Manual on Uniform Traffic Control Devices (MUTCD) arrows logo

Interpretation Letter 3(09)-6 (I) - Word and Symbol Markings – Stencil Gaps

PDF Version, 72KB

You will need the Adobe Acrobat Reader to view the PDF on this page.



DOT Logo

U.S. Department of Transportation
Federal Highway Administration

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

March 23, 2011

In Reply Refer To: HOTO-1

Mr. Merritt K. Rogers
President
PROMARK, Inc.
P.O. Box 1685
Lolo, MT 59847

Dear Mr. Rogers:

Thank you for your March 16 letter requesting an official interpretation of the Manual on Uniform Traffic Control Devices (MUTCD) regarding stencil gaps in word message and symbol pavement markings. You asked whether it is acceptable for word message, arrow, and symbol markings installed with stencils to have gaps in the letters or symbols.

It is our Official Interpretation that arrows, symbol markings, and letters and numbers used for word messages that are applied to the pavement using stencils rather than preformed materials may have small gaps as long as the highway agency determines via engineering judgment that such gaps do not materially compromise the legibility or conspicuity of the message being conveyed by the markings. Our reasoning for this interpretation is as follows.

The MUTCD does not specifically address the issue of gaps in these types of markings. However, it has been a very longstanding practice by highway agencies and markings installation companies to form these markings by placing a stencil on the pavement and then applying traffic paint onto the open areas of the stencil. This type of installation practice was prevalent prior to the development of newer materials that enabled solid preformed letters and symbols to be applied, but stencils are still used extensively for markings installation and maintenance.

As a practical manner, large open areas of the stencils are typically broken up by connecting pieces of the metal or other material of which the stencil is made, to give stability to the stencil and thus prevent it from becoming misshapen or broken while in use. The breaks in the stencil result in gaps in the traffic paint applied to the pavement and thus the arrow, symbol, letters, or numbers are not fully solid but have one or more small gaps in them.

We believe that the stencil gaps in such markings ordinarily do not cause degradation in visibility, legibility, or road user understanding of the meaning of the message. The gaps are usually more of an aesthetic matter that some highway agencies may prefer to avoid, and they may do so via their detailed specifications for markings. Highway agencies have the authority to determine, on the basis of engineering judgment, whether stencil gaps are allowed or prohibited for their markings and, if they are allowed, the precise details of which letters, numbers, arrows, or symbols may have gaps and what the maximum allowed gap size is.

Thank you for writing on this subject. We hope that our interpretation answers your question. Please note that we have assigned your request the following official interpretation number and title: "3(09)-6 (I) – Word and Symbol Markings – Stencil Gaps." Please refer to this number in any future correspondence regarding this issue.

Sincerely yours,

Original signed by:

Hari Kalla for

Mark R. Kehrli
Director, Office of Transportation Operations

Incoming Letter