Interpretation Letter 6(09)-18 (I) — Use of a Sequential or Flashing Arrow Board Display on a PCMS

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U.S. Department of Transportation
Federal Highway Administration

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

December 4, 2012

In Reply Refer To: HOTO-1

Bill Wondrachek, Jr., P.E.
Statewide Traffic Incident Management Engineer
Wisconsin Department of Transportation
433 West St. Paul Avenue, Suite 300
Milwaukee, WI 53203

Dear Mr. Wondrachek:

Thank you for your inquiry of November 20 requesting an official interpretation of the provisions in Sections 6F.60 and 6F.61 of the 2009 Manual on Uniform Traffic Control Devices (MUTCD) regarding the use of a portable changeable message sign (PCMS) to simulate an arrow board display. Specifically, you are asking if including a sequential arrow display on a PCMS would violate Paragraph 19 in Section 6F.60 — Portable Changeable Message Signs, which states:

Techniques of message display such as animation, rapid flashing, dissolving, exploding, scrolling, travelling horizontally or vertically across the face of the sign, or other dynamic elements shall not be used.

The intention of Paragraph 19 is to prohibit the use of special effects to grab the attention of the road user as they approach the PCMS. Although the special effects listed in this paragraph might succeed in drawing the attention of motorists, unfortunately these effects also tend to distract from the message itself and might make the sign less effective overall.

Paragraph 26 in Section 6F.61 (Arrow Boards) says, "A portable changeable message sign may be used to simulate an arrow board display." Some of the sequential or flashing modes that are permitted on arrow boards (see Figure 6F-6 in the 2009 MUTCD) include some of the message display techniques that are prohibited in Paragraph 19 in Section 6F.60. Thus, Paragraph 26 in Section 6F.61 appears to be inconsistent with Paragraph 19 in Section 6F.60.

It is the FHWA's official interpretation that when a PCMS is being used to simulate an arrow board that the display on the PCMS of a sequential or flashing mode that is permitted on an arrow board would not violate Paragraph 19 in Section 6F.60 and would be acceptable for use.

We plan to propose in the next Notice of Proposed Amendments the elimination of this apparent inconsistency by adding "Except when being used to simulate an arrow board display (see Section 6F.61)," to the beginning of Paragraph 19 in Section 6F.60.

For recordkeeping purposes, we have assigned the following official interpretation number and title: "6(09)-18 (I) — Use of a Sequential or Flashing Arrow Board Display on a PCMS." Please refer to this number and title in any future correspondence regarding this topic.

Thank you for your interest in improving the clarity of the provisions contained in Chapter 6F of the MUTCD. Please contact Mr. Ken Wood at ken.wood@dot.gov or 708-283-4340 if you have any further questions concerning this matter.

Sincerely yours,

Original signed by:

Mark R. Kehrli
Director, Office of Transportation Operations