendix A: Evolution of U.S. Pavement Marking System }}</ref> Despite the title, this manual did not have any guidance on [[pavement marking]]s;<ref name="NCHRPReport484"/> at the time, the meaning of the now-obsolete phrase "road marker" overlapped with what modern speakers would call a "sign".<ref name="NCHRPReport484" /> In 1930, the National Conference on Street and Highway Safety (NCSHS) published the ''Manual on Street Traffic Signs, Signals, and Markings'', which set similar standards for urban settings, but also added specific guidance on traffic signals, pavement markings, and safety zones.<ref name="NCHRPReport484" /> Although the two manuals were quite similar, in 1931 both organizations formed a Joint Committee to develop a uniform standard for both urban streets and rural roads; this standard was the MUTCD.<ref name="Johnson" />

[[File:Mutcd cover 1935.jpg|thumb|150px|Cover of the 1937 typeset reprint of the first edition of the MUTCD published in 1935]]
The original edition of the ''Manual on Uniform Traffic Control Devices for Streets and Highways'' was published in 1935 as a [[Mimeograph|mimeographed]] document.<ref name="Johnson" /><ref name="Hawkins">{{cite journal |last1=Hawkins |first1=Gene |title=88 Years of MUTCD Editions: How the New MUTCD Evolved |journal=ITE Journal |date=April 2024 |volume=94 |issue=4 |pages=24-25 |url=https://ite.ygsclicbook.com/pubs/itejournal/2024/april-2024/live/index.html#p=24}}</ref> In 1937, the manual was republished as a typeset document.<ref name="Hawkins" /> 

In 1942, the Joint Committee was expanded to include the [[Institute of Transportation Engineers]]&nbsp;(ITE), then known as the Institute of Traffic Engineers.<ref name="Johnson" /> During World War II, the second edition of the MUTCD was released as a ''War Emergency Edition''. This included information on traffic control under [[Blackout (wartime)|blackout]] conditions and how to conserve materials needed for the war effort.<ref name="Hawkins" /> 

In 1948, three years after [[World War II]] ended, the third edition of the MUTCD was released. This edition had a different format and structure than the previous editions.<ref name="Hawkins" /> Several road signs first assumed their current appearance in this edition.<ref name="Hawkins" />  The most controversial issue during the early years of the MUTCD had been the color of center lines on roads.<ref name="NCHRPReport484" /> The 1948 MUTCD settled on white,<ref name="NCHRPReport484" /> but recommended yellow for double center lines on multi-lane highways and for center lines in no-passing zones.<ref name="NCHRPReport484" />

=== Mid-20th century ===

In 1949, the [[United Nations]] Conference on Road and Motor Transport launched a research project to develop a worldwide uniform signage scheme.<ref name="Johnson" />  In 1951, the UN conducted experiments in the US to compare the effectiveness of national traffic sign standards from around the world. Signs from six countries were placed along the road for test subjects to gauge their legibility at a distance.<ref>{{cite magazine |title = Tests of Highway Signs for United Nations |first1 = Charles R. |last1 = Waters |first2 = Gilbert W. |last2 = Treble |magazine = Traffic Engineering |date = July 1951 |page = 338 }}</ref> The test strips were located along [[Ohio State Route 104]] near [[Columbus, Ohio|Columbus]],<ref>{{cite news |title = Ohioans tell Europe to keep its signs |agency = United Press |work = [[Mansfield News Journal]] |date = March 27, 1951 |page = 11 |url = https://www.newspapers.com/clip/94492201/ |via = Newspapers.com }}</ref> [[U.S. Route 250 in Virginia|U.S. Route 250]] and [[Virginia State Route 53]] near [[Charlottesville, Virginia|Charlottesville]],<ref>{{cite news |title = Foreign Highway Signs Catch Eye |first = David |last = Barnett |work = [[The Richmond News Leader]] |location = Richmond, Virginia |date = August 21, 1951 |at = p. 1-B |url = https://www.newspapers.com/clip/94493139/ |via = Newspapers.com }}</ref> [[Minnesota State Highway 101]] near [[Minneapolis]],<ref>{{cite news |title = U.N. Highway Signs Get Test |work = [[Minneapolis Star]] |date = March 27, 1951 |page = 9 |url = https://www.newspapers.com/clip/94493204/ |via = Newspapers.com }}</ref> and other roads in New York. [[France]], [[Chile]], [[Turkey]], [[India]], and [[Southern Rhodesia]] reciprocated by installing MUTCD signs on their roads.<ref name="Air Bulletin">{{cite magazine |title = U.N. Tests New Road Signs in U.S. |magazine = Air Bulletin: World Affairs |volume=1 |issue=7 |publisher = [[United States Information Service]] |date = May 7, 1951 |pages = 4–5 |url = https://books.google.com/books?id=YPGdar6V4dsC&pg=RA1-PP73 |via = Google Books }}</ref> In the US, the experiments attracted unexpected controversy and curious onlookers who posed a hazard.<ref>{{cite news |title = Foreign Road Sign Test Arouses Some Criticism |agency = Associated Press |work = [[The Independent (Massillon)|The Independent]] |location = Massillon, Ohio |date = March 27, 1951 |page = 12 |url = https://www.newspapers.com/clip/94492382/ |via = Newspapers.com }}</ref><ref>{{cite news |title = Road Sign Test for UN Given Up |agency = Associated Press |work = [[Daily Press (Virginia)|Daily Press]] |location = Newport News, Virginia |date = March 30, 1951 |page = 13 |url = https://www.newspapers.com/clip/94492425/ |via = Newspapers.com }}</ref> By September 1951, the experts working on the project were in favor of the American proposals for stop signs (at the time, black "STOP" text on a yellow octagon), "cross road", "left or right curve", and "intersection", but were still struggling to reach consensus on symbols for "narrow road", "bumpy or uneven surface", and "steep hill".<ref name="Hoffman">{{cite news |last1=Hoffman |first1=Michael L. |title=U.N. Nearer Accord on Traffic Signs: Standard Markers of U.S. May Serve as a Basis For World System |url=https://www.nytimes.com/1951/09/23/archives/un-nearer-accord-on-traffic-signs-standard-markers-of-us-may-serve.html |access-date=July 8, 2023 |work=The New York Times |date=September 23, 1951 |page=125}}</ref>   

In 1953, after cooperating with the UN conference's initial experiments, the United States declined to sign or ratify the UN's then-proposed protocol for a worldwide system of uniform road signs.<ref name="Johnson" />  There were two major reasons behind this decision.<ref name="Johnson" /> First, most U.S. roads and streets were (and still are) under state jurisdiction.<ref name="Johnson" /><ref name="Air Bulletin" />  Second, the United States was developing modern [[controlled-access highway]]s at the time (culminating in the creation of the [[Interstate Highway System]] in 1956), and the novel problems presented by such new high-speed highways required rapid innovations in road signing and marking "that would definitely be impaired by adherence to any international code".<ref name="Johnson" />  Despite the Americans' withdrawal from the research project, the experiments eventually resulted in the Vienna Convention on Road Signs and Signals of 1968. 

The 1954 revision of the 1948 MUTCD changed the standard color of stop signs from yellow to red.<ref name="Hawkins" /> 

In 1960, the National Joint Committee on Uniform Traffic Control Devices was again reorganized to include representatives of the [[National Association of Counties]] and the [[National League of Cities]], then known as the American Municipal Association.<ref name="Johnson" /> In 1961, the MUTCD was again revised to make yellow center lines mandatory for the two exceptions where they had previously been recommended.<ref name="NCHRPReport484" />  The 1961 edition was the first edition to provide for uniform signs and barricades to direct traffic around [[Roadworks|road construction]] and maintenance operations.<ref name="Johnson" /><ref name="Hawkins" />

During the 1960s, United States Senator [[Abraham Ribicoff]] emerged as a prominent national advocate for highway safety, having previously championed the issue as governor of Connecticut.<ref name="RibicoffObituary">{{cite news |title=Ribicoff of Connecticut Dies; Governor and Senator Was 87 |url=https://www.nytimes.com/1998/02/23/nyregion/ribicoff-of-connecticut-dies-governor-and-senator-was-87.html |work=[[The New York Times]] |date=February 23, 1998 |page=A1}}</ref>  In an essay published in the July 1965 edition of ''[[The Atlantic|The Atlantic Monthly]]'', he argued that a lack of uniform standards between states contributed to highway deaths.<ref name="Ribicoff">{{cite news |last1=Ribicoff |first1=Abraham |title=Harmony on the Highways |url=https://cdn.theatlantic.com/media/archives/1965/07/216-1/132561816.pdf |work=The Atlantic Monthly |date=July 1965 |pages=80–83}}</ref> For example, two of the worst deviations from the majority rule that no passing should be marked with a solid center line were Pennsylvania, which marked no-passing zones only with signs and not center lines, and Georgia, which marked them only with a yellow line on the shoulder.<ref name="Ribicoff" />

In 1966, Congress passed the [[National Traffic and Motor Vehicle Safety Act|Highway Safety Act]], {{USPL|89|564}}, {{USStat|72|885}}, which is now codified at {{UnitedStatesCode|23|401}} ''et seq.'' It required all states to create a highway safety program by December 31, 1968, and to adhere to uniform standards promulgated by the U.S. Department of Transportation&nbsp;(USDOT) as a condition of receiving federal highway-aid funds.<ref>{{cite book |first = Edward C. |last = Fisher |title = Vehicle Traffic Law |location = Evanston, Illinois |publisher = Traffic Institute, Northwestern University |year = 1961 |edition = 1967 supp. |page = 11 }}</ref> The penalty for non-compliance was a 10% reduction in funding. In turn, taking advantage of broad rulemaking powers granted in {{UnitedStatesCode|23|402}}, the Department simply adopted the entire MUTCD by reference at {{CodeFedReg|23|655|603}}. ({{UnitedStatesCode|5|552}}(a)(1), also enacted in 1966, authorizes federal agencies to incorporate by reference technical standards published elsewhere, which means the agency may merely cite the standard and need not republish its entire text as part of the appropriate regulation.) Thus, what was formerly a quasi-official project became an official one. States are allowed to supplement the MUTCD but must remain in "substantial conformance" with the national MUTCD and adopt changes within two years after they are adopted by FHWA.

[[File:Mutcd warning signs 1971.jpg|thumb|left|170px|Warning signs introduced in the 1971 edition, combining both symbols and words]]
The 1971 edition of the MUTCD included several significant standards. The MUTCD imposed a consistent color code for [[road surface marking]]s by requiring all center lines dividing opposing traffic on two-way roads to be always painted in yellow (instead of white, which was to always demarcate lanes moving in the same direction),<ref name="NCHRPReport484" /><ref name="Section 3B-1">{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1971 |publisher = Federal Highway Administration |location = Washington, DC |page = 181 |chapter-url = https://books.google.com/books?id=gL9_gp8TUuMC&pg=PA181 |access-date = July 21, 2020 |chapter = Section 3B-1, Center Lines }}</ref> and also required that all highway guide signs (not just those on interstate highways) contain white text on a green background.<ref name="Section 2D-3">{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1971 |publisher = Federal Highway Administration |location = Washington, DC |page = 84 |chapter-url = https://books.google.com/books?id=gL9_gp8TUuMC&pg=PA84 |access-date = July 21, 2020 |chapter = Section 2D-3, Color, Reflectorization, and Illumination }}</ref>  Orange was introduced as the standard color for traffic control in work zones.<ref name="Hawkins" />

Another major change in the 1971 MUTCD, inspired by the Vienna Convention,<ref>{{cite news |title = Symbols to Replace Words on U.S. Traffic Signs |url = https://www.nytimes.com/1970/05/31/archives/symbols-to-replace-words-on-us-traffic-signs.html |work = The New York Times |date = May 31, 1970 |page = 58 }}</ref> was a preference to adopt symbols on signs in lieu of words "as rapidly as public acceptance and other considerations permit."<ref name="Section 2A-13">{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1971 |publisher = Federal Highway Administration |location = Washington, DC |page = 16 |chapter-url = https://books.google.com/books?id=gL9_gp8TUuMC&pg=PA16 |access-date = July 21, 2020 |chapter = Section 2A-13, Symbols }}</ref> During what was then expected to be a transition period, the MUTCD allowed state highway departments to use optional explanatory word plaques with symbol signs and to continue using the previous standard word message signs in certain cases.<ref name="Section 2A-13" /> Robert Conner, the chief of the traffic control systems division of the Federal Highway Administration during the 1970s, believed that symbol signs were "usually more effective than words in situations where reaction time and comprehension are important."<ref name="Lindsey">{{cite news |last1 = Lindsey |first1 = Robert |title = Signs of Progress: Road Symbols Guiding Traffic |url = https://www.nytimes.com/1972/04/23/archives/signs-of-progress-road-symbols-guiding-traffic.html |access-date = August 19, 2020 |work = The New York Times |date = April 23, 1972 |page = S22 }}</ref>  Conner was active in the Joint Committee and also represented the United States at international meetings on road traffic safety.<ref name="ConnerObituary">{{cite news |title = Robert Conner, Ex-FHA Official, Dies of Cancer |url = https://www.washingtonpost.com/archive/local/1984/12/01/robert-conner-ex-fha-official-dies-of-cancer/944fa379-9484-4f5d-9aa6-dbd7ef53f6b3/ |newspaper = The Washington Post |date = December 1, 1984 }}</ref>  However, several American traffic safety experts were concerned that American drivers would not understand the Vienna Convention's symbols, which is why the MUTCD allowed for explanatory word plaques.<ref name="Hebert">{{cite news |last1=Hebert |first1=Ray |title=New Traffic Signs Bloom as California Goes International |work=Los Angeles Times |date=January 30, 1972 |page=1}}</ref>  Most of the repainting to the 1971 standard was done between 1971 and 1974, with a deadline of 1978 for the changeover of both the markings and signage.

{{multiple image
| align             = right
| total_width       = 200
| image1            = MUTCD W3-6.svg
| alt1              = A diamond-shaped with yellow background and black border, with the words "Draw Bridge"
| image2            = Vienna Convention road sign Ab-5-V1.svg
| alt2              = A diamond-shaped with yellow background and black border, with a symbol of an open draw bridge
| footer            = The draw bridge warning sign (left) is one of the several signs under the MUTCD that remain{{when|date=January 2024}} text-only, while its equivalent under the Vienna Convention (right) displays a symbol of an open draw bridge.
}}
The U.S. adoption of several Vienna Convention-inspired symbol signs during the 1970s was a failure. For example, the lane drop symbol sign was criticized as baffling to U.S. drivers—who saw a "big milk bottle"—and therefore quite dangerous, since by definition it was supposed to be used in situations where drivers were about to run out of road and needed to merge into another lane immediately.<ref name="Conniff">{{cite news |last1 = Conniff |first1 = James C.G. |title = Danger: Signs Ahead |url = https://www.nytimes.com/1975/03/30/archives/danger-signs-ahead-misleading-highway-signs-raise-blood-pressure.html |access-date = August 19, 2020 |work = The New York Times |date = March 30, 1975 |page = 183 }}</ref>  American highway safety experts ridiculed it as the "Rain Ahead" sign.<ref name="Conniff" /> Many American motorists were bewildered by the Vienna Convention's symbol sign with two children on it, requiring it to be supplemented with a "School Xing" plaque.<ref name="Hazlett">{{cite news |last1 = Hazlett |first1 = Bill |title = Some Confusing: Wordless Traffic Signs Popping Up |work = Los Angeles Times |date = March 23, 1972 |page = E1 }}</ref> (The American "School Xing" symbol was later redesigned to depict an adult crossing together with a child.) However, several signs from the Vienna Convention were successfully adopted into the 1971 MUTCD, including the red "Yield" sign, which replaced the previous yellow version,<ref>{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1961 |publisher = Federal Highway Administration |location = Washington, DC |page = 29 |chapter = Section 1B-7}}</ref><ref>{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1971 |publisher = Federal Highway Administration |location = Washington, DC |page = 34 |chapter = Section 2B-7}}</ref> and the "Do Not Enter" sign, which replaced a word-only version.<ref>{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1961 |publisher = Federal Highway Administration |location = Washington, DC |page = 42 |chapter = Section 1B-26}}</ref><ref>{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1971 |publisher = Federal Highway Administration |location = Washington, DC |page = 47 |chapter = Section 2B-25}}</ref> Because the Vienna Convention version was circular, it was given a square backing to conform with the MUTCD shape for regulatory signs, and the words "DO NOT ENTER" were superimposed to ensure American driver comprehension.

The 1971 MUTCD's preference for a rapid transition to symbols over words were removed in the 1978 MUTCD.<ref>{{cite book |last1 = American Association of State Highway Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 1978 |publisher = Federal Highway Administration |location = Washington, DC |page = 2A-6 |chapter = Section 2A-13, Symbols }}</ref> After 1971, FHWA formally assumed responsibility for publishing the MUTCD. The 1971 MUTCD was revised eight times. In 1978, the MUTCD physical format was changed to a [[ring binder]] whose revisions were published as replacement pages (i.e., an interfiled [[looseleaf service]]).<ref name="Hawkins" /> The 1978 MUTCD was subject to four revisions, and the subsequent 1988 MUTCD was subject to seven revisions.<ref name="Hawkins" />

=== 21st century ===

The 2000 MUTCD was the first to be available on the internet and to use metric units.<ref name="Hawkins" /> Due to a number of significant flaws, the 2003 MUTCD was envisioned primarily for the purpose of addressing errata in the 2000 MUTCD.<ref name="Hawkins" /> The 2000 and 2003 MUTCDs each eliminated a symbol sign that had long been intended to replace a word message sign: "Pavement Ends" (in 2000) and "Narrow Bridge" (in 2003).<ref name="2003Rev1Intro">{{cite book |last1 = American Association of State Highway and Transportation Officials |last2 = National Joint Committee on Traffic Control Devices |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 2003 |publisher = Federal Highway Administration |location = Washington, DC |url = https://mutcd.fhwa.dot.gov/HTM/2003r1/intro/intro.htm |access-date = August 26, 2020 |chapter = Introduction }}</ref>

The tenth edition of the MUTCD was published in 2009, with revisions in 2012.<ref name="2012revisions">{{cite web |last1 = American Association of State Highway and Transportation Officials |last2 = National Joint Committee on Traffic Control Devices |title = Change List for Revision Numbers 1 and 2, Dated May 2012, to the 2009 Edition of the MUTCD |year = 2012 |publisher = Federal Highway Administration |location = Washington, DC |url = https://mutcd.fhwa.dot.gov/htm/2009r1r2/mutcd2009r1r2cl.htm |access-date = May 9, 2021 }}</ref> This was the first editing to cover traffic control devices on private property.<ref name="Hawkins" />  

The [[Infrastructure Investment and Jobs Act]]&nbsp;(IIJA) of 2021 required the USDOT to update the MUTCD every four years,<ref>{{cite web |url=https://mutcd.fhwa.dot.gov/mutcd11status.htm |archive-url=https://web.archive.org/web/20220306074815/https://mutcd.fhwa.dot.gov/mutcd11status.htm |url-status=dead |archive-date=March 6, 2022 |title=Status of Rulemaking for the Eleventh Edition of the MUTCD |date=March 2, 2022 |access-date=March 2, 2023 |publisher=Federal Highway Administration}}</ref> and the eleventh edition was released in 2023.<ref name="Woodhouse">{{cite news |last1=Woodhouse |first1=Skylar |title=Rules of the Road Get a Long-Awaited Update in the US |url=https://www.bloomberg.com/news/articles/2023-12-19/us-roadbuilding-bible-gets-update-as-pedestrian-deaths-rise |access-date=December 20, 2023 |work=Bloomberg |date=December 19, 2023}}</ref><ref>{{cite press release |url=https://www.transportation.gov/briefing-room/fhwa-releases-new-traffic-control-device-manual-updates-improve-safety-pedestrians |title=FHWA Releases New Traffic Control Device Manual with Updates to Improve Safety for Pedestrians, Bicyclists, and All Road Users |date=December 19, 2023 |access-date=December 27, 2023 |publisher=U.S. Department of Transportation}}</ref>  This edition allowed painted red bus lanes, rules allowing more crosswalks and traffic signals, new rules for determining speed limits, signage for shoulders that are used part-time as traffic lanes, and new signage for [[electric vehicle charging station]]s and [[autonomous vehicle]]s.<ref name="2023_revision_final" /> It also added painted green bike lanes, bike boxes, and bike-specific traffic lights. Rectangular Rapid-Flashing Beacons (RRFBs) were also added to the MUTCD; a pedestrian beacon for uncontrolled intersections consisting of two rectangular lights, side-by-side, which alternate flashing, under a yellow diamond with a walking person on it, above an arrow pointing out the crosswalk.<ref name="2023_revision_final">[https://public-inspection.federalregister.gov/2023-27178.pdf RIN 2125-AF85 National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for Streets and Highways; Revision], III. Summary of the Major Provisions of the Regulatory Action in Question</ref> RRFBs were previously on interim approval by FHWA since March 20, 2018.<ref>{{cite web |access-date=January 12, 2024 |title=Interim Approval 21 – Rectangular Rapid-Flashing Beacons at Crosswalks - Interim Approvals Issued by FHWA |url=https://mutcd.fhwa.dot.gov/resources/interim_approval/ia21/index.htm |website=MUTCD |publisher=Federal Highway Administration |date=March 20, 2018}}</ref> Transportation safety advocates criticized the changes as not going far enough to deal with a substantial spike in pedestrian fatalities, especially guidance setting speed limits [[85th percentile speed|based on the 85th percentile of actual driving speeds]].<ref>{{cite news |url=https://www.npr.org/2023/12/31/1222174861/road-street-design-traffic-mutcd |title=The rules of the road are changing, but not fast enough for everyone |date=December 31, 2023 |first=Joel|last=Rose|work=NPR}}</ref><ref>[https://t4america.org/2023/12/20/press-statement-newly-updated-mutcd-doesnt-go-far-enough-to-protect-pedestrians/ Press statement: Newly updated MUTCD doesn’t go far enough to protect pedestrians]</ref><ref>{{cite web|url=https://usa.streetsblog.org/2023/12/19/feds-advocates-talk-about-whats-in-the-new-mutcd-and-what-isnt|title=Feds, Advocates Talk About What’s In The New MUTCD (And What Isn't)!|first=Kea|last=Wilson|work=Streetsblog USA|date=2023-12-19}}</ref>

== Development ==
Proposed additions and revisions to the MUTCD are recommended to FHWA by the National Committee on Uniform Traffic Control Devices (NCUTCD), a private, non-profit organization. The NCUTCD also recommends interpretations of the MUTCD to other agencies that use the MUTCD, such as state departments of transportation. NCUTCD develops public and professional awareness of the principles of safe traffic control devices and practices and provides a forum for qualified individuals to exchange professional information.

The NCUTCD is supported by twenty-one sponsoring organizations, including transportation and engineering industry groups (such as [[AASHTO]] and [[American Society of Civil Engineers|ASCE]]), safety organizations (such as the [[National Safety Council]] and [[Advocates for Highway and Auto Safety]]), and the [[American Automobile Association]]. Each sponsoring organization promotes members to serve as voting delegates within the NCUTCD.

== Adoption ==
[[File:U.S. states by 2009 MUTCD adoption.svg|thumb|300px|Map showing state adoption of the 2009 MUTCD:<br />{{legend|#1b9e77|Adopted national MUTCD}}
{{legend|#d95f02|Adopted national MUTCD with state supplement}}
{{legend|#7570b3|Adopted state-specific MUTCD}}]]
[[File:Entering Nevada At Crystal Bay.jpg|thumb|An example of state-by-state variations: California (foreground) paints a black line to help drivers see a double yellow line demarcating opposing traffic, while Nevada (background) does not]]
Eighteen states have adopted the national MUTCD as is. Twenty-two states, the [[Washington, D.C.|District of Columbia]], [[Puerto Rico]], and the [[United States Department of Defense]] through the [[Military Surface Deployment and Distribution Command]] (SDDC) have all adopted supplements to the MUTCD. Ten states have adopted their own editions of the MUTCD "in substantial conformance to" an edition of the national MUTCD, annotated throughout with state-specific modifications and clarifications.<ref>{{cite web |title = MUTCDs & Traffic Control Devices Information by State |work = Manual on Uniform Traffic Control Devices |publisher = Federal Highway Administration |date = July 14, 2020 |access-date = July 12, 2021 |url = https://mutcd.fhwa.dot.gov/resources/state_info/ }}</ref><ref>{{cite book |title = Manual de Rotulación para las Vías Públicas en Puerto Rico |publisher = [[Puerto Rico Highways and Transportation Authority]] |location = San Juan, Puerto Rico |date = 2020 |url = https://act.dtop.pr.gov/pdf/transito/Manual_Rotulacion.pdf |language = es }}</ref><ref>{{cite book |title = Department of Defense Supplement to the National Manual on Uniform Traffic Control Devices for Streets and Highways |publisher = [[Military Surface Deployment and Distribution Command]] |location = Scott Air Force Base, Illinois |date = 2015 |url = https://www.sddc.army.mil/sites/TEA/Functions/SpecialAssistant/TrafficEngineeringBranch/Documents/MUTCD_DOD_Supplement_Revision_20150601.pdf |archive-url = https://web.archive.org/web/20161023035355/https://www.sddc.army.mil/sites/TEA/Functions/SpecialAssistant/TrafficEngineeringBranch/Documents/MUTCD_DOD_Supplement_Revision_20150601.pdf |url-status = dead |archive-date = October 23, 2016 }}</ref><ref>{{cite web |title = MUTCD |publisher = Military Surface Deployment and Distribution Command Transportation Engineering Agency |location = Scott Air Force Base, Illinois |accessdate = November 30, 2021 |url = https://www.sddc.army.mil/sites/TEA/Functions/SpecialAssistant/TrafficEngineeringBranch/BMTE/calcSigns/SignsAndMarkingsTurtorials/Pages/default.aspx |archive-url = https://web.archive.org/web/20150630040802/http://www.sddc.army.mil/sites/TEA/Functions/SpecialAssistant/TrafficEngineeringBranch/BMTE/calcSigns/SignsAndMarkingsTurtorials/Pages/default.aspx |url-status = dead |archive-date = June 30, 2015 }}</ref> The [[Guam Department of Public Works]] has also adopted the MUTCD in some form.<ref>{{cite web |title = List of Approved Requests for Interim Approval |work = Manual on Uniform Traffic Control Devices |publisher = Federal Highway Administration |date = May 15, 2020 |access-date = January 11, 2021 |url = https://mutcd.fhwa.dot.gov/resources/interim_approval/ialistreq.htm#ia10 }}</ref>

The following state-specific MUTCD editions are currently in effect:

* [[California Department of Transportation]]: ''[[California Manual on Uniform Traffic Control Devices]]'' (CA&nbsp;MUTCD)
* [[Delaware Department of Transportation]]: ''[[Delaware Manual on Uniform Traffic Control Devices]]'' (DE&nbsp;MUTCD)
* [[Indiana Department of Transportation]]: ''[[Indiana Manual on Uniform Traffic Control Devices]]'' (IMUTCD)
* [[Maryland State Highway Administration]]: ''[[Maryland Manual on Uniform Traffic Control Devices]]'' (MdMUTCD)
* [[Michigan Department of Transportation]]: ''[[Michigan Manual on Uniform Traffic Control Devices]]'' (MMUTCD)
* [[Minnesota Department of Transportation]]: ''[[Minnesota Manual on Uniform Traffic Control Devices]]'' (MN&nbsp;MUTCD)
* [[Missouri Department of Transportation]]: ''[[Engineering Policy Guide]]'' (EPG), section 900
* [[Ohio Department of Transportation]]: ''[[Ohio Manual of<!-- sic --> Uniform Traffic Control Devices]]'' (OMUTCD)
* [[Texas Department of Transportation]]: ''[[Texas Manual on Uniform Traffic Control Devices]]'' (TMUTCD)
* [[Utah Department of Transportation]]: ''[[Utah Manual on Uniform Traffic Control Devices]]'' (Utah MUTCD)

== Enforcement ==
Federal funding is tied to compliance and serves as an enforcement mechanism for state and local governments.<ref>{{USCode|23|109}}(d)</ref><ref name="FAQ" /> For private property owners, FHWA recommends "encouragement" rather than punishment.<ref name="FAQ" /> The use of non-compliant devices can also create liability in [[tort]] lawsuits for private owners and some governments.<ref name="FAQ" />

From 2014 to 2018, New York placed over 500 non-compliant "[[I Love New York]]" tourism destination signs along its highways and expressways to encourage tourists to visit nearby destinations, especially those in economically depressed [[Upstate New York]].<ref name="Campbell">{{cite news |last1=Campbell |first1=Jon |title=New NY highway signs are illegal, feds say |url=https://www.pressconnects.com/story/news/politics/blogs/vote-up/2016/11/02/ny-highway-signs-illegal/93173466/ |work=pressconnects.com |date=November 2, 2016}}</ref><ref name="Campbell2">{{cite news |last1=Campbell |first1=Jon |title=Feds say no, but NY replacing wind-swept signs |url=https://www.pressconnects.com/story/news/local/new-york/2017/03/20/wind-swept-love-ny-signs/99429148/ |work=pressconnects.com |date=March 20, 2017}}</ref>  FHWA contended that the signs violated numerous MUTCD rules, along with the general principle of the MUTCD that signs should be simple so that they are "easy to identify, comprehend and understand in a matter of seconds as you are driving".<ref name="Campbell" />  After FHWA threatened to withhold $14 million in federal funding, New York removed the signs in November 2018.<ref>{{cite news |title=I (No Longer) Love New York? Feds Make State Take Down Tourism Signs |url=https://www.cbsnews.com/newyork/news/i-love-ny-roadside-signs/ |work=CBS News New York |date=November 9, 2018}}</ref>

== Other jurisdictions ==
{{main|Traffic signs by country}}
{{multiple image
| align             = right
| total_width       = 200
| image1            = MUTCD R2-1.svg
| alt1              = A vertical rectangular white sign with a black border, with the words "SPEED LIMIT" above the number "50"
| image2            = Vienna Convention road sign C14-V1-50.svg
| alt2              = A circular white sign with a red border, with the number "50"
| footer            = Under the MUTCD, the standard speed limit sign (left) used only in the United States includes the words "speed limit" above the number (which is in mph),<ref>{{cite book |title = Manual on Uniform Traffic Control Devices for Streets and Highways |date = 2009 |publisher = Federal Highway Administration |location = Washington, DC |chapter-url = https://mutcd.fhwa.dot.gov/htm/2009r1r2/part2/fig2b_03_longdesc.htm |access-date = May 23, 2021 |chapter = Figure 2B-3. Speed Limit and Photo Enforcement Signs and Plaques }}</ref> while the standard one under the Vienna Convention (right) only requires the number which is used in most countries (which is mostly in km/h).<ref>{{cite book |title = Vienna Convention on Road Signs and Signals |edition = 2006 consolidated |publisher = United Nations Economic Commission for Europe |location = Geneva, Switzerland |url = https://unece.org/DAM/trans/conventn/Conv_road_signs_2006v_EN.pdf |access-date = May 23, 2021 |pages = 41, 91 }}</ref>
}}

The United States is among the majority of countries around the world that have not ratified the Vienna Convention on Road Signs and Signals (based primarily on European signage traditions), and the MUTCD differs significantly from the Vienna Convention. Apart from the 1971 effort to adopt several Vienna Convention-inspired symbol signs (as explained above), achieving worldwide uniformity in traffic control devices was never a priority for AASHTO because the number of motorists driving regularly on multiple continents was relatively small during the 20th century.<ref name="Johnson" />

[[Warning sign]]s (alerting drivers of unexpected or hazardous conditions) tend to be more verbose than their Vienna Convention counterparts.<ref name="Johnson" /> On the other hand, MUTCD guide signs (directing or informing road users of their location or of destinations) tend to be less verbose, since they are optimized for reading at high speeds on freeways and expressways.<ref name="Johnson" />

The MUTCD lacks a [[Mandatory sign|mandatory sign group]] like the Vienna Convention does, a separate category for those signs like "Right Turn Only" and "Keep Right" that tell traffic what it must do instead of what it must not do. Instead, the MUTCD primarily classifies them with the other [[regulatory sign]]s that inform drivers of traffic regulations.<ref>{{Cite journal |last1=Babić |first1=Darko |last2=Babić |first2=Dario |last3=Fiolic |first3=Mario |last4=Ferko |first4=Marija |date=2022-10-12 |title=Road Markings and Signs in Road Safety |journal=Encyclopedia |language=en |volume=2 |issue=4 |pages=1738–1752 |doi=10.3390/encyclopedia2040119 |doi-access=free |issn=2673-8392}}</ref>

== See also == 
* [[Comparison of MUTCD-influenced traffic signs]]
* [[Comparison of traffic signs in English-speaking territories]]
* [[Road signs in the United States]]
* [[Traffic Signs Regulations and General Directions]], for the UK

== References ==
{{reflist}}

== External links ==
{{Sister project links|c=yes|s=Manual on Uniform Traffic Control Devices for Streets and Highways, 11th Edition|wikt=n|n=n|q=n|b=n |v=n|voy=n|species=n}}
* {{official website}}
* [https://ncutcd.org/ National Committee on Uniform Traffic Control Devices] (NCUTCD) website
* [https://ceprofs.civil.tamu.edu/ghawkins/MUTCD-History.htm MUTCD History] by H. Gene Hawkins

{{Road signs in the US states by the adoption of MUTCD}}
{{Traffic signs|state=collapsed}}

[[Category:Manual on Uniform Traffic Control Devices| ]]