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Interpretation Letter 2-669(I) - National Scenic Byway Signing

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Contact Information: Operations Feedback at

U.S. Department of Transportation Federal Highway Administration

1200 New Jersey Avenue, SE.
Washington, D.C. 20590

November 30, 2009

In Reply Refer To: HOTO-1

Mr. Mark W. Bott
Traffic Operations Manager
Michigan Department of Transportation
P.O. Box 30050
Lansing, MI 48909

Dear Mr. Bott:

Thank you for your October 22 letter requesting interpretation of the provisions of the Manual on Uniform Traffic Control Devices (MUTCD) regarding signing for National Scenic Byways and a unique sign designating a heritage route in Michigan. We have determined that the lower portion of the sign proposed for the Woodward Avenue Automotive Heritage Trail scenic byway route does not conform to the requirements of the MUTCD for the signing of a National Scenic Byway. As Woodward Avenue has been designated a trail by the State of Michigan, the upper portion of the subject sign falls under the MUTCD provisions for Trail signs, sometimes referred to as Auto Tour Route signs. Please be advised that the signing of designated trails is a topic under consideration in an active rulemaking for the next edition of the MUTCD. A detailed explanation of this official ruling is provided herein.

  1. The provisions for use of the National Scenic Byways sign in Section 2D.52 of the MUTCD are clear. The MUTCD requires that the National Scenic Byways sign, when used, shall be of one of the designs designated as D6-4 or D6-4a. Although it might be argued that the National Scenic Byways sign itself is not being used because only the official National Scenic Byways pictograph has been incorporated as an integral element of a Trail or Auto Tour Route sign, the effect is a design that is different from the standard sign, as the National Scenic Byways pictograph constitutes the principal legend of the standard sign designs. The primary issue is the deviation in the color arrangement and contrast orientation of the National Scenic Byways pictograph.
  2. We do not agree that the proposed sign design addresses the issue raised concerning sign clutter. Further, we do not concur that the use of the standard National Scenic Byways sign design would contribute to sign clutter. Sign clutter is the proliferation of sign installations or assemblies along the roadway or roadside, either separately or grouped, to such an extent that adequate spacing between installations necessary for orderly processing of the sign messages cannot be achieved without unduly distracting the attention of the motorist away from the driving task. The National Scenic Byways sign is installed either independently or as part of a route assembly. Whether the Byways pictograph is incorporated as an integral legend element of the Woodward Avenue trail sign or whether it is a separate sign in the same assembly or on the same substrate, the effect on sign clutter would be neutral.
  3. The official designs of the National Scenic Byway signs (D6-4 and D6-4a) do not contain the registered trademark symbol. Use of the registered trademark symbol is not appropriate on a traffic control sign as this information is indiscernible in a dynamic driving environment and is inconsequential to road user navigation and guidance.
  4. Please be advised that the proposed provisions for Trail signs published in the January 2, 2008, Notice of Proposed Amendments to the MUTCD are subject to an upcoming rulemaking for the new edition of the MUTCD. This NPA states that Trail signs, when in the form of a shield or similar design, should be designed in accordance with the sizes and other design principles for route signs. It is not known at this time to what extent the proposed provisions might or might not be adopted for a final rule. Further, the proposed graphic is very finely detailed. We suggest that this design be further evaluated qualitatively for visibility and recognition when viewed in a dynamic driving environment.
  5. Among the criteria for any traffic sign is the requirement that it be retroreflectorized to display the same shape and color by both day and night. The gradation of the background color of the proposed sign might be difficult or might not be commercially available in a retroreflectorized medium. This aspect of the sign design should be considered in the context of the requirement for retroreflectivity.
  6. The purpose of a traffic control device is to regulate, warn, guide, or otherwise control traffic. The fundamental purposes of traffic control devices do not include branding or the establishment of identity by virtue of their design. Rather, these purposes are more appropriately served by other media, such as recommended in MUTCD Section 2D.50 which states, "primary guidance should be in the form of printed literature and strip maps rather than trail signing." In this regard, any design and placement of Trail signs must be limited to those that are essential for road user navigation and guidance. In no case should a Trail sign take precedence over or be considered a replacement for a route sign or directional guide sign.

We appreciate the opportunity to provide this interpretation and hope that you find it helpful in developing a Trail sign that serves the needs of road users and conforms to the basic principles of traffic control devices. We have assigned this interpretation the following official ruling number and title: "2‐669 (I)—National Scenic Byway Signing—Michigan." Please refer to this number and title in future correspondence. If you have questions or wish additional information, please contact Mr. Kevin Sylvester at 202-366-2161.

Sincerely yours,

Original signed by Hari Kalla (for)

Paul Pisano
Acting Director, Office of Transportation Operations

cc: Mr. Gary Jensen, FHWA