911.1 General (MUTCD Chapter 1A)

911.1.1 Purpose of the MUTCD (MUTCD Section 1A.01)

Support. MoDOT bases all traffic control device policies on the National MUTCD as it is the national standard. The information in EPG 911 is directly from the National MUTCD with minimal modifications.

Contact the Highway Safety and Traffic Division for all official interpretations, experiments, changes to the National MUTCD, or interim approvals.

The purpose of the MUTCD is to establish uniform national criteria for the use of traffic control devices that meet the needs and expectancy of road users on all streets, highways, pedestrian and bicycle facilities, and site roadways open to public travel.

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; and

D. Provide basic principles for traffic engineers to use in making decisions regarding the use, installation, operation, maintenance, and removal of traffic control devices.

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 in recognition 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.

The use of uniform traffic control devices also requires uniform and appropriate application.

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).

This Manual presumes the user of the MUTCD has sufficient working knowledge, professional training and experience, and education in the principles of traffic engineering. Other resources can be consulted to understand the basis for decisions that are made in which engineering study or judgment will be applied.

911.1.2 Traffic Control Devices – General Description (MUTCD Section 1A.02 )

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.

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.

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 and provisions 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 photo enforcement 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; and

E. Signs giving civic organization meeting information.

911.1.3 Target Road Users (MUTCD Section 1A.03)

Support. Traffic control devices can be targeted at operators of motor vehicles, including driving automation systems, and at vulnerable road users.

Targeted operators of motor vehicles include motorists, public transportation operators, truck drivers, and motorcyclists. 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, or other impairments. Protection of vulnerable users is a priority in this Manual as directed in Section 11135 of the Infrastructure Investment and Jobs Act.

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 on these roadways requires careful consideration of measures to set and design for appropriate speeds; separation of various 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.

911.1.4 Use of the MUTCD (MUTCD Section 1A.04)

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. Where the content of this Manual requires a decision for implementation, such decisions shall be made by 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. Section 1C.02 contains definitions of “engineering study” and “engineering judgment.”

Guidance. In making traffic control device decisions, individuals should consider the impacts of the decision on the following: 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. Throughout this Manual the headings Standard, Guidance, Option, and Support, the meanings of which are defined in Section 1C.01, are used to classify the nature of the text that follows. Figures and tables, including the notes 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. 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 be appropriately altered to fit the specific situation.

Similarly, destination names, route numbers, and State route shields that are displayed on the images of devices 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. The information contained in the following paragraphs will be useful when reference is being made to a specific portion of text in this Manual.

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 of Regulatory Signs.” In some Chapters, the Sections are grouped together by subject into unnumbered sub-chapters with a heading, such as “Signing for Right-of-Way at Intersections” (for Sections 2B.06 through 2B.20).

Each 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. Some paragraphs have lettered or numbered items. As an example of how to cite this Manual, the phrase “[n]ot less than 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.”

911.1.5 Relation to Other Publications (MUTCD Section 1A.05)

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. The “Standard Highway Signs” publication includes standard alphabets and symbols and arrows for signs and pavement markings.

The MUTCD is not a roadway design manual, and engineers seeking guidance on design should refer to appropriate roadway design guides recognized by the Federal Highway Administration as needed for the design application.

Other publications are referenced in this Manual as useful resources, but they are not regulatory in nature and are not independently legally enforceable.

911.1.6 Uniform Vehicle Code – Rules of the Road (MUTCD Section 1A.06)

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 is to promote national uniformity in these laws. The Rules of the Road contained in the UVC are intended to be recommendations for States to adopt in their State statutes and are not independently legally enforceable.

Guidance. 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.”