MUTCD 11th Edition

Page 1PART 1
GENERAL

CHAPTER 1A. GENERAL
Section 1A.01 Purpose of the MUTCD

Support:01
The purpose of the MUTCD is to establish uniform national criteria for the use of traffic control devices thatmeet the needs and expectancy of road users on all streets, highways, pedestrian and bicycle facilities, and site
roadways open to public travel.
02
This purpose is achieved through the following objectives:
A. Promote safety, inclusion, and mobility for all users of the road network;
B. Promote efficiency through creating national uniformity in the meaning and appearance of traffic
control devices;
C. Promote national consistency in the use, installation, and operation of traffic control devices; andD. Provide basic principles for traffic engineers to use in making decisions regarding the use, installation,
operation, maintenance, and removal of traffic control devices.
03
Uniformity of the meaning of traffic control devices is vital to their effectiveness. Uniformity means treating
similar situations in a similar way. Uniformity of devices simplifies the task of the road user because it aids inrecognition and understanding, thereby reducing perception/reaction time. Uniformity assists road users, law
enforcement officers, and traffic courts by giving everyone the same interpretation. Uniformity assists public
highway officials through efficiency in manufacture, installation, maintenance, and administration.
04
The use of uniform traffic control devices also requires uniform and appropriate application.
05
The applicability of the MUTCD to facilities open to public travel is independent of the type of ownership or
jurisdiction (public or private) and the source of funding (Federal, State, local, or private).
06
This Manual presumes the user of the MUTCD has sufficient working knowledge, professional training andexperience, and education in the principles of traffic engineering. Other resources can be consulted to understandthe basis for decisions that are made in which engineering study or judgment will be applied.

Section 1A.02 Traffic Control Devices – General Description

Support:As defined in Section 1C.02 of this Manual, traffic control devices include all signs, signals, markings,
channelizing devices, or other devices that use colors, shapes, symbols, words, sounds, and/or tactile information
for the primary purpose of communicating a regulatory, warning, or guidance message to road users on a street,highway, pedestrian facility, bikeway, pathway, or site roadway open to public travel.
02
Infrastructure elements that restrict the road user’s travel paths or vehicle speeds, such as islands, curbs, speed
humps, and other raised roadway surfaces, are not traffic control devices. Transverse or longitudinal rumble strips
are also not traffic control devices. Operational devices associated with the application of traffic control strategies
such as fencing, roadway lighting, barriers, and attenuators are shown in this Manual for context, but their design,
application, and usage are not specified since they are not traffic control devices.
03
Certain types of signs and other devices that do not have any traffic control purpose are sometimes placed
within the highway right-of-way by or with the permission of the public agency or the official having jurisdiction
over the street or highway. These signs and other devices are not considered to be traffic control devices andprovisions regarding their design and use are not included in this Manual. Among these signs and other devices
are the following:
A. Devices whose purpose is to assist highway maintenance personnel, such as markers to guide snowplow
operators, devices that identify culvert and drop inlet locations, and devices that precisely identify highway
locations for maintenance or mowing purposes;
B. Devices whose purpose is to assist fire or law enforcement personnel, such as markers that identify
fire hydrant locations, signs that identify fire or water district boundaries, speed measurement
pavement markings, small indicator lights to assist in enforcement of red light violations, and photoenforcement systems;
C. Devices whose purpose is to assist utility company personnel and highway contractors, such as markers
that identify underground utility locations;
D. Signs posting local non-traffic ordinances; andE. Signs giving civic organization meeting information.
01

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MUTCD 11th Edition

Section 1A.03 Target Road Users

Support:Traffic control devices can be targeted at operators of motor vehicles, including driving automation systems,
and at vulnerable road users.
02
Targeted operators of motor vehicles include motorists, public transportation operators, truck drivers, andmotorcyclists. Targeted users also include vulnerable road users, who have little to no protection from crash forces.
These users are defined in Title 23, U.S.C. 148(a). They include bicyclists and pedestrians, including persons
with disabilities. Pedestrians with disabilities might be blind or vision-impaired, have mobility limitations, orother impairments. Protection of vulnerable users is a priority in this Manual as directed in Section 11135 of theInfrastructure Investment and Jobs Act.
03
Operators of motor vehicles and vulnerable road users are both likely to be present on roadways where
adjacent land use suggests that trips could be served by varied modes. Application of traffic control devices onthese roadways requires careful consideration of measures to set and design for appropriate speeds; separation ofvarious users in time and space; improvement of connectivity and access for pedestrians, bicyclists, and transit
riders, including for people with disabilities; and implementation of safety countermeasures.
01

Section 1A.04 Use of the MUTCD

Support:Traffic control device principles in the MUTCD are developed for and used by individuals who are duly
authorized and qualified to conduct traffic control device activities.
Standard:
02
Where the content of this Manual requires a decision for implementation, such decisions shall be madeby an engineer, or an individual under the supervision of an engineer, who has the appropriate levels of
experience and expertise to make the traffic control device decision. Those decisions shall be made using
engineering judgment or engineering study, as required by the MUTCD provision.
Support:03
Section 1C.02 contains definitions of “engineering study” and “engineering judgment.”
Guidance:04
In making traffic control device decisions, individuals should consider the impacts of the decision on thefollowing: safety and operational efficiency (mobility) of all road users at that location, the effective use of agency
resources, cost-effectiveness, and enforcement and education aspects of traffic control devices.
Support:05
Throughout this Manual the headings Standard, Guidance, Option, and Support, the meanings of which aredefined in Section 1C.01, are used to classify the nature of the text that follows. Figures and tables, including thenotes contained therein, supplement the text and might constitute a Standard, Guidance, Option, or Support. The
user needs to refer to the appropriate text to classify the nature of the figure, table, or note contained therein.
Guidance:06
Except when a specific numeral is required or recommended by the text of a Section of this Manual, numerals
displayed on the images of devices in the figures that specify quantities such as times, distances, speed limits,
and weights should be regarded as examples only. When installing any of these devices, the numerals should beappropriately altered to fit the specific situation.
07
Similarly, destination names, route numbers, and State route shields that are displayed on the images ofdevices in the figures should be regarded as examples only. When installing any of these devices, the destination
names, route numbers, and State route shields should be appropriately altered to fit the specific situation.
Support:08
The information contained in Paragraphs 9 and 10 of this Section will be useful when reference is being madeto a specific portion of text in this Manual.
09
There are nine Parts in this Manual and each Part includes one or more Chapters. Each Chapter includes one
or more Sections. Parts are identified by a single-digit numerical identification, such as “Part 2 – Signs.” Chapters
are identified by the Part number and a letter, such as “Chapter 2B – Regulatory Signs.” Sections are identified by
the Chapter number and letter followed by a decimal point and a 2-digit number, such as “Section 2B.03 – Size ofRegulatory Signs.” In some Chapters, the Sections are grouped together by subject into unnumbered sub-chapterswith a heading, such as “Signing for Right-of-Way at Intersections” (for Sections 2B.06 through 2B.20).
10Each Section includes one or more paragraphs. The paragraphs are indented and are identified by a number.
Paragraphs are counted from the beginning of each Section without regard to the intervening text headings(Standard, Guidance, Option, or Support) or any intervening text in embedded Figures or Tables. Someparagraphs have lettered or numbered items. As an example of how to cite this Manual, the phrase “[n]ot lessthan 40 feet beyond the stop line” that appears in Section 4D.08 of this Manual would be referenced in writing
as “Section 4D.08, Par.1, A.1,” and would be verbally referenced as “Item A.1 of Paragraph 1 of Section 4D.08.”
01

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Section 1A.05 Relation to Other Publications

Standard:
To the extent that they are incorporated by specific reference, the latest editions of the following
publications, shall be a part of this Manual: “Standard Highway Signs” publication (FHWA), and “Color
Specifications for Retroreflective Sign and Pavement Marking Materials” (appendix to Subpart F of Part
655 of Title 23 of the Code of Federal Regulations).
Support:02
The “Standard Highway Signs” publication includes standard alphabets and symbols and arrows for signs andpavement markings.
03
The MUTCD is not a roadway design manual, and engineers seeking guidance on design should refer toappropriate roadway design guides recognized by the Federal Highway Administration as needed for the design
application.
04
Other publications are referenced in this Manual as useful resources, but they are not regulatory in nature andare not independently legally enforceable.
01

Section 1A.06 Uniform Vehicle Code – Rules of the Road

Support:The “Uniform Vehicle Code” (UVC) is one of the publications referenced in the MUTCD. The UVC contains
a model set of motor vehicle codes and traffic laws for use throughout the United States, the intent of which isto promote national uniformity in these laws. The Rules of the Road contained in the UVC are intended to berecommendations for States to adopt in their State statutes and are not independently legally enforceable.
Guidance:
02
The actions required of road users to obey regulatory devices should be specified by State statute, or in cases
not covered by State statute, in local ordinances or resolutions. Such statutes, ordinances, and resolutions should
be consistent with the “Uniform Vehicle Code.”
01

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MUTCD 11th Edition

CHAPTER 1B. LEGAL REQUIREMENTS FOR TRAFFIC CONTROL DEVICES
Section 1B.01 National Standard

Standard:
01
The Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD) is incorporated
by reference in 23 Code of Federal Regulations (CFR), Part 655, Subpart F and shall be recognized as thenational standard for all traffic control devices installed on any street, highway, bikeway, or site roadway
open to public travel (see definition in Section 1C.02) in accordance with 23 U.S.C. 109(d) and 402(a).
02
In accordance with 23 CFR 655.603(a), the MUTCD shall apply to all of the following types of facilities:
A. Any street, roadway, or bikeway open to public travel, either publicly or privately owned;
B. Streets and roadways on sites that are off the public right-of-way that are open to public travel
without full-time access restrictions. Examples include roadways within shopping centers, officeparks, airports, sports arenas, other similar business and/or recreation facilities, governmental
office complexes, schools, universities, recreational parks, and other similar publicly-owned
complexes and/or recreation facilities. The above-described examples of streets and roadways arereferred to in this Manual as site roadways open to public travel;
C. Publicly-owned toll roads, including those under the jurisdiction of a public agency, publicauthority, or public-private partnership;
D. Privately-owned toll roads where the public is allowed to travel without access restriction.
This includes gated toll roads or roadways where the general public is able to pay to access thefacility; andE. Grade crossings of publicly-owned roadways with railroads or light rail transit.
03

The MUTCD shall not apply to the following types of facilities:

A. Roadways within private gated properties where access to the general public is restricted at
all times;
B. Grade crossings of privately-owned roadways with railroads; andC. Parking areas, including the driving aisles within those parking areas, that are either publicly or
privately owned.
Support:04
The policies and procedures of the Federal Highway Administration (FHWA) to obtain basic uniformity of
traffic control devices are as described in 23 CFR 655, Subpart F.
05
Section 15-116 of the UVC (see Section 1A.06) states, “No person shall install or maintain in any area ofprivate property used by the public any sign, signal, marking, or other device intended to regulate, warn, or guidetraffic unless it conforms with the State manual and specifications adopted under Section 15-104.” Adoption by
agencies of such a provision through statute or ordinance can help maintain the integrity of official traffic control
devices and provide continuity of uniformity at locations that are not subject to the provisions of this Manual.

Section 1B.02 State Adoption and Conformance

Support:01
All States have officially adopted the National MUTCD either in its entirety, with supplemental provisions, or
as a separate published document. The National MUTCD has also been adopted by the National Park Service, theU.S. Forest Service, the U.S. Military Command, the Bureau of Indian Affairs, the Bureau of Land Management,
and the U.S. Fish and Wildlife Service.
Standard:
02
States or other Federal agencies that have their own MUTCDs or Supplements shall revise these
MUTCDs or Supplements to be in substantial conformance with changes to the National MUTCD within 2
years of the effective date of the Final Rule for the changes [23 CFR 655.603(b)(3)]. Substantial conformanceof such State or other Federal agency MUTCDs or Supplements shall be as defined in 23 CFR 655.603(b)(1).
03
For the purposes of Paragraph 2 of this Section, policies, directives, specifications, standard drawings,
or similar documents that are issued by an agency and that change or modify Standard, Guidance, or
Option provisions in this Manual shall be considered as supplements to the MUTCD and shall also be
revised to be in substantial conformance with the National MUTCD.

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Section 1B.03 Compliance of Devices

Standard:
The U.S. Secretary of Transportation, under authority granted by the Highway Safety Act of 1966,
decreed that traffic control devices on all streets and highways open to public travel in accordance with
23 U.S.C. 109(d) and 402(a) in each State shall be in substantial conformance with the Standards issued
or endorsed by the FHWA.
Support:02
23 CFR 655.603 also requires traffic control devices on all streets, highways, bikeways, and site roadways
open to public travel in each State be in substantial conformance with standards issued or endorsed by the Federal
Highway Administrator.
Standard:
03
After the effective date of a new edition of the MUTCD or a revision thereto, or after the adoption
thereof by the State, whichever occurs later, new or reconstructed devices installed shall comply with the
new edition or revision, as required by 23 CFR 655.603.
04
In cases involving Federal-aid projects for new construction, reconstruction, resurfacing, restoration,or rehabilitation of a facility to which this Manual applies, the traffic control devices installed (temporary
or permanent) shall comply with the most recent edition of the National MUTCD before that highway is
opened or re-opened to the public for unrestricted travel [23 CFR 655.603(d)(2) and (d)(3)].
05
Unless a particular device is no longer serviceable (see definition in Section 1C.02), non-compliant
devices on existing highways and bikeways shall be brought into compliance with the current edition of
the National MUTCD as part of the systematic upgrading of substandard traffic control devices (andinstallation of new required traffic control devices) required pursuant to the Highway Safety Program,
23 U.S.C. §402(a).
Support:
06
The FHWA has the authority to establish other target compliance dates for implementation of particularchanges to the MUTCD [23 CFR 655.603(d)(1)].
Standard:
07
The target compliance dates established by the FHWA shall be as shown in Table 1B-1.
08
Design, application, and placement of traffic control devices other than those adopted in this Manual
shall be prohibited unless the provisions of Sections 1B.04 through 1B.08 are followed regarding official
interpretations, experiments, changes to the MUTCD, and interim approvals granted by the FHWA.
Support:09
Many of the provisions in this Manual that are explicitly prohibitive have been included to address practices
that have been shown to be ineffective, unsafe, or inconsistent with uniformity. A provision of mandatory or
recommended practice represents the accepted and established practice that promotes uniformity and consistency.
The absence of a provision in this Manual that explicitly prohibits a particular practice, use, design, application,
operation, or other aspect of a traffic control device does not, in itself, constitute acceptability or permission to use
the device in a manner not provided for in this Manual.
01

Table 1B-1. Target Compliance Dates Established by the FHWA
MUTCD
Section(s)Subject Area

2B.64

Weight Limit Signs

Paragraph 14 - requirement for additional Weight Limit signwith the advisory distance or directional legend in advance of
applicable section of highway or structure

5 years from the effective dateof this edition of the MUTCD

2C.25

Low Clearance
Signs (W12-2)

Paragraph 1 - Required posting of the Low Clearance Advance(W12-2) sign in advance of the structure

5 years from the effective dateof this edition of the MUTCD

2C.25

Low Clearance
Signs (W12-2a,
W12-2b)Paragraph 8 - Recommended posting of Low Clearance Overhead(W12-2a or 12-2b) signs on an arch or other structure under which
the clearance varies greatly

5 years from the effective dateof this edition of the MUTCD

3A.05

Maintaining
Minimum
Retroreflectivity

Implementation and continued use of a method that is designed
to maintain retroreflectivity of longitudinal pavement markings(see Paragraph 1 of Section 3A.05)

September 6, 2026

8B.16

High-Profile
Grade Crossings

Paragraphs 3 and 7 - Recommended installation of Low Ground
Clearance and/or Vehicle Exclusion signs and detour signs forvehicles with low ground clearances that might hang up on highprofile grade crossings at locations with a known history

5 years from the effective dateof this edition of the MUTCD

8D.09
through
8D.12

Highway Traffic
Signals at or Near
Grade Crossings

Assessment and determination of appropriate treatment toachieve compliance (preemption, movement prohibition,
pre-signals, queue cutter signals)

10 years from the effective
date of this editionof the MUTCD

December 2023

Specific Provision

Compliance Date

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MUTCD 11th Edition

Guidance:
Agencies should contact the FHWA when considering employing a practice or application that is not
explicitly addressed in this Manual to ensure continued compliance with the provisions in this Manual.
Support:11
The FHWA reviews and interprets the provisions in this Manual for agencies on an as-needed basis, which canlead to the issuance of official interpretations (see Section 1B.04), or interim approvals (see Section 1B.07).
Standard:
12
A non-compliant traffic control device that is being replaced or refurbished because it is damaged,
missing, or no longer serviceable (see definition in Section 1C.02) for any reason shall be replaced witha compliant device, except as provided for in Paragraph 13 of this Section.
Option:13
A non-compliant traffic control device may be replaced in kind when engineering judgment indicates it ismore appropriate because:
A. One compliant device in the midst of a series of adjacent non-compliant devices would be confusing toroad users, and/or
B. The schedule for replacement of the whole series of non-compliant devices will result in achieving timely
compliance with the MUTCD.
10

Section 1B.04 Interpretations

Support:The FHWA issues authoritative interpretations of this Manual when necessary to provide clarity in response tounique situations for device application or general requests for clarification of a provision.
02
An interpretation includes a consideration of the application and operation of standard traffic control devices,
the official meanings of standard traffic control devices, or the variations from standard device designs and design
requirements.
Guidance:
03
Requests for an interpretation of this Manual should contain the following information:
A. A concise statement of the interpretation being sought;
B. A description of the condition that provoked the need for an interpretation;
C. Any illustration that would be helpful to understand the request; andD. Any supporting research data that is pertinent to the item to be interpreted.
Support:04
Section 1B.08 contains information on submitting a request for interpretation.
01

Section 1B.05 Experimentation

Support:
Requests for experimentation (see Section 1B.08) include consideration of field deployment for the purpose of
testing or evaluating a new traffic control device, its application or manner of use, or a provision not specificallydescribed in this Manual.
Standard:
02
A traffic control device or application that does not comply with the provisions of this Manual shall not
be used on any street, highway, bikeway, or site roadway open to public travel (see definition in Section 1C.02)
without first receiving official approval to experiment from the FHWA’s Office of Transportation Operations.
Support:03
A request for permission to experiment (see Section 1B.08) will be considered only when submitted by the
public agency or toll facility authority responsible for the operation of the road or street on which the experiment is
to take place. For a site roadway open to public travel, the request will be considered only if it is submitted by theprivate owner or official having jurisdiction.
04
A request for experimentation with a novel device or application across multiple jurisdictions as a single
experiment with a common hypothesis, evaluation plan, and evaluation team will be considered when submitted
jointly by all the authorities responsible for operation of the roads or streets on which the experiment is to takeplace. Similarly, a request to add experimental sites to an experimentation approved for another jurisdiction will
be considered when submitted jointly by the all the authorities for operation of the roads or streets on which theexperiment is then to take place.
05
Manufacturers or inventors of novel devices are encouraged to engage the services of a qualified trafficengineer or other professional who is versed in traffic control devices. Early engagement during the concept anddevelopment processes will help ensure the efficacy of the device with regard to human factors, operational, safety,
and other considerations prior to an agency requesting experimentation.
01

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Page 7

In some cases, an off-roadway closed-course or laboratory study might be required before a request forexperimentation can be considered. The purpose of such a study is to determine whether testing the experimental
device or application in an open-road setting could result in an undue safety risk.
Guidance:07
Before requesting permission to experiment with a new device or application, an owner of a site roadway
open to public travel should first check for any laws, regulations, and/or directives covering the application of the
MUTCD that might apply.
Option:08
An agency may request a preliminary assessment of the viability of a potential request for experimentation bysubmitting an abstract that briefly describes the experimental concept.
Support:09
A diagram indicating the process for requesting and conducting experimentations with traffic control devices
is shown in Figure 1B-1.
06

Figure 1B-1. Process for Requesting and Conducting
Experimentations for New Traffic Control Devices
Requesting jurisdiction
submits request to
FHWA

FHWA Review

No
Approved?

Requesting jurisdiction
responds to questions
raised by FHWA

Yes

Requesting jurisdiction
installs experimental
traffic control device

Requesting jurisdiction
provides semi-annual
reports to FHWA
Division & HQ

Evaluate
experimental traffic
control device

Requesting jurisdiction
provides FHWA acopy of final report

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Sect. 1B.05

Page 8MUTCD 11th Edition

Standard:
The request for permission to experiment shall contain the following:
A. A statement indicating the nature of the problem and a hypothesis establishing the premise of
the experiment.
B. A description of the proposed change to the traffic control device or application of the traffic control
device, including the manner in which it deviates from the provisions of this Manual, and how it isexpected to be an improvement over existing provisions.
C. Illustrations that would help to explain the traffic control device or use of the traffic control device.
D. Any supporting data explaining how the traffic control device was developed, including if it has beentested, in what ways it was found to be adequate or inadequate, and how this choice of device orapplication was derived.
E. Comparison of the proposed device to other compliant devices or treatments, either individually orin combination, that address the same condition, if applicable.
F. A legally-binding statement that the experimental device or application is in the public domain, in
accordance with Paragraph 16 of this Section.
G. The time period and location(s) of the experiment.
H. Control sites for comparison purposes or justification for not using control sites.
I. A detailed research and evaluation plan that provides for close monitoring of the experimentation,
throughout all stages of its field implementation. The evaluation plan shall include an appropriate
evaluation methodology, such as before and after analysis, or other appropriate methodology as wellas quantitative data describing the performance of the experimental device.
J. An agreement to provide semi-annual progress reports for the duration of the experimentation,in accordance with the schedule provided in Paragraph 12 of this Section, and an agreement toprovide a report of the final results of the experimentation to the FHWA’s Office of Transportation
Operations within 3 months following completion of the experimentation (see Paragraph 14 ofthis Section). The FHWA’s Office of Transportation Operations shall have the right to terminate
approval of an agency’s experiment if reports are not received in accordance with this schedule.
K. An agreement to restore the site of the experiment to a condition that complies with the provisionsof this Manual within 3 months following the end of the time period of the experiment. Thisagreement shall also provide that the agency sponsoring the experimentation will terminate theexperimentation at any time that it determines that safety concerns are directly or indirectly
attributable to the experimentation and the agency shall provide timely notification to the FHWA’s
Office of Transportation Operations. The FHWA’s Office of Transportation Operations shallhave the right to terminate approval of the experimentation at any time if there is an indicationof safety or operational concerns, or if the terms of the approval are not being adhered to. If, as aresult of the experimentation, a request is made that this Manual be changed to include the device
or application being experimented with, the FHWA’s Office of Transportation Operations will
determine whether the device or application can be permitted to remain in place until an official
rulemaking action has occurred.
11
Where an item in Paragraph 10 of this Section is determined to not be applicable to the type ofexperiment, device, or application, the request shall provide sufficient explanation.
12
The required semi-annual progress reports shall be submitted throughout the course of an approved
experiment in accordance with the following schedule:
A. No later than August 1st for the preceding period of January through June; andB. No later than February 1st for the preceding period of July through December.
13
The experimenting agency shall submit a semi-annual progress report for any approved experimenteven if no work was performed during the previous reporting period. Failure to submit two consecutive
progress reports shall result in termination of the experiment and shall constitute rescission of the FHWA’s
approval to the experimenting agency, requiring restoration of the site(s) to a condition that complies withthe provisions of this Manual within 3 months.
14
The experimenting agency shall submit a final report within 3 months of the conclusion of an approved
experiment. If a final report is not received by the FHWA’s Office of Transportation Operations, and theexperimenting agency fails to notify the FHWA of any mitigating circumstances within 6 months of theend of the approved experimentation period, then the experiment shall be considered terminated and shallconstitute rescission of the FHWA’s approval to the experimenting agency, requiring restoration of thesite(s) to a condition that complies with the provisions of this Manual within 3 months.
10Sect. 1B.05

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Page 9Support:15
Under certain circumstances the FHWA Office of Transportation Operations might allow an experimental
device or device application that has been shown to be effective and without safety concerns to remain in use after
the experiment has ended. This typically would occur if the device or application is actively being considered forinterim approval under the provisions of Section 1B.07.
Standard:
16
A request for experimentation that involves a new traffic control device or a new application of an
existing traffic control device shall include from the agency conducting the experiment, the manufacturer
and/or developer of the device, and the supplier of the device, a legally-binding statement certifying that thetraffic control device is not protected by a patent, trademark, or copyright in accordance with Section 1D.06,
and that the traffic control device is in the public domain and can be used freely in traffic control device
design and application without infringement or claim of trade secret misappropriation. The legally-binding
statement shall also state that the agency conducting the experiment, the manufacturer and/or developerof the device, and the supplier of the device are aware that if patent, trademark, or copyright protection
is established in the future for the device or application, such action will result in its removal from the
MUTCD, cancellation of its interim approval, or cancellation of the authorization for experimentation.
Support:17
For the purpose of the Standard in Paragraph 16 of this Section, traffic control device refers to those aspects ofa sign, signal, marking or other device which regulates, warns, or guides traffic. The limitation on patent, trademark,or copyright protection does not include the legal protection of individual elements of such devices. For example,
manufacturing methods, assembly methods, or individual components of such devices can be protected, whereas
the traffic control device cannot be subject to protection so long as it remains in this Manual. As a further example,
an internal circuit board for an electronic traffic control device can be legally protected, but the electronic traffic
control device itself or its operational function cannot be legally protected by any of the above forms of intellectual
property rights.

Section 1B.06 Changes to the MUTCD

Support:Continuing advances in technology and approaches to traffic safety will produce changes in the highway,
vehicle, and road-user proficiency; therefore, portions of the system of traffic control devices in this Manual will
require updating. It is important to have a procedure for recognizing these developments and for introducing new
ideas and modifications into the system.
02
A change includes consideration of a new device to replace a present standard device, an additional device tobe added to the list of standard devices, or a revision to a traffic control device application or placement criteria.
Guidance:
03
Requests for a change to this Manual (see Section 1B.08) should contain the following information:
A. A statement indicating what change is proposed;
B. Any illustration that would be helpful to understand the request; andC. Any supporting research data that is pertinent to the item to be reviewed.
Support:04
Requests for a change to this Manual will be evaluated to consider the potential safety and operational benefitsof the requested change and be considered for inclusion in a futurefor consideration in the next rulemaking to issue
a new edition or revision of the Manual. A diagram indicating the process for incorporating new traffic control
devices into this Manual is shown in Figure 1B-2.
01

Section 1B.07 Interim Approvals

Support:Interim approval allows for provisional use, pending official rulemaking, of a new traffic control device, arevision to the application or manner of use of an existing traffic control device, or a provision not specificallydescribed in this Manual.
02
The FHWA issues an interim approval by official memorandum signed by the Associate Administrator forOperations and posts this memorandum on the MUTCD Web site.
03
Interim approval allows for the optional use of a traffic control device or application and does not create a
new mandate or recommendation for its use. Interim approval includes conditions that jurisdictions, toll facility
operators, or owners of site roadways open to public travel agree to comply with in order to use the traffic control
device or application until an official rulemaking action has occurred.
01

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Page 10MUTCD 11th Edition

Figure 1B-2. Process for Incorporating
New Traffic Control Devices into the MUTCD
Request for change
based on successful
experimentation(see Figure 1B-1)

Request for change
based on analytical orlaboratory study

FHWA
review

FHWA notifies
requesting partyNONew
or further
experimentation
required?

NO

YES

YES
See
Figure 1B-1
NO

FHWA notifies
requesting party(if any)

Acceptedfor Federal
rulemaking?

Interimapproval? *YESFHWA issues Interim
Approval with technicalconditions for use, andposts on MUTCD website

FHWA develops device
provisions for inclusion in
the next Notice of
Proposed Amendments
FHWA publishes
Notice of Proposed
Amendments inFederal Register

Docket comment
periodJurisdictions apply for
and receive
Interim Approval
FHWA
reviews comments
Jurisdictions deploy
devices under Interim
Approval conditions
FHWA prepares
Final Rule

FHWA publishes
Final RuleNo action required

NO

Final
Rule
different fromInterimApproval?
YES

State manuals must
be in substantial
conformance with the
National MUTCD within
2 years as specified
in 23 CFR 655.603(a)Jurisdictions comply
with Final Ruleprovisions for device*A change request to allow the use of a new traffic control device is considered for Interim Approval when FHWA determines that the change
will have a substantial national safety or operational benefit and that it would not be in the public interest to wait the intervening time period
before the device could otherwise be officially incorporated into the MUTCD through rulemaking.
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The issuance by FHWA of an interim approval might result in the traffic control device or application being
proposed for adoption in the next scheduled rulemaking process to issue a new edition or revision of this Manual.
If the device or application under interim approval is not proposed in the next rulemaking for a new edition orrevision, then a statement of the status of the interim approval, whether it is to be rescinded or remain in effect,
will be included in the Federal Register notice for the rulemaking.
05
Interim approval is considered based on the results of experimentation, and/or results of analytical orlaboratory studies with a traffic control device or application that analytically demonstrates a device effectively
communicates its intended meaning. Interim approval considerations include an assessment of relative risks,benefits, costs, impacts, and other factors.
06
Section 1B.08 contains information on submitting a request for interim approval.
07
Interim approval is ordinarily considered only after published authoritative research and experimentation
sufficiently demonstrate that the device or application provides a significant safety or operational improvement.
Individual experiments by various jurisdictions, without a research report on the overall findings of theexperimental device or application, will not ordinarily qualify for issuance of an interim approval.
08
Interim approval ordinarily is not considered based solely on non-U.S. experience with a new traffic control
device or application. Differences in regulations, enforcement and penalties, and driver licensing requirements,
among other factors, can result in dissimilar road-user behavior. Additionally, due to variations in conventions
for traffic control device design, a non-U.S. traffic control device concept might need to be adapted to U.S.
criteria to ensure consistency with the provisions and principles of this Manual. However, documented non-U.S.
experience can be considered in the development of requests for experimentation (see Section 1B.05) and within
the evaluation plan for traffic control device research.
Standard:
09
A jurisdiction, toll facility operator, or owner of a site roadway open to public travel that desires to use
a traffic control device or application for which FHWA has issued an interim approval shall request andreceive permission from FHWA in writing prior to applying the device or application.
10
The request to place a traffic control device or application under an existing interim approval shallcontain the following:
A. A description of where the device or application will be used, such as a list of specific locations or
highway segments or types of situations, or a statement of the intent to use the device or application
jurisdiction-wide;
B. An agreement to abide by the specific conditions for use of the device or application as contained in
the FHWA’s interim approval memorandum;
C. An agreement to maintain and continually update a list of locations where the device or application
has been installed; andD. An agreement to:
1. Restore the site(s) of the interim approval to a condition that complies with the provisions in thisManual within 3 months following the issuance of a final rule on this traffic control device orapplication; and2. Terminate use of the device or application installed under the interim approval at any timethat it determines that safety concerns are directly or indirectly attributable to the device
or application. The FHWA’s Office of Transportation Operations shall have the right toterminate the interim approval at any time if there is an indication of safety, operational, orother concerns.
Option:11
A State may submit a request for permission to use a device or application under an existing interim approval
for all jurisdictions in that State, as long as the request contains the information required in Paragraph 9 ofthis Section.
Standard:
12
A jurisdiction, toll facility operator, or owner of a site roadway open to public travel that elects to use
a device or application under a statewide interim approval shall inform the State of its use of the device orapplication.
13
Under a statewide interim approval, the respective jurisdictions, toll facility operators, and owners ofsite roadways open to public travel shall maintain and continually update a record of all locations on theirroads where the device or application is implemented (see Item C of Paragraph 9 of this Section) and shallfurnish this information to the State.
04

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Page 12MUTCD 11th Edition

Section 1B.08 Requesting Official Interpretations, Experiments, Changes to the MUTCD, orInterim Approvals

Guidance:
A local jurisdiction, toll facility operator, or owner of a site roadway open to public travel that is requesting
permission to experiment or permission to use a device or application under an existing interim approval should
first check for any State laws, regulations, and/or directives covering the application of the MUTCD provisions
that might apply.
Standard:
02
Except as provided in Paragraph 3 of this Section, requests for an interpretation, permission
to experiment, a change to the MUTCD, granting of an interim approval, or permission to use an
existing interim approval shall be submitted electronically to the Federal Highway Administration(FHWA), Office of Transportation Operations, MUTCD team, at the following e-mail address:
MUTCDofficialrequest@dot.gov.
Option:03
If electronic submittal is not possible, requests for an interpretation, permission to experiment, a change to the
MUTCD, granting of an interim approval, or permission to use an existing interim approval may instead be mailed
to the Office of Transportation Operations, HOTO-1, Federal Highway Administration, 1200 New Jersey Avenue,
SE, Washington, DC 20590.
Support:04
Communications regarding other MUTCD matters that are not related to official requests will receive quicker
attention if they are submitted electronically to the MUTCD Team Leader or to the appropriate individual
MUTCD technical lead team member. Their e-mail addresses are available through the links contained on the“MUTCD Team” page on the MUTCD Web site at http://mutcd.fhwa.dot.gov/team.htm.
05
For additional information concerning interpretations, experimentation, changes, or interim approvals, visit the
MUTCD Web site at http://mutcd.fhwa.dot.gov.
01

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Page 13

CHAPTER 1C. DEFINITIONS, ACRONYMS, AND
ABBREVIATIONS USED IN THIS MANUAL

Section 1C.01 Definitions of Headings Used in this Manual

Standard:
01
When used in this Manual, the text headings of Standard, Guidance, Option, and Support shall bedefined as follows:
A. Standard—a statement of required, mandatory, or specifically prohibitive practice regarding a
traffic control device. In limited, location-specific cases, the results of a documented engineering
study (see Section 1D.03) might indicate a deviation from one or more requirements of a Standard
provision to be appropriate. All Standard statements are labeled, and the text appears in bold
type. The verb “shall” is typically used. The verbs “should” and “may” are not used in Standard
statements. Standard statements are sometimes modified by Option statements.
B. Guidance—a statement of recommended practice in typical situations, with deviations allowed
if engineering judgment or engineering study (see Section 1D.03) indicates the deviation to beappropriate. All Guidance statements are labeled, and the text appears in unbold italic type. The
verb “should” is typically used. The verbs “shall” and “may” are not used in Guidance statements.
Guidance statements are sometimes modified by Option statements.
C. Option—a statement of practice that is a permissive condition and carries no requirement or
recommendation. Option statements sometimes contain allowable modifications to a Standard or
Guidance statement. All Option statements are labeled, and the text appears in unbold type. The
verb “may” is typically used. The verbs “shall” and “should” are not used in Option statements.
D. Support—an informational statement that does not convey any degree of mandate, recommendation,authorization, prohibition, or enforceable condition. Support statements are labeled, and the text
appears in unbold type. The verbs “shall,” “should,” and “may” are not used in Support statements.

Section 1C.02 Definitions of Words and Phrases Used in this Manual

Standard:
01
Unless otherwise defined in this Section, or in other Parts of this Manual, words or phrases shall havethe meaning(s) as defined in the “Uniform Vehicle Code,” “AASHTO Transportation Glossary (Highway
Definitions),” or other appropriate publications.
02
Where a term that is defined in this Section or elsewhere in this Manual has a different definition inanother resource or in common use, the definition herein shall govern for purposes of the applicability ofthe provisions of this Manual.
03
The following words and phrases, when used in this Manual, shall have the following meanings:
1. Accessible Pedestrian Signal—a device that communicates information about pedestriansignal timing in a non-visual format such as audible tones and/or speech messages andvibrating surfaces.
2. Accessible Pedestrian Signal Detector—a device designated to assist the pedestrian who has
vision or physical disabilities in activating the pedestrian phase.
3. Active Grade Crossing—a grade crossing equipped with automatic traffic control devices,such as flashing-light signals, gates, and/or traffic control signals, that are activated upon thedetection of approaching rail traffic.
4. Actuated—a type of traffic control signal operation in which some or all signal phases areoperated on the basis of actuation.
5. Actuation—initiation of, a change in, or an extension of a traffic signal phase or a sign legend
through the operation of any type of detector.
6. Advance Preemption—the notification of approaching rail traffic that is forwarded to thehighway traffic signal controller unit or assembly by the railroad or light rail transit equipmentin advance of the activation of the railroad or light rail transit warning devices.
7.
Advance Preemption Time—the period of time that is the difference between the required
maximum highway traffic signal preemption time and the activation of the railroad or light railtransit warning devices.
8. Advisory Speed—a recommended speed for all vehicles operating on a section of highway andbased on the highway design, operating characteristics, and conditions.
9.
Agency—an organization with the responsibility for providing, maintaining, and/or operating apublic or private road system.
10. Alley—a street or highway intended to provide access to the rear or side of lots or buildings inurban areas and not intended for the purpose of through vehicular traffic.
December 2023

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Page 14

11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.

22.
23.
24.
25.

Sect. 1C.02

MUTCD 11th Edition

Annual Average Daily Traffic (AADT)—the total volume of traffic passing a point or segmentof a highway facility in both directions for one year divided by the number of days in the year.
Normally, periodic daily traffic volumes are adjusted for hours of the day counted, days of theweek, and seasons of the year to arrive at annual average daily traffic.
Application—in regard to a traffic control device, the act of deciding to use a device, generally
or at a particular location for a particular condition.
Approach—all lanes of traffic moving toward an intersection or a midblock location from one
direction, including any adjacent parking lane(s).
Arterial Highway (Street)—a general term denoting a highway primarily used by throughtraffic, usually on a continuous route or a highway designated as part of an arterial system.
Automated Vehicle—see Driving Automation System.
Automatic Lane—see Exact Change Lane within the definition of Toll Collection.
Average Daily Traffic (ADT)—the average 24 hour volume, being the total volume during astated period divided by the number of days in that period. Normally, this would be periodic
daily traffic volumes over several days, not adjusted for days of the week or seasons of the year.
Average Day—a day representing traffic volumes normally and repeatedly found at a location,
typically a weekday when volumes are influenced by employment or a weekend day whenvolumes are influenced by entertainment or recreation.
Backplate—see Signal Backplate.
Barrier-Separated Lane—a preferential lane or other special purpose lane that is separated
from the adjacent general-purpose lane(s) by a physical barrier.
Beacon—a highway traffic signal with one or more signal indications that operates in a flashingmode. Types of beacons include:(a) Emergency-Vehicle Hybrid Beacon—a special type of beacon (see Hybrid Beacon).
(b) Intersection Control Beacon—a beacon used only at an intersection to control two or more
directions of travel.
(c) Pedestrian Hybrid Beacon—a special type of beacon (see Hybrid Beacon).
(d) Rectangular Rapid-Flashing Beacon (RRFB)—a pedestrian-activated and/or bicycleactivated device comprising two horizontally arranged, rapidly flashed, rectangular-shaped
yellow indications that is used to provide supplemental emphasis for a pedestrian, school, ortrail crossing warning sign at a marked crosswalk across an uncontrolled approach.
(e) Speed Limit Sign Beacon—a beacon used only to supplement a SPEED LIMIT sign.
(f) Stop Beacon—a beacon used only to supplement a STOP sign, a DO NOT ENTER sign, or a
WRONG WAY sign.
(g) Warning Beacon—a beacon used only to supplement an appropriate warning or regulatory
sign or marker.
Bicycle—a pedal-powered vehicle upon which the human operator sits.
Bicycle Box—a designated area on the approach to a signalized intersection, between an advancemotorist stop line and the crosswalk or intersection, intended to provide bicyclists a visible place
to wait in front of stopped motorists during the red signal phase.
Bicycle Facilities—a general term denoting improvements and provisions that accommodate
or encourage bicycling, including parking and storage facilities, and shared roadways not
specifically defined for bicycle use.
Bicycle Lane—a portion of a roadway that has been designated for preferential or exclusive use
by bicyclists. A typical bicycle lane is delineated from the adjacent general-purpose lane(s) bylongitudinal pavement markings and bicycle lane symbol or word markings and, if used, signs.
Other types of bicycle lanes include:(a) Buffer-Separated Bicycle Lane—a bicycle lane that is separated from the adjacent generalpurpose lane(s) by a pattern of standard longitudinal pavement markings that is wider thana normal or wide lane line marking.
(b) Counter-Flow Bicycle Lane—a one-directional bicycle lane that provides a lawful path oftravel for bicycles in the opposite direction from general traffic on a roadway that allows
general traffic to travel in only one direction. Counter-flow bicycle lanes are designated by
the traffic control devices used for other bicycle lanes.
(c) Separated Bicycle Lane—an exclusive facility for bicyclists that is located within or directly
adjacent to the roadway and that is physically separated from motor vehicle traffic with avertical element. Separated bicycle lanes are differentiated from other bicycle lanes by avertical element.
December 2023

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26. Bicycle Signal Face—a signal face that displays only bicycle symbol signal indications, that
exclusively controls a bicycle movement from a designated bicycle lane or from a separate
facility such as a shared-use path, and that displays signal indications that are applicable only tothe bicycle movement.
27. Bicycle Symbol Signal Indication—a red, yellow, or green signal indication that displays abicycle symbol rather than a circular or arrow indication.
28. Bikeway—a generic term for any road, street, path, or way that in some manner is specificallydesignated for bicycle travel, regardless of whether such facilities are designated for the
exclusive use of bicycles or are to be shared with other transportation modes.
29. Blank-Out Sign—a sign that displays a single predetermined message only when activated.
When not activated, the sign legend is not visible.
30. Buffer-Separated Lane—a preferential lane or other special purpose lane that is separated fromthe adjacent general-purpose lane(s) by a pattern of standard longitudinal pavement markingsthat is wider than a normal or wide lane line marking. The buffer area might include rumble
strips, textured pavement, or channelizing devices such as tubular markers or traversable curbs,
but does not include a physical barrier.
31. Business Identification Sign Panel—a panel containing a word legend or logo used to identify abusiness on a Specific Service sign.
32. Busway—a traveled way that is used exclusively by buses.
33. Cantilevered Signal Structure—a structure, also referred to as a mast arm, that is rigidly
attached to a vertical pole and is used to provide overhead support of highway traffic signal
faces or grade crossing signal units.
34. Center Line Markings—the yellow pavement marking line(s) that delineates the separation of
traffic lanes that have opposite directions of travel on a roadway. These markings need not be at
the geometrical center of the pavement.
35. Changeable Message Sign—a sign that is capable of displaying more than one message (one ofwhich might be a “blank” display), changeable manually, by remote control, or by automatic
control. Electronic-display changeable message signs are referred to as Dynamic Message
Signs in the National Intelligent Transportation Systems (ITS) Architecture and are referred
to as Variable Message Signs in the National Electrical Manufacturers Association (NEMA)
standards publication.
36. Channelizing Line—a solid wide or double white line marking used to form islands wheretraffic in the same direction of travel is permitted on both sides of the island.
37. Circular Intersection—an intersection that has an island, generally circular in design, locatedin the center of the intersection where traffic passes to the right of the island. Circularintersections include roundabouts, rotaries, and traffic circles.
38. Circulatory Roadway—the roadway within a circular intersection on which traffic travels in acounterclockwise direction around an island in the center of the circular intersection.
39. Clear Storage Distance—when used in Part 8, the distance available for vehicle storage
measured between 6 feet from the rail nearest the intersection to the intersection stop line or thenormal stopping point on the highway. At skewed grade crossings and intersections, the 6-footdistance shall be measured perpendicular to the nearest rail either along the center line or edge
line of the highway, as appropriate, to obtain the shorter distance. Where exit gates are used, thedistance available for vehicle storage is measured from the point where the rear of the vehicle
would be clear of the exit gate arm. In cases where the exit gate arm is parallel to the track(s)and is not perpendicular to the highway, the distance is measured either along the center line oredge line of the highway, as appropriate, to obtain the shorter distance.
40. Clear Zone—the total roadside border area, starting at the edge of the traveled way, that isavailable for an errant driver to stop or regain control of a vehicle. This area might consist of ashoulder, a recoverable slope, and/or a non-recoverable, traversable slope with a clear run-out
area at its toe.
41. Collector Highway—a term denoting a highway that in rural areas connects small towns
and local highways to arterial highways, and in urban areas provides land access and traffic
circulation within residential, commercial, and business areas and connects local highways tothe arterial highways.
42. Conflict Monitor—a device used to detect and respond to improper or conflicting signal
indications and improper operating voltages in a traffic controller assembly.
43. Constant Warning Time Detection—a means of detecting rail traffic that provides relatively
uniform warning time for the approach of through rail traffic that is not accelerating or
decelerating after being detected.
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MUTCD 11th Edition

44. Contiguous Lane—a lane, preferential or otherwise, that is separated from the adjacent lane(s)only by a normal or wide lane line marking.
45. Controller Assembly—a complete electrical device mounted in a cabinet for controlling theoperation of a highway traffic signal.
46. Controller Unit—that part of a controller assembly that is devoted to the selection and timing of
the display of signal indications.
47. Conventional Road—a street or highway other than an expressway or freeway.
48. Counter-Flow Lane—a lane operating in a direction opposite to the normal flow of traffic
designated for peak direction of travel during at least a portion of the day. Counter-flow lanes
are usually separated from the off-peak direction lanes by tubular markers or other flexible
channelizing devices, temporary lane separators, or movable or permanent barrier.
49. Crashworthy—the ability of a roadside safety hardware device or appurtenance to minimizerisks to vehicle occupants by allowing a vehicle impacting the appurtenance to be slowed before
stopping, redirected, or to continue without significant resistance. Section 1D.11 contains
additional information about crashworthiness.
50. Crosswalk—(a) that part of a roadway at an intersection included within the connections of thelateral lines of the sidewalks on opposite sides of the highway measured from the curbs or in theabsence of curbs, from the edges of the traversable roadway, and in the absence of a sidewalk on
one side of the roadway, the part of a roadway included within the extension of the lateral linesof the sidewalk at right angles to the center line; (b) any portion of a roadway at an intersection
or elsewhere distinctly indicated as a pedestrian crossing by pavement marking lines on thesurface, which might be supplemented by contrasting pavement texture, style, or color.
51. Crosswalk Lines—white pavement marking lines that identify a crosswalk.
52. Cycle Length—the time required for one complete sequence of signal indications.
53. Dark Mode—the lack of all signal indications at a signalized location. The dark mode is mostcommonly associated with power failures, ramp meters, hybrid beacons, beacons, and some
movable bridge signals.
54. Dedicated Lane—A lane on a freeway or expressway that provides access to: (a) either an exit
lane or the mainline, but not both, at a freeway or expressway exit, or (b) only one roadway at a
freeway or expressway split.
55. Delineator—a retroreflective device mounted at the side of the roadway in a series to indicate thealignment of the roadway, especially at night or in adverse weather.
56. Design Vehicle—the longest vehicle permitted by statute of the road authority (State or other) onthat roadway.
57. Designated Bicycle Route—a system of bikeways designated by the jurisdiction having authority
with appropriate directional and informational route signs, with or without specific bicycle
route numbers.
58. Detectable—having a continuous edge within 6 inches of the surface so that pedestrians withvision disabilities can sense its presence and receive usable guidance information.
59. Detector—a device used for determining the presence or passage of motor vehicles, bicycles, orpedestrians.
60. Detection Plate—a smooth continuous plate used on pedestrian channelizing devices tofacilitate the use of low-vision canes for pedestrians with vision disabilities. The bottom edgeof the detection plate shall be no more than 2 inches above the walkway and the top edge of thedetection plate shall be at least 8 inches above the walkway. The detection plate shall share thesame vertical plane as the hand trailing edge of the pedestrian channelizing device.
61. Diagnostic Team—a group of knowledgeable representatives of the parties of interest in a grade
crossing or group of grade crossings (see 23 CFR Part 646.204).
62. Downstream—a term that refers to a location that is encountered by traffic subsequent to an
upstream location as it flows in an “upstream to downstream” direction. For example, “thedownstream end of a lane line separating the turn lane from a through lane on the approach to
an intersection” is the end of the lane line that is closest to the intersection.
63. Driveway—an access from a roadway to a building, site, or abutting property.
64. Driving Aisle—circulation area for motor vehicles within a parking area, typically between rowsof parking spaces. Driving aisles provide one-way or two-way travel. Driving aisles are exemptedfrom compliance with MUTCD provisions.
65. Driving Automation System—technology that automates some or all aspects of the driving
task to assist or replace the human vehicle operator. Section 5A.03 contains descriptions of theautomation levels.
66. Dropped Lane—see Lane Drop.
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MUTCD 11th Edition

67.
68.
69.
70.
71.
72.
73.
74.
75.
76.

77.

78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
December 2023

Page 17Dual-Arrow Signal Section—a type of signal section designed to include both a yellow arrow
and a green arrow.
Dynamic Envelope—the clearance required for light rail transit traffic or a train and its
cargo overhang due to any combination of loading, lateral motion, or suspension failure(see Figure 8C-3).
Dynamic Exit Gate Operating Mode—a mode of operation where the exit gate operation isbased on the presence of vehicles within the minimum track clearance distance.
Dynamic Message Sign—see Changeable Message Sign.
Edge Line Markings—white or yellow pavement marking lines that delineate the right or leftedge(s) of a traveled way.
Electronic Toll Collection (ETC) Account Only Lane—a non-attended toll lane that is restricted
to use only by vehicles with a registered toll payment account.
Emergency-Vehicle Hybrid Beacon—see Hybrid Beacon.
Emergency-Vehicle Traffic Control Signal—see Highway Traffic Signal.
Engineer—see Professional Engineer.
Engineering Judgment—the evaluation of available pertinent information including, but
not limited to, the safety and operational efficiency of all road users, and the application of
appropriate principles, provisions, and practices as contained in this Manual and other sources,
for the purpose of deciding upon the design (see Section 1D.03), use, installation, or operationof a traffic control device. Engineering judgment shall be exercised by a professional engineer(see definition in this Section) with appropriate traffic engineering expertise, or by an individual
working under the supervision of such an engineer, through the application of procedures andcriteria established by the engineer. Documentation of engineering judgment is not required.
Engineering Study—the analysis and evaluation of available pertinent information including,but not limited to, the safety and operational efficiency of all road users, and the application of
appropriate principles, provisions, and practices as contained in this Manual and other sources,
for the purpose of deciding upon the design (see Section 1D.03), use, installation, or operationof a traffic control device. An engineering study shall be performed by a professional engineer(see definition in this Section) with appropriate traffic engineering expertise, or by an individual
working under the supervision of such an engineer, through the application of procedures andcriteria established by the engineer. An engineering study shall be documented in writing.
Entrance Gate—an automatic gate that can be lowered across the lanes approaching a grade
crossing to block road users from entering the grade crossing.
Exclusive Alignment—a light rail transit track(s) or a bus rapid transit busway that is gradeseparated or protected by a fence or traffic barrier. No grade crossings exist along the track(s)or busway. Motor vehicles, bicycles, and pedestrians are prohibited within the right-of-way.
Subways and elevated structures are included within this definition.
Exit Gate—an automatic gate that can be lowered across the lanes departing a grade crossing
to block road users from entering the grade crossing by driving in the opposing traffic lanes.
Exit Gate Clearance Time—for Four-Quadrant Gate systems at grade crossings, the amountof time provided to delay the descent of the exit gate arm(s) after entrance gate arm(s) begin
to descend.
Exit Gate Operating Mode—for Four-Quadrant Gate systems at grade crossings, the mode ofcontrol used to govern the operation of the exit gate arms.
Expressway—a divided highway with partial control of access.
Fail-Safe—when used in Part 8, a railroad signal design philosophy applied to a system ordevice such that the result of a hardware failure or the effect of a software error shall either
prohibit the system or device from assuming or maintaining an unsafe state or shall cause thesystem or device to assume a state that is known to be safe.
Flagger—a person who actively controls the flow of vehicular traffic into and/or througha temporary traffic control zone using hand-signaling devices or an Automated Flagger
Assistance Device (AFAD).
Flasher—a device used to turn highway traffic signal indications on and off at a repetitive rateof approximately once per second.
Flashing—an operation in which a light source, such as a traffic signal indication or LEDs in asign, is turned on and off repetitively.
Flashing-Light Signals—a warning device consisting of two red signal indications arranged
horizontally that are activated to flash alternately when rail traffic is approaching or present
at a grade crossing.
Flashing Mode—a mode of operation in which at least one traffic signal indication in eachvehicular signal face of a highway traffic signal is turned on and off repetitively.

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MUTCD 11th Edition

90. Four-Quadrant Gate System—an exit gate system that includes entrance and exit gates that
control and block road users on all lanes entering and exiting the grade crossing.
91. Freeway—a divided highway with full control of access.
92. Full-Actuated—a type of traffic control signal operation in which all signal phases function on
the basis of actuation.
93. Gate—an automatically-operated or manually-operated traffic control device that is used tophysically obstruct road users such that they are discouraged from proceeding past a particularpoint on a roadway or pathway, or such that they are discouraged from entering a particular
grade crossing, ramp, lane, roadway, or facility.
94. General-Purpose Lane—a highway lane or set of lanes, other than a Managed Lane (seedefinition in this Section) or a Preferential Lane (see definition in this Section), that all or mostof the traffic that is allowed on that highway is also allowed to use. Certain classes of vehicles,
such as commercial vehicles or vehicles exceeding a certain weight or size, might be prohibitedfrom using one or more of the general-purpose lanes. A general-purpose lane might also be
restricted to certain uses, such as passing or turning or as an auxiliary lane.
95. Gore Area—see Physical Gore and Theoretical Gore.
96. Grade Crossing—the general area where a highway and a railroad and/or light rail transit routecross at the same level, within which are included the tracks, highway, and traffic control devices
for traffic traversing that area.
97. Grade Crossing Warning System—the flashing-light signals, with or without automatic gates,
together with the necessary control equipment used to inform road users of the approach orpresence of rail traffic at a grade crossing.
98. Guide Sign—a sign that shows route designations, highway names, destinations, directions,distances, services, points of interest, or other geographical, recreational, or cultural
information.
99. High-Occupancy Vehicle (HOV)—a motor vehicle carrying at least two (or more than two if
the signs for a specific roadway indicate a higher minimum occupancy requirement) persons,
including carpools, vanpools, and buses.
100. Highway—a general term for denoting a public way for purposes of travel by vehicles andvulnerable road users, including the entire area within the right-of-way.
101. Highway-Light Rail Transit Grade Crossing—the general area where a highway and a lightrail transit route cross at the same level, within which are included the light rail transit tracks,
highway, and traffic control devices for traffic traversing that area.
102. Highway-Rail Grade Crossing—the general area where a highway and a railroad cross at thesame level, within which are included the railroad tracks, highway, and traffic control devices
for highway traffic traversing that area.
103. Highway Traffic Signal—a power-operated traffic control device by which traffic is warned
or directed to take some specific action. These devices do not include power-operated signs(except as provided in Chapters 4S and 4T), steadily illuminated raised pavement markers,
gates, flashing-light signals (see Section 8D.02), warning lights (see Section 6L.07), or steadyburning electric lamps. Highway traffic signals include:(a) Flashing Beacon—see Beacon.
(b) In-Roadway Warning Lights—a special type of highway traffic signal installed in the
roadway surface to warn road users that they are approaching a condition on or adjacent to
the roadway that might not be readily apparent and might require the road users to reduce
speed and/or come to a stop.
(c) Lane-Use Control Signal—a signal face or comparable display on a full-matrix Changeable
Message Sign (see Chapters 2L and 4T) displaying indications to permit or prohibit the useof specific lanes of a roadway or a shoulder where driving is sometimes permitted, or toindicate the impending prohibition of such use.
(d) Traffic Control Signal (Traffic Signal)—a highway traffic signal placed at intersections,
movable bridges, fire stations, midblock crosswalks, alternating one-way sections of a single
lane road, private driveways, or other locations that require conflicting traffic to be directed
to stop and permitted to proceed in an orderly manner. These devices do not include
pedestrian hybrid beacons (see Chapter 4J) or emergency-vehicle hybrid beacons (seeChapter 4N). Traffic control signals include vehicular signal indications, pedestrian signal
indications, and bicycle symbol signal indications. Special traffic control signals include:(1) Emergency-Vehicle Traffic Control Signal—a traffic control signal that directs all
conflicting traffic to stop in order to permit the driver of an authorized emergency
vehicle to proceed into the roadway or intersection.
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Page 19(2) Movable Bridge Traffic Control Signal—a traffic control signal installed at a movablebridge to notify traffic to stop during periods when the roadway is closed to allow thebridge to open.
(3) Portable Traffic Control Signal—a temporary component of a traffic control signal
on a mobile support with one or more signal faces that is designed so that it can beeasily transported, deployed, or relocated as part of a temporary traffic control signal,or during construction and maintenance as a temporary part of a permanent traffic
control signal installation.
(4) Pre-Signal—traffic control signal faces that are located upstream from a signalizedintersection and are operated in conjunction with the traffic control signal faces
at the downstream signalized intersection in a manner that is designed to keep thearea between the stop line for the upstream traffic control signal faces and the stop
line for the downstream signalized intersection clear of queued vehicles. When usedin conjunction with a grade crossing, the pre-signal is operated for the purpose of
preventing vehicles from queuing within the minimum track clearance distance.
Supplemental near-side traffic control signal faces for the downstream signalizedintersection are not considered to be pre-signals.
(5) Queue Cutter Signal—an independently-controlled traffic control signal (not operated inconjunction with the traffic control signal faces at a downstream signalized intersection)
located at a grade crossing that controls traffic in one direction only on the roadway
for the purpose of keeping the minimum track clearance distance clear of vehicles. The
display of red signal indications is activated from a downstream queue detection system,by time of day, by approaching rail traffic, by an approaching bus on a busway, or by a
combination of any of these methods.
(6) Ramp Control Signal—a traffic control signal installed to control the merging flow of
traffic onto a freeway at an entrance ramp or at a freeway-to-freeway ramp connection.
(7) Temporary Traffic Control Signal—a traffic control signal that is installed for a limited
time period using fixed or portable traffic control signal units.
104. HOV Lane—any preferential lane designated for exclusive use by high-occupancy vehicles for allor part of a day—including a designated lane on a freeway, other highway, street, or independent
roadway on a separate right-of-way.
105. Hybrid Beacon—a special type of beacon that is intentionally placed in a dark mode (noindications displayed) between periods of operation and, when operated, displays both steadyand flashing traffic control signal indications. Hybrid beacons include:(a) Emergency-Vehicle Hybrid Beacon—used to warn and control traffic at an unsignalized
location to assist authorized emergency vehicles in entering or crossing a street or highway.
(b) Pedestrian Hybrid Beacon—used to warn and control traffic at an unsignalized location toassist pedestrians in crossing a street or highway at a marked crosswalk.
106. Identification Marker—a shape, color, and/or pictograph that is used as a visual identifier for a
destination guide signing system of a community wayfinding system or a shared-use path system
for an area.
107. Inherently Low Emission Vehicle (ILEV)—any kind of vehicle that, because of inherent
properties of the fuel system design, will not have significant evaporative emissions, even if its
evaporative emission control system has failed.
108. In-Roadway Warning Lights—see Highway Traffic Signal.
109. Interchange—a system of interconnecting roadways providing for traffic movement between two
or more highways that do not intersect at grade.
110. Interchange Lane Drop—see Lane Drop.
111. Preemption Interconnection—the electrical connection between the railroad or light rail transit
active warning system and the highway traffic signal controller assembly for the purpose ofpreemption.
112. Intermediate Interchange—an interchange with an urban or rural route that is not a major orminor interchange as defined in this Section.
113. Intersection—intersection is defined as follows:(a) The area embraced within the prolongation or connection of the lateral curb lines, or if
none, the lateral boundary lines of the roadways of two highways that join one another at,
or approximately at, right angles, or the area within which vehicles traveling on different
highways that join at any other angle might come into conflict.
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MUTCD 11th Edition(b) The junction of an alley, driveway, or site roadway with a public roadway or highway shallnot constitute an intersection, unless the public roadway or highway at said junction iscontrolled by a traffic control device.
(c) If a highway includes two roadways separated by a median, then every crossing of eachroadway of such divided highway by an intersecting highway shall be a separate intersection
if the opposing left-turn paths cross and there is sufficient interior storage for the design
vehicle (see Figure 2A-5).
(d) At a location controlled by a traffic control signal, regardless of the distance between theseparate intersections as defined in (c) above:(1) If a stop line, yield line, or crosswalk has not been designated on the roadway (within
the median) between the separate intersections, the two intersections and the roadway(median) between them shall be considered as one intersection;(2) Where a stop line, yield line, or crosswalk is designated on the roadway on theintersection approach, the area within the crosswalk and/or beyond the designated stop
line or yield line shall be part of the intersection; and(3) Where a crosswalk is designated on a roadway on the departure from the intersection,
the intersection shall include the area extending to the far side of such crosswalk.
114. Intersection Control Beacon—see Beacon.
115. Interval—the part of a signal cycle during which signal indications do not change.
116. Island—a defined area between traffic lanes for control of vehicular movements, for tollcollection, or for pedestrian or bicyclist refuge. It includes all end protection and approach
treatments. Within an intersection area, a median or an outer separation is considered to be
an island.
117. Jughandle Turn—a left-turn or U-turn that, in conjunction with special geometry, is made byinitially making a right-turn or diverging to the right. With other special geometry, a right-turnor U-turn makes a jughandle turn by initially making a left-turn or diverging to the left.
118. Lane Drop—a through lane that becomes a mandatory turn lane on a conventional roadway,or a through lane that becomes a mandatory exit lane on a freeway or expressway. The endof an acceleration lane and reductions in the number of through lanes that do not involve a
mandatory turn or exit are not considered lane drops.
119. Lane Line Markings—white pavement marking lines that delineate the separation of traffic
lanes that have the same direction of travel on a roadway.
120. Lane Reduction—elimination of a through lane by a gradual narrowing of the travel pavement(taper) through physical construction or pavement markings at which traffic in the lane being
eliminated must merge into the adjacent through lane and continue in the same direction of
travel. A lane reduction can occur outside the influence of an intersection or interchange, orwithin an interchange a short distance downstream of the gore of an exit ramp. Through lanes
that become a mandatory turn or exit are considered lane drops rather than lane reductions.
121. Lane-Use Control Signal—see Highway Traffic Signal.
122. Legend—see Sign Legend.
123. Lens—see Signal Lens.
124. Light Rail Transit Traffic (Light Rail Transit Equipment)—every device in, upon, or by which
any person or property can be transported on light rail transit tracks, including single-unit lightrail transit cars (such as streetcars and trolleys) and assemblies of multiple light rail transit cars
coupled together.
125. Loading Zone—a specially marked, signed or designated area for the loading or unloading ofvehicles (passenger or freight).
126. Locomotive Horn—an air horn, steam whistle, or similar audible warning device (see 49 CFRPart 229.129) mounted on a locomotive or control cab car. The terms “locomotive horn,”“train whistle,” “locomotive whistle,” and “train horn” are used interchangeably in therailroad industry.
127. Logo—a distinctive emblem or trademark that identifies a commercial or non-commercial
business, program, or organization.
128. Longitudinal Markings—pavement markings that are generally placed parallel and adjacent to
the flow of traffic such as lane lines, center lines, edge lines, channelizing lines, and others.
129. Louver—see Signal Louver.
130. Low-Volume Rural Road—A category of paved or unpaved conventional or special-purpose
roadways having an AADT of less than 400 vehicles and lying outside of built-up or urbanizedareas of cities, towns, and communities.
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Page 21131. Major Interchange—an interchange with another freeway or expressway, or an interchangewith a high-volume multi-lane highway, principal urban arterial, or major rural route where theinterchanging traffic is heavy or includes many road users unfamiliar with the area.
132. Major Street—the street normally carrying the higher volume of vehicular traffic.
133. Malfunction Management Unit—see Conflict Monitor.
134. Managed Lane—a highway lane or set of lanes, or a highway facility, for which variable
operational strategies such as direction of travel, tolling, pricing, and/or vehicle type or
occupancy requirements are implemented and managed in real-time in response to changing
conditions. Managed lanes are typically buffer-separated or barrier-separated lanes parallelto the general-purpose lanes of a highway in which access is restricted to designated locations.
There are also some highways on which all lanes are managed.
135. Manual Lane—see Attended Lane within the definition of Toll Collection.
136. Maximum Highway Traffic Signal Preemption Time—the maximum amount of time needed
following initiation of the preemption sequence for the highway traffic signals to complete thetiming of the right-of-way transfer time, queue clearance time, and separation time.
137. Median—the portion of a highway separating opposing directions of the traveled way or thearea between two roadways of a divided highway measured from edge of traveled way to edgeof traveled way. The median excludes turn lanes. The median width might be different between
intersections, interchanges, and at opposite approaches of the same intersection.
138. Minimum Track Clearance Distance—the length along a highway over the track(s) where avehicle could be struck by rail traffic. The minimum track clearance distance is measured froma point upstream from the track(s) on the approach to the grade crossing to a point downstream
from the track(s) on the departure from the grade crossing. The length along the highway
between the two points is the minimum track clearance distance.
139. Minor Interchange—an interchange where traffic is local and very light, such as interchanges
with land service access roads. Where the sum of the exit volumes is estimated to be lower than
100 vehicles per day in the design year, the interchange is classified as local.
140. Minor Street—the street normally carrying the lower volume of vehicular traffic.
141. Mixed-Use Alignment—a light rail transit track(s), a busway, or a bus only lane(s) where thelight rail transit (LRT) or bus rapid transit (BRT) vehicles operate in mixed traffic with all
types of road users. This includes streets, transit malls, and pedestrian malls where the rightof-way is shared. In a mixed-use alignment, the light rail transit or the bus rapid transit traffic
does not have the right-of-way over other road users at grade crossings and intersections. If
the LRT traffic or buses are controlled by traffic control signals or LRT signal faces at anintersection with a roadway, the alignment is considered to be mixed-use even if some of theapproaches to the intersection are used exclusively by LRT traffic or buses.
142. Movable Bridge Resistance Gate—a type of traffic gate, which is located downstream of the
movable bridge warning gate, that provides a physical deterrent to vehicle and/or pedestrian
traffic when placed in the appropriate position.
143. Movable Bridge Signal—see Highway Traffic Signal.
144. Movable Bridge Warning Gate—a type of traffic gate designed to warn, but not primarily toblock, vehicle and/or pedestrian traffic when placed in the appropriate position.
145. Multi-Lane—more than one lane moving in the same direction. A multi-lane street, highway,
or roadway has a basic cross-section comprised of two or more through lanes in one or both
directions. A multi-lane approach has two or more lanes moving toward the intersection,
including turning lanes.
146. Neutral Area—the paved area between the channelizing lines separating an entrance or exit
ramp or a channelized turn lane or channelized entering lane from the adjacent through lane(s).
147. Object Marker—a device used to mark obstructions within or adjacent to the roadway.
148. Occupancy Requirement—any restriction that regulates the use of a facility or one or morelanes of a facility for any period of the day based on a specified minimum number of persons ina vehicle.
149. Occupant—a person driving or riding in a car, truck, bus, or other vehicle.
150. On-Street Parking—parking within or along, and accessed directly from, a public roadway or asite roadway open to public travel.
151. Open-Road ETC Lane—a non-attended lane that is designed to allow toll payments to beelectronically collected from vehicles traveling at normal highway speeds. Open-Road ETC
lanes are typically physically separated from the toll plaza, often following the alignment of themainline lanes, with toll plaza lanes for cash toll payments being on a different alignment after
diverging from the mainline lanes or a subset thereof.
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152. Open-Road Tolling Point—the location along an Open-Road ETC lane at which roadsideor overhead detection and receiving equipment are placed and vehicles are electronicallyassessed a toll.
153. Opposing Traffic—vehicles that are traveling in the opposite direction. At an intersection,
vehicles entering from an approach that is approximately straight ahead would be considered
to be opposing traffic, but vehicles entering from approaches on the left or right would beconsidered to be conflicting traffic rather than opposing traffic.
154. Option Lane—A lane on a freeway, expressway, or conventional road multi-lane exit or multilane split that widens on the approach to allow access, without changing lanes, to:(a) Both an exit lane and the mainline at a freeway or expressway exit; or(b) Both diverging roadways at a freeway, expressway, or conventional road split.
155. Overhead Sign—a sign that is placed such that a portion or the entirety of the sign or its support
is directly above the roadway or shoulder such that vehicles travel below it. Typical installations
include signs placed on cantilever arms that extend over the roadway or shoulder, signs placedon sign support structures that span the entire width of the pavement, signs placed on mastarms or span wires either independently or that also support traffic control signals, and signs
placed on highway bridges that cross over the roadway.
156. Parking Area—a parking lot or parking garage that is separated from a roadway. Parallel,
perpendicular, or angle parking spaces along a roadway are not considered a parking area.
157. Parking Space—an area marked or designated for storage of a vehicle while the driver is
not present.
158. Preemption Clearance Interval—the part of a traffic signal sequence displayed as a result of apreemption request when vehicles are provided the opportunity to clear the railroad or light railtransit tracks, or a movable bridge, prior to the arrival of the train or boat for which the traffic
signal is being preempted.
159. Preemption Time Variability—the result that occurs when the traffic signal controller enters
the Preemption Clearance Interval with less than the maximum design Right-of-Way Transfer
Time or the speed of a train approaching the grade crossing varies.
160. Passive Grade Crossing—a grade crossing where none of the automatic traffic control devices
associated with an Active Grade Crossing Warning System are present and at which the traffic
control devices consist entirely of signs and/or markings.
161. Pathway—a general term denoting a public way for purposes of travel by authorized users
outside the traveled way and physically separated from the roadway by an open space or barrier
and either within the highway right-of-way or within an independent alignment. Pathways
include shared-use paths, but do not include sidewalks.
162. Pathway Grade Crossing—the general area where a pathway and railroad and/or light railtransit tracks cross at the same level, within which are included the tracks, pathway, and traffic
control devices for pathway traffic traversing that area.
163. Paved—having a roadway surface that has both a structural (weight bearing) and a sealing
purpose for the roadway, such as a bituminous surface treatment, mixed bituminous concrete,or Portland cement concrete.
164. Pedestrian—a person on foot, in a wheelchair, on other devices determined by local law to beequivalent, which might include skates or a skateboard.
165. Pedestrian Change Interval—an interval during which the flashing UPRAISED HAND
(symbolizing DONT WALK) signal indication is displayed.
166. Pedestrian Clearance Time—the time provided for a pedestrian crossing in a crosswalk, after
leaving the curb or edge of pavement, to travel to the far side of the traveled way or to a median.
167. Pedestrian Facility—a general term denoting a location where improvements and provisions
have been made to accommodate or encourage pedestrian activity.
168. Pedestrian Hybrid Beacon—see Hybrid Beacon.
169. Pedestrian Signal Head—a signal head, which contains the symbols WALKING PERSON(symbolizing WALK) and UPRAISED HAND (symbolizing DONT WALK), that is installed todirect pedestrians at a traffic control signal.
170. Permissive Mode—a mode of traffic control signal operation in which left or right turns are
permitted to be made after yielding to pedestrians, if any, and/or opposing traffic, if any. Whena CIRCULAR GREEN signal indication is displayed, both left and right turns are permitted
unless otherwise prohibited by another traffic control device. When a flashing YELLOWARROW or flashing RED ARROW signal indication is displayed, the turn indicated by thearrow is permitted.
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171. Physical Gore—a longitudinal point where a physical barrier or the lack of a paved surface
inhibits road users from crossing from a ramp or channelized turn lane or channelized entering
lane to the adjacent through lane(s) or vice versa.
172. Pictograph—a pictorial representation used to identify a governmental jurisdiction, an area ofjurisdiction, a governmental or other public transportation agency or provider, a military baseor branch of service, a governmental-approved university or college, a governmental-approved
institution, or a toll payment system.
173. Plaque—a traffic control device intended to communicate specific information to road users
through a word, symbol, or arrow legend that is placed immediately adjacent to a sign tosupplement the message on the sign. The difference between a plaque and a sign is that a plaquecannot be used alone. The designation for a plaque includes a “P” suffix.
174. Platoon—a group of vehicles or pedestrians traveling together as a group, either voluntarily or
involuntarily, because of traffic signal controls, geometrics, or other factors.
175. Portable Traffic Control Signal—see Highway Traffic Signal.
176. Post-Exit Ramp Lane Reduction—see Lane Reduction.
177. Post-Mounted Sign—a sign that is placed to the side of the roadway such that no portion of thesign or its support is directly above the roadway or shoulder.
178. Posted Speed Limit—a speed limit determined by law or regulation and displayed on Speed
Limit signs.
179. Preemption—the transfer of normal operation of a traffic control signal or a hybrid beacon toa special control mode of operation.
180. Preferential Lane—a highway lane or set of lanes, or a highway facility, reserved for the
exclusive use of one or more specific types of vehicles or of vehicles with a specific minimum
number of occupants.
181. Pre-Signal—see Highway Traffic Signal.
182. Pretimed Operation—a type of traffic control signal operation in which none of the signal
phases function on the basis of actuation.
183. Primary Signal Face—one of the required or recommended minimum number of signal faces
for a given approach or separate turning movement, but not including near-side signal faces
required as a result of the far-side signal faces exceeding the maximum distance from thestop line.
184. Principal Legend—place names, street names, and route numbers displayed on guide signs.
185. Priority Control—a means by which the assignment of right-of-way is obtained or modified.
186. Private Road—see Site Roadways Open to Public Travel.
187. Professional Engineer (P.E.)—An individual who has fulfilled education and experience
requirements and passed examinations that, under State licensure laws, permit the individual
to offer engineering services within areas of expertise directly to the public.
188. Protected Mode—a mode of traffic control signal operation in which left or right turns are
permitted to be made only when a left or right GREEN ARROW signal indication is displayed.
189. Public Road—any road, street, or similar facility under the jurisdiction of and maintained by apublic agency and open to public travel.
190. Push Button—a button to activate a device or signal timing for pedestrians, bicyclists, or otherroad users.
191. Push Button Information Message—a recorded message that can be actuated by pressing apush button when the walk interval is not timing and that provides the name of the street thatthe crosswalk associated with that particular push button crosses and can also provide otherinformation about the intersection signalization or geometry.
192. Push Button Locator Tone—a repeating sound that informs approaching pedestrians thata push button exists to actuate pedestrian timing or receive additional information and thatenables pedestrians with vision disabilities to locate the push button.
193. Queue Clearance Time—when used in Part 8, the time required for the design vehicle ofmaximum length stopped just inside the minimum track clearance distance to start up andmove through and clear the entire minimum track clearance distance.
194. Queue Cutter Signal—see Highway Traffic Signal.
195. Quiet Zone—a segment of a rail line, within which is situated one or a number of consecutive
public highway-rail grade crossings at which locomotive horns are not routinely sounded per
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196. Rail Traffic—every device in, upon, or by which any person or property can be transported
on rails or tracks and to which all other traffic must yield the right-of-way by law at grade
crossings, including trains, one or more locomotives coupled (with or without cars), otherrailroad equipment, and light rail transit operating in exclusive or semi-exclusive alignments.
Light rail transit operating in a mixed-use alignment, to which other traffic is not required toyield the right-of-way by law, is a vehicle and is not considered to be rail traffic.
197. Raised Pavement Marker—a device mounted on or in a road surface that has a height generally notexceeding approximately 1 inch above the road surface for a permanent marker, or not exceeding
approximately 2 inches above the road surface for a temporary flexible marker, and that is intended
to be used as a positioning guide and/or to supplement or substitute for pavement markings. Raised
pavement markers might also be recessed into or flush with the pavement surface.
198. Ramp Control Signal—see Highway Traffic Signal.
199. Red Clearance Interval—an interval that follows a yellow change interval and precedes the next
conflicting green interval.
200. Regulatory Sign—a sign that gives notice to road users of traffic laws or regulations.
201. Retroreflectivity—a property of a surface that allows a large portion of the light coming from apoint source to be returned directly back to a point near its origin.
202. Road—see Roadway.
203. Road User—a vehicle operator, bicyclist, or pedestrian, including persons with disabilities,
within the highway or on a site roadway open to public travel.
204. Roadway—that portion of a highway improved, designed, or ordinarily used for vehicular traveland parking lanes, but exclusive of the sidewalk, berm, or shoulder even though such sidewalk,berm, or shoulder is used by persons riding bicycles or other human-powered vehicles. In theevent a highway includes two or more separate roadways, the term roadway as used in thisManual shall refer to any such roadway separately, but not to all such roadways collectively.
205. Roadway Network—a geographical arrangement of intersecting roadways.
206. Roundabout—a circular intersection with yield control at entry, which permits a vehicle on
the circulatory roadway to proceed, and with deflection of the approaching vehicle counterclockwise around a central island.
207. Rumble Strip—a series of intermittent, narrow, transverse areas of rough-textured, slightly raised,or depressed road surface that extend across the travel lane to alert vehicle operators to unusual
traffic conditions or are located along the shoulder, along the roadway center line, or within
islands formed by pavement markings to alert road users that they are leaving the travel lanes.
208. Rural Highway—a type of roadway normally characterized by lower volumes, higher speeds,
fewer turning conflicts, and less conflict with pedestrians.
209. Scanning Graphic—a graphic designed for scanning by machine, and includes bar codes, quickresponse (QR) codes or other matrix bar code formats, or similar graphics.
210. School—a public or private educational institution recognized by the state education authority
for one or more grades K through 12 or as otherwise defined by the State.
211. School Zone—a designated roadway segment approaching, adjacent to, and beyond schoolbuildings or grounds, or along which school related activities occur.
212. Semi-Actuated—a type of traffic control signal operation in which at least one, but not all, signal
phases function on the basis of actuation.
213. Semi-Exclusive Alignment—a light rail transit track(s) or a bus rapid transit busway that is ina separate right-of-way or that is along a street or railroad right-of-way where motor vehicles,
bicycles, and pedestrians have limited access and cross only at designated locations, such as at
grade crossings where road users must yield the right-of-way to the light rail transit or the bus
rapid transit traffic.
214. Separate Turn Signal Face—a signal face that exclusively controls a turn movement and that
displays signal indications that are applicable only to the turn movement.
215. Separation Time—the component of maximum highway traffic signal preemption time during
which the minimum track clearance distance is clear of vehicular traffic prior to the arrival ofrail traffic.
216. Serviceable—a condition in which a traffic control device appears (day and night) and operates
as intended, beyond which it requires replacement due to damage or wear. Whether a device
is serviceable will depend on the type of device under consideration. In general, if the device
is capable of being serviced with minimal effort or replacement parts so that it continues toappear and operate as intended, and the device is otherwise substantially intact, then it can beconsidered to be in serviceable condition. If the device is damaged or not operational beyond
reasonable repair, then it is likely no longer serviceable.
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Page 25217. Shared Roadway—a roadway that is officially designated and marked as a bicycle route, butwhich is open to motor vehicle travel and upon which no bicycle lane is designated.
218. Shared Turn Signal Face—a signal face, for controlling both a turn movement and the adjacentthrough movement, that always displays the same color of circular signal indication that theadjacent through signal face or faces display.
219. Shared-Use Path—a bikeway outside the traveled way and physically separated from motorized
vehicular traffic by an open space or barrier and either within the highway right-of-way orwithin an independent alignment. Shared-use paths are also used by pedestrians (including
skaters, users of manual and motorized wheelchairs, and joggers) and other authorized
motorized and non-motorized users.
220. Shoulder—a longitudinal area contiguous with the traveled way that is used for accommodationof stopped vehicles for emergency use and for lateral support of base and surface courses, andthat is graded for emergency stopping. A shoulder might be paved or unpaved. A paved shoulder
might be opened to part-time travel by some or all vehicles and might also be available for use
by pedestrians and/or bicycles in the absence of other pedestrian or bicycle facilities.
221. Sidewalk—that portion of a street between the curb line, or the lateral line of a roadway, andthe adjacent property line or on easements of private property that is paved or improved andintended for use by pedestrians.
222. Sidewalk Extension—a pedestrian facility at an intersection or midblock crosswalk which
extends the sidewalk by physically and visually narrowing the roadway.
223. Sidewalk Grade Crossing—the portion of a highway-rail grade crossing or of a highway-lightrail transit grade crossing where a sidewalk and railroad tracks or a sidewalk and light railtransit tracks cross at the same level, within which are included the tracks, sidewalk, and traffic
control devices for sidewalk users traversing that area.
224. Sign—with regard to controlling traffic, any traffic control device that is intended tocommunicate specific information to road users through a word, symbol, and/or arrow legend.
Signs do not include highway traffic signals, pavement markings, delineators, or channelization
devices. Signs whose purpose is unrelated to traffic control are addressed in Section 1A.02.
225. Sign Assembly—a group of signs, located on the same support(s), that supplement one another inconveying information to road users.
226. Sign Illumination—either internal or external lighting that shows similar color by day or night.
Street or highway lighting shall not be considered as meeting this definition.
227. Sign Legend—all word messages, logos, pictographs, and symbol and arrow designs that are
intended to convey specific meanings. The border, if any, on a sign is not considered to be a partof the legend.
228. Sign Panel—a separate panel or piece of material containing a word, logo, pictograph, symbol,
and/or arrow legend that is affixed to the face of a sign.
229. Signal—See Highway Traffic Signal.
230. Signal Backplate—a thin strip of material that extends outward from and parallel to a signal face on
all sides of a signal housing to provide a background for improved visibility of the signal indications.
231. Signal Coordination—the establishment of timed relationships between adjacent traffic
control signals.
232. Signal Dimming—a reduction of the light output from a signal indication, hybrid beacon, or
rectangular rapid-flashing beacon indication, typically for nighttime conditions, to a value thatis below the minimum specified intensity for daytime conditions. If a variety of intensity levels
are used during daytime conditions and all of the various levels (including the lowest of theintensities) are above the minimum specified intensity for daytime conditions, this would not be
considered to be signal dimming.
233. Signal Face—an assembly of one or more signal sections that is provided for controlling one ormore traffic movements on a single approach.
234. Signal Head—an assembly of one or more signal faces that is provided for controlling traffic
movements on one or more approaches.
235. Signal Housing—that part of a signal section that protects the light source and other requiredcomponents.
236. Signal Indication—the illumination of a signal lens or equivalent device.
237. Signal Lens—that part of the signal section that redirects the light coming directly from thelight source and its reflector, if any.
238. Signal Louver—a device that can be mounted inside a signal visor to restrict visibility of a signal
indication from the side or to limit the visibility of the signal indication to a certain lane orlanes, or to a certain distance from the stop line.
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239. Signal Phase—the right-of-way, yellow change, and red clearance intervals in a cycle that areassigned to an independent traffic movement or combination of movements.
240. Signal Section—the assembly of a signal housing, signal lens, if any, and light source withnecessary components to be used for displaying one signal indication.
241. Signal Sequence (Sequence of Indications)—the order of appearance of signal indications during
successive intervals of a signal cycle.
242. Signal System—two or more traffic control signals operating in signal coordination.
243. Signal Timing—the amount of time allocated for the display of a signal indication.
244. Signal Visor—that part of a signal section that directs the signal indication specifically toapproaching traffic and reduces the effect of direct external light entering the signal lens.
245. Signing—individual signs or a group of signs, not necessarily on the same support(s), that
supplement one another in conveying information to road users.
246. Simultaneous Preemption—notification of approaching rail traffic is forwarded to the highway
traffic signal controller unit or assembly and railroad or light rail transit active warning devices
at the same time.
247. Site Roadways Open to Public Travel—Roadways and bikeways on sites of shopping centers,
office parks, airports, schools, universities, sports arenas, recreational parks, and other similarbusiness, governmental, and/or recreation facilities that are publicly or privately owned but
where the public is allowed to travel without full-time access restrictions. Two types of roadways
are not included in this definition: (1) roadways where access is restricted at all times by gates
and/or guards to residents, employees, or other specifically-authorized persons; and (2) private
highway-rail grade crossings. Site roadways open to public travel do not include parking areas(see definition in this Section), including the driving aisles (see definition in this Section) withinthose parking areas.
248. Special-Purpose Road—a low-volume, low-speed road that serves recreational areas or resource
development activities.
249. Speed—speed is defined based on the following classifications:(a) Average Speed—the summation of the instantaneous or spot-measured speeds at a specificlocation of vehicles divided by the number of vehicles observed.
(b) Design Speed—a selected speed used to determine the various geometric design features ofa roadway.
(c) 85th-Percentile Speed—the speed at or below which 85 percent of the motor vehicles travel.
(d) Operating Speed—a speed at which a typical vehicle or the overall traffic operates.
Operating speed might be defined with speed values such as the average, pace, or 85thpercentile speeds.
(e) Pace—the 10 mph speed range representing the speeds of the largest percentage of vehicles
in the traffic stream.
250. Speed Limit—the maximum (or minimum) speed applicable to a section of highway asestablished by law or regulation.
251. Speed Zone—a section of highway with a speed limit that is established by law or regulation, butwhich might be different from a legislatively-specified statutory speed limit.
252. Splitter Island—a median island used to separate opposing directions of traffic entering andexiting a roundabout.
253. Station Crossing—a pathway grade crossing that is associated with a station platform.
254. Statutory Speed Limit—a speed limit established by legislative action (such as Federal orState law) that typically is applicable for a particular class of highways with specified design,functional, jurisdictional, and/or location characteristics and that is not necessarily displayedon Speed Limit signs.
255. Steady (Steady Mode)—the continuous display of a signal indication for the duration of aninterval, signal phase, or consecutive signal phases.
256. Stop Line—a solid white pavement marking line extending across approach lanes to indicate thepoint at which a stop is intended or required to be made.
257. Street—see Highway.
258. Supplemental Signal Face—a signal face that is not a primary signal face but which is provided
for a given approach or separate turning movement to enhance visibility or conspicuity.
259. Swing Gate—a self-closing fence-type gate designated to swing open away from the track area
and return to the closed position upon release.
260. Symbol—the approved design of a pictorial or graphical representation of a specific traffic
control message for signs, pavement markings, traffic control signals, or other traffic control
devices, as shown in the MUTCD.
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Page 27261. Temporary Traffic Control Signal—see Highway Traffic Signal.
262. Temporary Traffic Control Zone—an area of a highway, pedestrian or bicycle facility where roaduser conditions are changed because of a work zone or incident by the use of temporary traffic
control devices, flaggers, uniformed law enforcement officers, or other authorized personnel.
263. Theoretical Gore—a longitudinal point at the upstream end of a neutral area at an exit ramp
or channelized turn lane where the channelizing lines that separate the ramp or channelized
turn lane from the adjacent through lane(s) begin to diverge, or a longitudinal point at thedownstream end of a neutral area at an entrance ramp or channelized entering lane where
the channelizing lines that separate the ramp or channelized entering lane from the adjacentthrough lane(s) intersect each other.
264. Through Train—a train movement that continues without stopping or reversing direction
throughout the entire length of the rail traffic detection circuit length approaching a highwayrail grade crossing.
265. Timed Exit Gate Operating Mode—a mode of operation where the exit gate descent at a grade
crossing is based on a predetermined time interval.
266. Toll Booth—a shelter where a toll attendant is stationed to collect tolls or issue toll tickets. A toll
booth is located adjacent to a toll lane and is typically set on a toll island.
267. Toll Collection—manual or electronic methods and elements used to collect a fee for use of a toll
facility. Toll collection methods include:(a) Electronic Toll Collection (ETC)—a cashless system for automated collection of tolls
from moving or stopped vehicles through wireless technologies such as radio-frequency
communication or optical scanning. ETC systems are classified as one of the following:(1) Systems that require users to have registered toll accounts, with the use of equipment
inside or on the exterior of vehicles, such as a transponder or barcode decal, that
communicates with or is detected by roadside or overhead receiving equipment, orwith the use of license plate optical scanning, to automatically deduct the toll from theregistered user account,(2) Systems that do not require users to have registered toll accounts because vehicle license
plates are optically scanned and invoices for the toll amount are typically sent throughpostal mail to the address of the vehicle owner, or(3) Systems that allow electronic toll collection for both registered and non-registered
toll accounts.
(b) Open-Road Tolling (ORT)—a system designed to allow electronic toll collection (ETC) fromvehicles traveling at posted speeds. Open-road tolling might be used on toll roads or toll
facilities in conjunction with toll plazas. Open-road tolling is also typically used on managed
lanes and on toll facilities that only accept payment by ETC.
(c) Manual Toll Collection—a system of toll collection from stopped vehicles throughacceptance of cash, toll tickets, tokens, or credit cards, and may involve issuance of receipts.
Toll collection may be by a machine or toll booth attendant.
(1) Toll-Ticket System—a toll system in which the user of a toll road must stop to receive aticket from a machine or toll booth attendant upon entering the toll facility. The ticket
denotes the user’s point of entry and, upon exiting the toll system, the user surrenders
the ticket and is charged a toll based on the distance traveled between the points ofentry and exit.
(2) Attended Lane (Manual Lane)—a toll lane adjacent to a toll booth occupied by ahuman toll collector who makes change, issues receipts, and performs other toll-related
functions. Attended lanes at toll plazas typically require vehicles to stop to pay the toll.
(3) Exact Change Lane (Automatic Lane)—a non-attended toll lane that has a receptacle
into which road users deposit coins totaling the exact amount of the toll. Exact Change
lanes at toll plazas typically require vehicles to stop to pay the toll.
268. Toll Island—a raised island on which a toll booth or other toll collection and related equipment
are located.
269. Toll Lane—an individual lane located within a toll plaza in which a toll payment is collected or,for toll-ticket systems, a toll ticket is issued.
270. Toll Plaza—the location at which tolls are collected consisting of a grouping of toll booths, tollislands, toll lanes, and, typically, a canopy. Toll plazas might be located on highway mainlines
or on interchange ramps. A mainline toll plaza is sometimes referred to as a barrier toll plaza
because it interrupts the traffic flow.
271. Toll Road (Facility)—a road or facility that is open to traffic only by payment of a user toll or fee.
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MUTCD 11th Edition

272. Traffic—pedestrians, bicyclists, ridden or herded animals, vehicles, streetcars, and otherconveyances either singularly or together while using for purposes of travel any highway or site
roadway open to public travel.
273. Traffic Control Device—all signs, signals, markings, channelization devices, or other devices
that use colors, shapes, symbols, words, sounds, and/or tactile information for the primary
purpose of communicating a regulatory, warning, or guidance message to road users on a street,highway, pedestrian facility, bikeway, pathway, or site roadway open to public travel. Section
1A.02 contains information regarding items that are not traffic control devices.
274. Traffic Control Signal (Traffic Signal)—see Highway Traffic Signal.
275. Train—one or more locomotives coupled, with or without cars, that operates on rails or tracks
and to which all other traffic must yield the right-of-way by law at highway-rail grade crossings.
276. Transverse Markings—pavement markings that are generally placed perpendicular and acrossthe flow of traffic such as shoulder markings; word, symbol, and arrow markings; stop lines;
crosswalk lines; parking space markings; and others.
277. Traveled Way—the portion of the roadway for the movement of vehicles, exclusive of theshoulders, berms, sidewalks, and parking lanes.
278. Turn Bay—a lane for the exclusive use of turning vehicles that is formed on the approach to thelocation where the turn is to be made. In most cases where turn bays are provided, drivers who
desire to turn must move out of a through lane into the newly-formed turn bay in order to turn.
A through lane that becomes a turn lane is considered to be a lane drop rather than a turn bay.
279. Two-Stage Bicycle Turn Box—a designated area at an intersection intended to provide bicyclists
a place to wait for traffic to clear before proceeding in a different direction of travel.
280. Uncontrolled Approach—an approach on which vehicles are not controlled by a traffic control
signal, hybrid beacon, STOP sign, or YIELD sign.
281. Upstream—a term that refers to a location that is encountered by traffic prior to a downstream
location as it flows in an “upstream to downstream” direction. For example, “the upstream endof a lane line separating the turn lane from a through lane on the approach to an intersection”
is the end of the line that is furthest from the intersection.
282. Urban Street—a type of street normally characterized by relatively low speeds, wide ranges oftraffic volumes, narrower lanes, frequent intersections and driveways, significant pedestrian
traffic, and more businesses and houses.
283. Variable Message Sign—see Changeable Message Sign.
284. Vehicle—every device in, upon, or by which any person or property can be transported or
drawn upon a highway, except trains and light rail transit operating in exclusive or semiexclusive alignments. Light rail transit equipment operating in a mixed-use alignment, to which
other traffic is not required to yield the right-of-way by law, is a vehicle.
285. Vibrotactile Pedestrian Device—an accessible pedestrian signal feature that communicates, by
touch, information about pedestrian timing using a vibrating surface.
286. Visibility-Limited Signal Face or Visibility-Limited Signal Section—a type of signal face orsignal section designed (or shielded, hooded, or louvered) to restrict the visibility of a signal
indication from the side, to a certain lane or lanes, or to a certain distance from the stop line.
287. Walk Interval—an interval during which the WALKING PERSON (symbolizing WALK) signal
indication is displayed.
288. Warning Light—a portable, powered, yellow, lens-directed, enclosed light that is used in a
temporary traffic control zone in either a steady burn or a flashing mode.
289. Warning Sign—a sign that gives notice to road users of a situation that might not bereadily apparent.
290. Warrant—a warrant describes a threshold condition based upon average or normal conditions
that, if found to be satisfied as part of an engineering study, shall result in analysis of othertraffic conditions or factors to determine whether a traffic control device or other improvement
is justified. Warrants are not a substitute for engineering judgment. The fact that a warrant
for a particular traffic control device is met is not conclusive justification for the installation of
the device.
291. Wayside Horn System—a stationary horn (or a series of horns) located at a grade crossing thatis used in conjunction with train-activated or light rail transit-activated warning systems toprovide audible warning of approaching rail traffic to road users on the highway or pathway
approaches to a grade crossing, either as a supplement or alternative to the sounding of alocomotive horn.
292. Worker—a person on foot whose duties place him or her within the right-of-way of a street,highway, or pathway, such as: construction and maintenance forces; survey crews; utility crews;
Sect. 1C.02

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responders to incidents within the right-of-way; and law enforcement personnel when directing
traffic, investigating crashes, and handling lane closures, obstructed roadways, and disasters
within the right-of-way.
293. Wrong-Way Arrow—a slender, elongated, white pavement marking arrow placed upstream
from the ramp terminus to indicate the correct direction of traffic flow. Wrong-way arrows areintended primarily to warn wrong-way road users that they are going in the wrong direction.
294. Yellow Change Interval—the first interval following the green or flashing arrow interval during
which the steady yellow signal indication is displayed.
295. Yield Line—a row of solid white isosceles triangles pointing toward approaching vehicles
extending across approach lanes to indicate the point at which the yield is intended or required
to be made.

Section 1C.03 Meanings of Acronyms and Abbreviations Used in this Manual
01

Standard:
The following acronyms and abbreviations, when used in this Manual, shall have thefollowing meanings:
1. AADT—annual average daily traffic
2. AASHTO—American Association of State Highway and Transportation Officials
3. AC—alternating current
4. ADA—Americans with Disabilities Act
5. ADAS—Advanced Driver Assistance Systems
6. ADS—Automated Driving System
7.
ADT—average daily traffic
8. AFAD—Automated Flagger Assistance Device
9.
ANSI—American National Standards Institute
10. AREMA—American Railway Engineering and Maintenance-of-Way Association
11. AV—automated vehicle
12. cd/lx/m2—candelas per lux per square meter
13. CFR—Code of Federal Regulations
14. CMS—changeable message sign
15. dBA—A-weighted decibels
16. DC—direct current
17. DDT—Dynamic Driving Task
18. EPA—Environmental Protection Agency
19. ETC—electronic toll collection
20. EV—electric vehicle
21. FHWA—Federal Highway Administration
22. FRA—Federal Railroad Administration
23. ft—foot or feet
24. FTA—Federal Transit Administration
25. HOV—high-occupancy vehicle
26. IEEE—Institute of Electrical and Electronics Engineers
27. IES—Illuminating Engineering Society
28. ILEV—inherently low emission vehicle
29. in—inch(es)30. ISEA—International Safety Equipment Association
31. ITE—Institute of Transportation Engineers
32. ITS—intelligent transportation systems
33. L—taper length
34. LED—light-emitting diode35. LP—liquified petroleum
36. LRT—light rail transit
37. mi—mile(s)38. MPH or mph—miles per hour
39. MUTCD—Manual on Uniform Traffic Control Devices for Streets and Highways
40. N—length of one line segment plus one gap of a broken line
41. NCEES—National Council of Examiners for Engineering and Surveying
42. NCHRP—National Cooperative Highway Research Program
43. ODD—Operational Design Domain
44. OPM—U.S. Office of Personnel Management

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45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.

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MUTCD 11th Edition

ORT—open-road tolling
PCMS—portable changeable message sign
PRT—perception-response time
RRFB—rectangular rapid-flashing beacon
RV—recreational vehicle
SAE—Society of Automotive Engineers
SHV—Specialized Hauling Vehicle
SPF—safety performance function
TA—Typical Application
TDD—telecommunication device for the deaf
TRB—Transportation Research Board
TTC—temporary traffic control
U.S.—United States
U.S.C.—United States CodeUSDOT—United States Department of Transportation
UVC—Uniform Vehicle CodeVPH or vph—vehicles per hour
V2I—vehicle-to-infrastructure

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CHAPTER 1D. PROVISIONS APPLICABLE TO TRAFFIC CONTROL DEVICES IN GENERAL
Section 1D.01 Purpose and Principles of Traffic Control Devices

Support:01
The purpose of traffic control devices, as well as the principles for their use, is to promote highway safety,
inclusion and mobility of all road users, and efficiency by providing for the orderly movement of road users onstreets, highways, bikeways, and site roadways open to public travel throughout the Nation. Section 1A.03 contains
additional information on target road users.
02
This Manual contains the basic principles that govern the design and use of traffic control devices for all
streets, highways, bikeways, and site roadways open to public travel (see definition in Section 1C.02) regardlessof type or class or the public agency, official, or owner having jurisdiction. The text of this Manual specifies the
restriction on the use of a device if it is intended for limited application or for a specific system. It is important thatthese principles be given primary consideration in the selection and application of each device.
Guidance:
03
To be effective, a traffic control device should:
A. Fulfill a need;
B. Command attention;
C. Convey a clear, simple meaning;
D. Command respect from road users; andE. Give adequate time for proper response.
04
Design, placement, operation, maintenance, and uniformity are aspects that should be carefully considered
in order to maximize the ability of a traffic control device to be consistent with the five principles listed in
Paragraph 3 of this Section. Vehicle speed and road-user types should be carefully considered as an element thatgoverns the design, operation, placement, and location of various traffic control devices.
05
The proper use of traffic control devices should provide the road user with the information necessary tosafely, efficiently, and lawfully use the streets, highways, pedestrian facilities, and bikeways.
Standard:
06
Traffic control devices used on site roadways open to public travel shall have the same shape, color,and meaning as those required by the MUTCD for use on public highways, except as provided otherwise
elsewhere in this Manual. Sign size exceptions are noted in each Part as applicable.

Section 1D.02 Responsibility and Authority for Traffic Control Devices

Standard:
01
The responsibility for the design, placement, operation, maintenance, and uniformity of traffic control
devices in compliance with the provisions of this Manual shall rest with the public agency or the official
having jurisdiction, or, in the case of site roadways open to public travel, with the private owner or private
official having jurisdiction.
02
All regulatory traffic control devices shall be supported by laws, ordinances, or regulations.
03
Traffic control devices, public announcements or notices, and other signs or messages within the
highway right-of-way shall be placed only as authorized by a public authority or the official having
jurisdiction, or, in the case of site roadways or private toll roads open to public travel, by the private owneror private official having jurisdiction, for the purpose of regulating, warning, or guiding traffic.
04
When the public agency or the official having jurisdiction over a street or highway or, in the case of site
roadways open to public travel, the private owner or private official having jurisdiction, has granted proper
authority, others such as contractors and public utility companies shall be allowed to install temporary
traffic control devices in temporary traffic control zones. Such traffic control devices shall comply with theprovisions of this Manual.
05
Signs and other devices that do not have any traffic control purpose that are placed within the highway
right-of-way shall not be located where they will interfere with, or detract from, traffic control devices.
Support:06
States are encouraged to adopt, through policy or legislation, the provisions of 23 CFR 750.108 that restrict
outdoor advertising from resembling traffic control devices.

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Section 1D.03 Engineering Study and Engineering Judgment

Support:01
Definitions of professional engineer, engineering study, and engineering judgment are provided in Section 1C.02.
02
The application of engineering study and engineering judgment is a fundamental principle of the use of traffic
control devices. It is for this reason that, in most cases, the selection of a particular device is not required by aStandard provision, but is determined by engineering study or engineering judgment. Many Standard provisions inthis Manual specifically require, by explicit language in the individual provisions or by implication, the applicationof engineering study or engineering judgment in applying those Standards. Site-specific conditions might resultin the determination that it is impossible or impracticable to comply with a Standard at that location. In such acase, a deviation from the requirement of a particular Standard at that location might be the only possibility. Insuch limited, specific cases, the deviation is allowed, provided that the agency or official having jurisdiction fully
documents, through an engineering study, the engineering basis for the deviation.
Standard:
03
This Manual describes the application of traffic control devices, but shall not be a legal requirement for
their installation.
Support:
04
The MUTCD does not mandate, and is not intending to imply, that an engineer must make the final decision
whether to implement or execute the determination or advice of an engineer by installing or constructing the traffic
control device to the engineer’s specification in the field. Rather, the engineer, individual under supervision of anengineer, or other individual as duly authorized by State law to engage in the practice of engineering, develops anengineering-based solution that includes the specifications for selection and placement of traffic control devices,
but the responsibility for a final decision to implement that solution rests with the agency having jurisdiction over
the roadway, after consultation with and based on advice from the engineer.
Guidance:
05
The decision to use a particular device at a particular location should be made on the basis of either
an engineering study or the application of engineering judgment by an engineer, someone under the directsupervision of an engineer, or other individual as duly authorized by State law to engage in the practice ofengineering. Thus, while this Manual provides Standards, Guidance, and Options for design and application of
traffic control devices, this Manual should not be considered a substitute for engineering judgment. Engineering
judgment should be exercised in the selection and application of traffic control devices, as well as in the locationand design of roads and streets that the devices complement.
06
Early in the processes of location and design of roads and streets, engineers should coordinate such locationand design with the design and placement of the traffic control devices to be used with such roads and streets.
07
Jurisdictions, or owners of site roadways or private toll roads open to public travel, with responsibility for
traffic control that do not have an engineer on their staff who is trained and/or experienced in traffic control
devices should seek engineering assistance from others, such as the State transportation agency, their county,
a nearby large city, or a traffic engineering consultant.
Support:08
The provisions of this Manual are intended to be interpreted and applied by engineers or those under thesupervision of an engineer. The construction of the provisions of this Manual, therefore, are informed by bases
referenced in Paragraphs 9 and 10 of this Section.
09
The National Council of Examiners for Engineering and Surveying (NCEES) has defined the practice ofengineering as “any service or creative work requiring engineering education, training, and experience in theapplication of engineering principles and the interpretation of engineering data to engineering activities that
potentially impact the health, safety, and welfare of the public.” The practice of engineering is, therefore, subject
to regulation in the public interest and is regulated by the State licensing boards in order to safeguard the health,safety, and welfare of the public. The NCEES has defined an engineer as “an individual who is qualified topractice engineering by reason of engineering education, training, and experience in the application of engineering
principles and the interpretation of engineering data.”
10
The U.S. Office of Personnel Management (OPM) has defined the professional knowledge of engineering
as “the comprehensive, in-depth knowledge of mathematical, physical, and engineering sciences applicable to a
specialty field of engineering that characterizes a full 4-year engineering program leading to a bachelor’s degree,or the equivalent.” The OPM has defined professional ability to apply engineering knowledge as “the ability
to (a) apply fundamental and diversified professional engineering concepts, theories, and practices to achieveengineering objectives with versatility, judgment, and perception; (b) adapt and apply methods and techniquesof related scientific disciplines; and (c) organize, analyze, interpret, and evaluate scientific data in the solution ofengineering problems.”
11
Requisite technical training in the application of the principles of the MUTCD might be available from theState’s Local Technical Assistance Program (LTAP) for needed engineering guidance and assistance.
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Section 1D.04 Design of Traffic Control Devices

Guidance:
Devices should be designed so that features such as size, shape, color, composition, lighting or retroreflection,and contrast are combined to draw attention to the devices; so that size, shape, color, and simplicity of message
combine to produce a clear meaning; so that legibility and size combine with placement to provide adequate
time for response; and so that uniformity, size, legibility, and reasonableness of the message combine tocommand respect.
Option:02
Except for symbols and colors, minor modifications in the specific design elements of a device may be madebased on an engineering study or engineering judgment, in accordance with Paragraph 3 of this Section, provided
the essential appearance characteristics are preserved.
Guidance:03
Aspects of the standard design of a traffic control device should not be modified unless there is ademonstrated need in unusual circumstances, based on an engineering study or engineering judgment.
Support:04
An example of acceptably modifying the design of a device would be to modify the Combination Horizontal
Alignment/Intersection (W1-10) sign to show intersecting side roads on both sides rather than on just one side of
the major road within the curve.
01

Section 1D.05 Color CodeSupport:The following color code establishes general meanings for 11 colors of a total of 13 colors that have been
identified as being appropriate for use in conveying traffic control information.
Standard:
02
The general meaning of the 13 colors shall be as follows:
A. Black—regulation
B. Blue—road-user services guidance, tourist information, and evacuation route
C. Brown—recreational and cultural interest area guidance
D. Coral—reserved for future designation (see Paragraph 4 of this Section)
E. Fluorescent Pink—incident management
F. Fluorescent Yellow-Green—pedestrian warning, bicycle warning, playground warning, school bus
warning, and school warning
G. Green—indicated movements or actions permitted and direction guidance
H. Light Blue—reserved for future designation (see Paragraph 4 of this Section)
I. Orange—temporary traffic control
J. Purple—restricted to use only by vehicles with registered electronic toll collection (ETC) accounts
K. Red—stop or prohibition
L. White—regulation
M. Yellow—warning
03
These colors shall be used only as prescribed for the specific devices or applications throughout
this Manual.
Support:04
The two colors for which general meanings have not yet been assigned are being reserved for futureapplications that will be determined only by the FHWA after consultation with the States, the engineeringcommunity, and the general public. The meanings described in this Section are of a general nature. More specificassignments of colors are given in the individual Parts of this Manual relating to each class of devices.
05
Tolerance limits for each color are contained in 23 CFR Part 655, Appendix to Subpart F and are available atthe Federal Highway Administration’s MUTCD Web site at http://mutcd.fhwa.dot.gov.
01

Section 1D.06 Public Domain, Copyrights, and Patents
01Standard:
Traffic control device design or application provisions contained in this Manual shall be in the publicdomain. Traffic control devices contained in this Manual shall not be protected by a patent, trademark,or copyright, except for the Interstate Shield, 511 Travel Information pictograph, National Scenic Byway
graphic, and any items under the stewardship of or owned by FHWA.

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MUTCD 11th Edition

A traffic control device design or application shall not be eligible for official experimentation(see Section 1B.05) or interim approval (see Section 1B.07) unless it is in the public domain. Express
abandonment of any and all forms of proprietary protection, such as patents, trademarks, or copyrights,
related to the design and application of the traffic control device shall satisfy the requirement for the traffic
control device to be in the public domain.
03
The requirement for the traffic control device to be in the public domain shall not apply to individualcomponents used in the assembly or manufacture of the traffic control device.
Support:04
The limitation on patented, trademarked, or copyrighted traffic control devices, applies to the message thatthe device conveys to the road user. If a patent or other protection covers the device’s communication to the roaduser by virtue of its appearance, audible message, or other aspects of the message conveyed (such as the order inwhich traffic control signal indications change from green to yellow and red), then the device is considered to beprotected and not in the public domain. Such a device is precluded from inclusion in this Manual. The purposeof this limitation is to ensure uniformity of the messaging of individually approved traffic control devices. This
limitation does not apply to other aspects of a device (such as internal controls, circuitry, electronics, mechanics,
or housing) so long as the appearance, audible message, or other aspects of the message conveyed, including themanner of conveyance, remain freely reproducible by all without infringing on any proprietary rights or interests.
This Manual does not prohibit such other aspects of a traffic control device that meet the legal requirements frombeing protected through patent, trademark, or copyright; and does not restrict components, parts, manufacturing
processes, or similar aspects of traffic control devices from being patented or otherwise protected. Examples of
acceptable protected traffic control device components or parts might include: sign sheeting or retroreflectivity
technology, internal electronic components of traffic signal controllers, and breakaway sign support mechanisms.
05
Pictographs, as defined in Section 1C.02, are embedded in traffic control devices, but the pictographs
themselves are not considered traffic control devices for the purposes of Paragraph 4 of this Section.
06
Business identification logos, as defined in Section 1C.02, are embedded in traffic control devices, but thelogos themselves are not considered traffic control devices for the purposes of Paragraph 4 of this Section.
02

Section 1D.07 AdvertisingStandard:
Traffic control devices or their supports shall not bear any advertising message or any other message
that is not related to traffic control.
Support:02
Acknowledgment signs (see Section 2H.13), Specific Service signs (see Chapter 2J), and Tourist-Oriented
Directional signs (see Chapter 2K) are not considered advertising.
01

Section 1D.08 Abbreviations Used on Traffic Control Devices

Standard:
01
When the word messages shown in Table 1D-1 need to be abbreviated in connection with traffic control
devices, the abbreviations shown in Table 1D-1 shall be used.
02
When the word messages shown in Table 1D-2 need to be abbreviated on a portable changeable
message sign, the abbreviations shown in Table 1D-2 shall be used. Unless indicated by an asterisk, theseabbreviations shall only be used on portable changeable message signs.
Guidance:
03
The abbreviations for the words listed in Table 1D-2 that also show a prompt word should not be used on aportable changeable message sign (or on a static sign if indicated in Table 1D-2 by an asterisk) unless the prompt
word shown in Table 1D-2 either precedes or follows the abbreviation, as applicable.
Standard:
04
The abbreviations shown in Table 1D-3 shall not be used in connection with traffic control devices
because of their potential to be misinterpreted by road users.
Guidance:05
If Table 1D-1 or 1D-2 indicates that more than one abbreviation is allowed for a given word or phrase, thesame abbreviation should be used throughout a single jurisdiction.
06
Except as otherwise provided in Table 1D-1 or 1D-2 or unless necessary to avoid confusion, periods,
commas, apostrophes, question marks, ampersands, and other punctuation marks or characters that are notletters or numerals should not be used in any abbreviation.

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Table 1D-1. Acceptable Abbreviations
General Abbreviations
Standard
Abbreviation

Word Message

Word Message

Standard
Abbreviation

Afternoon / Evening

PM

Mile(s)MI

Alternate

ALT

Miles per Hour

MPH

AM RadioAM

Minimum

MIN

AvenueAve, Av*

Minute(s)MIN, MINS

Bicycle(s)BIKE, BIKES

Morning / Late NightAM

Boulevard

Blvd*

Mount

Mt**

Bridge(See Table 1D-2)

Mountain

Mtn**

CB RadioCB

National

Natl**

Center

Ctr**

North

N

CircleCir*

Northeast

NE

Civil Defense

CD

Northwest

NW

Compressed Natural Gas

CNG

Parkway

Pkwy*

Court

Ct*

Pedestrian(s)PED, PEDS

Crossing (other than highway-rail)

X-ING

Place

Pl*

Drive

Dr*

Pounds

LBS

East

E

Road

Rd*

Electric Vehicle

EV

Saint

St**

Expressway

Expwy*

South

S

Feet

FT

SoutheastSE

FM RadioFM

Southwest

SW

Freeway

Fwy*(See Table 1D-2)

Hazardous Material(s)HAZMAT, HAZMATS

State, county, or other non-US or
non-Interstate numbered route

High Occupancy Vehicle(s)HOV

StreetSt*

Highway

Hwy*

Telephone

PHONE

Hospital

HOSP

Temporary

TEMP

Hour(s)HR, HRS

TerraceTer*

Information

INFO

Thruway

Thwy*

Inherently Low Emission Vehicle

ILEV

Ton(s)

T

International

Intl

Trail

Tr*

Interstate(See Table 1D-2)

Turnpike

Tpk*

Junction / IntersectionJCT

Two-Way Intersection, TwoWay Traffic

2-WAY

Lane

(See Table 1D-2)

US Numbered Route(See Table 1D-2)

Liquified Petroleum Gas

LP-GASWest

W

Maximum

MAX

Days of the Week
Day

Standard
Abbreviation

Day

Standard
Abbreviation

SundaySUN

Thursday

THURS***

MondayMON

FridayFRI

Tuesday

TUES***

SaturdaySAT

Wednesday

WED* Abbreviation shall not be used for any application other than the name of a roadway. See Table 2D-3 for complete listof street name descriptors. Examples include: Bayshore Fwy, Cross County Hwy, Mid-County Pkwy** Abbreviation shall not be used for any application other than as a descriptor or title within a proper name.
Examples include: Vestal Ctr, Mt Hope, Pocono Mtn, Eldorado Natl Forest, St Louis*** Tuesday and Thursday may be abbreviated on a Changeable Message Sign (CMS) to TUE and THU, respectively, when
the number of Characters in a message to be displayed cannot be practically reduced through rewording to fit the
number of characters supported by the CMS, such as might occur at times on a portable CMS.
Note: Abbreviations shown in upper- and lower-case lettering may be in all upper-case lettering when displayed on a changeable
message sign with lower resolution that will not accommodate lower-case letter forms. See Chapter 2L of this Manual.
December 2023

Sect. 1D.08

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MUTCD 11th Edition

Table 1D-2. Abbreviations that Shall be Used Only for
Temporary Messages on Portable Changeable Message Signs (Sheet 1 of 2)
Word Message

Standard
Abbreviation

Prompt Word
Preceding theAbbreviation

Prompt Word
Following theAbbreviation

ExampleACCS ROAD

Access

ACCS

—

Road

Ahead

AHD

Fog

—

FOG AHD

Blocked

BLKD

Lane

—

2 LANES BLKD

BridgeBR*[Name]—BAY BR

Cannot

CANT

—

—

—

Center

CNTR

—

Lane

CNTR LANE, CNTR LN

Chemical

CHEM

—

Spill

CHEM SPILL

Condition

COND

Traffic—

TRAFFIC COND

Congested

CONG

Traffic—

TRAFFIC CONG AHD

Construction

CONST

—

Ahead

CONST AHEAD

Crossing

XING

—

—

PED XING

Do Not

DONT

—

—

—

Downtown

DWNTN—

Traffic

DWNTN TRAFFIC

EAST

Route Number, Road Name—

I-4 EAST

E-BND—

Lane, Traffic

E-BND LANE

Emergency

EMER

—

—

EMER VEHICLES

Entrance, Enter

ENT

—

—

ENT TO I-90

Exit

EX

Next

—

NEXT EX

Express

EXP

—

Lane

EXP LANE OPEN

Frontage

FRNTG

—

Road

FRNTG RD

Hazardous

HAZ—

Driving

HAZ DRIVING

EastboundRR XING——RR XING

Interstate

Highway-Rail Grade Crossing

I-*—[Number]

I-80

It Is

ITS

—

—

—

LN, LNS

Right, Left, Center—

LEFT LN ONLY
2 RIGHT LNS

LFT

Keep, Next—

NEXT LFT

LFT

—

Lane

LFT LANELOC TRAFFIC ONLY

Lane(s) (travel lanes ofa highway)
Left
Local

LOC

—

Traffic

Lower

LWR

—

Level

LWR LEVEL

Maintenance

MAINT

—

—

ROAD MAINT

Major

MAJ

—

Crash

MAJ CRASH

Minor

MNR

—

Crash

MNR CRASH

Normal

NORM

—

—

—

NORTH

Route Number, Road Name—

US 1 NORTH

N-BND

—

Lane, Traffic

N-BND TRAFFIC

Oversized

OVRSZ

—

Load

OVRSZ LOAD

Parking

PKING

—

—

—

Pavement

PVMT

Icy

—

ICY PVMTPreparePREP—

To Stop

PREP TO STOP

Quality

QLTY

Air

—

AIR QLTY

RT

Keep, Next—

KEEP RT

RT

—

Lane

RT LANERD WK 1 MILE

Northbound

Right
Road Work

RD WK

—

Ahead, [Distance]

Route

RTE

Best

—

BEST RTE

Service

SERV

—

—

SERV AREA OPEN

Shoulder

SHLDR

—

—

SHLDR CLOSED

Sect. 1D.08

December 2023

MUTCD 11th Edition

Page 37

Table 1D-2. Abbreviations that Shall be Used Only for
Temporary Messages on Portable Changeable Message Signs (Sheet 2 of 2)
Word Message
SlipperySouthbound
SpeedStandard
Abbreviation

Prompt Word
Preceding theAbbreviation

Prompt Word
Following theAbbreviation

Example

SLIP

—

—

—

SOUTH

Route Number, Road Name—

CA 1 SOUTH

S-BND

—

Lane, Traffic

S-BND TRAFFIC

SPD

—

—

SPD LIMIT[Route Abbreviation
determined by
highway agency]*—[Number]**

NY 7, CR 43

Tires With Lugs

LUGS

—

—

—

Traffic

TRAF

—

—

—

State, County, or othernon-U.S. or non-Interstate
numbered route

Travelers

TRVLRS———

Two-Wheeled Vehicles

CYCLES

—

—

—

UPR

—

Level

UPR LEVEL

Upper

US*

—

[Number]**

US 202

Vehicle(s)U.S. Numbered Route

VEH, VEHS———

Warning

WARN

—

—

—

WestboundWill Not

WEST

Route Number, Road Name—IL 53 WEST

W-BND

—

Lane, Traffic

W-BND LANES

WONT

—

—

—

* Abbreviation, when accompanied by the prompt word, may be used on traffic control devices other than portable message signs.
See Table 1D-1 for uses and format.
** A space and no hyphen shall be placed between the abbreviation and the number of the route.
Note: See Chapter 2L of this Manual for additional information on changeable message signs.

Table 1D-3. Unacceptable Abbreviations

December 2023

Abbreviation

Intended
Word

CommonMisinterpretation

ACC

Accident

Access (Road)

CLRS

ClearsColors

DLY

Delay

Daily

FDR

FeederFederalLane (Merge)

L

Left

LT

Light (Traffic)

Left

PARK

Parking

Park

POLL

Pollution (Index)

Poll

RED

ReduceRed

STAD

StadiumStandard

WRNG

Warning

Wrong

Sect. 1D.08

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MUTCD 11th Edition

Section 1D.09 Placement and Operation of Traffic Control Devices

Standard:
01
Before any highway, site roadway open to public travel (see definition in Section 1C.02), detour, or
temporary route is opened to public travel, all traffic control devices necessary for safe operation shallbe in place.
Option:02
Temporary traffic control devices, as provided for in Part 6 of this Manual, may be used in place of permanent
devices that have yet to be installed for safe operation.
Guidance:
03
Placement of a traffic control device should be within the road user’s view so that adequate visibility isprovided. To aid in conveying the proper meaning, the traffic control device should be appropriately positioned
with respect to the location, object, or situation to which it applies. The location and legibility of the traffic
control device should be such that a road user has adequate time to make the proper response in both day andnight conditions.
04
Traffic control devices should be placed and operated in a uniform and consistent manner as part ofmaintaining uniformity in traffic control.
Support:05
Inconsistent placement or use of a device can result in disrespect for the device at locations where the device
is needed and appropriate.
Guidance:
06
Unnecessary traffic control devices should be removed. The fact that a device is in good physical condition
should not be a basis for deferring needed removal or change.
Support:07
Section 2A.02 contains information on excessive use of signs and other considerations that can reduce theireffectiveness and the effectiveness of other traffic control devices.

Section 1D.10 Maintenance of Traffic Control Devices

Guidance:
Functional maintenance of traffic control devices should be used to determine if certain devices need to bechanged to meet current traffic conditions.
02
Physical maintenance of traffic control devices should be performed to retain the legibility and visibility ofthe device, and to retain the proper functioning of the device.
Support:03
Clean, legible, properly-mounted devices in good working condition command the respect of road users.
01

Section 1D.11 Crashworthiness of Traffic Control Devices and Other Roadside AppurtenancesStandard:
In accordance with various Sections of this Manual, certain traffic control devices and their supports,
and/or related appurtenances shall be crashworthy (see definition in Section 1C.02). Crashworthinessprovisions in this Manual shall apply to all streets, highways, and site roadways open to public travel.
Support:02
Roadside appurtenances include permanent and portable sign supports, other permanent or temporary traffic
control devices, and other roadside fixtures that are not traffic control devices, such as longitudinal barriers, bridge
railings, and crash cushions, within the clear zone. Crashworthiness of a device or appurtenance is determined bynationally established standards such as the “Manual for Assessing Safety Hardware” (MASH), 2016, AASHTO.
Information on the FHWA’s policy on crashworthiness of devices on the National Highway System and otherroadways is available at the FHWA Office of Safety Web site at https://safety.fhwa.dot.gov/roadway_dept/countermeasures/reduce_crash_severity/policy_memo_guidance.cfm.
01

Sect. 1D.09 to 1D.11

December 2023