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Interpretation Letter 2-547(I)-Relationship of the Terms Breakaway and Crashworthy

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U.S. Department of Transportation
Federal Highway Administration

400 Seventh St., S.W.
Washington, D.C. 20590

April 2, 2004

Refer to: HOTO-1

Ms. Sue Reiss
Regional Sales Manager
Impact Recovery Systems
P.O. Box 12637
246 West Josephine Street
San Antonio, TX 78212

Dear Ms. Reiss:

Thank you for your letter of February 10 requesting the Federal Highway Administration (FHWA) to consider replacement of the term "breakaway" with the term "yielding" or "crashworthy" in the Manual on Uniform Traffic Control Devices (MUTCD). For recordkeeping purposes, we have assigned your request the following official ruling number and title: "2-547(I)-Relationship of the Terms Breakaway and Crashworthy."

The definition of crashworthy is contained in Section 1A.13 of the MUTCD. This definition reads as follows: A characteristic of a roadside appurtenance that has been successfully crash tested in accordance with a national standard such as the National Cooperative Highway Research Program Report 350, "Recommended Procedures for Safety Performance Evaluation of Highway Features."

The 2002 AASHTO Roadside Design Guide (Chapter 4.1, Acceptance Criteria for Breakaway Supports) uses the term "breakaway" to describe all types of sign, luminaire, and traffic signal supports that are designed to yield when impacted by a vehicle. The Roadside Design Guide also indicates that the criteria used to determine if a support is considered breakaway can be found in the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals. The AASHTO specifications have been revised so that the breakaway requirements are identical to the crashworthy requirements in NCHRP Report 350.

Based upon the information provided above, it is our interpretation that breakaway and crashworthy are interchangeable terms. When the term breakaway is used, it means that the sign support is designed so that it breaks away safely-even in the case of a steel post. It is the intent of the FHWA for safety purposes to install traffic signs that are not only breakaway but to install traffic signs that are. also crashworthy. Therefore, we consider the terminology in the MUTCD to be correct and do not intend to change it at this time.

We appreciate your concern for highway safety and encourage you to continue making comments on the MUTCD. If you have questions or wish additional information, please feel free to call Fred Ranck, Safety Engineer, at 708-283-3545 at FHWA's Resource Center-Olympia Fields, Illinois.

Sincerely yours,

/s/ Ernest Huckaby for

Regina S. McElroy
Director, Office of Transportation Operations

IMPACT Recovery Systems

"Impacting Today's Roads for a Safer Tomorrow"

Sue Reiss
Regional Sales Manager
PO Box 12637
246 West Josephine St.
San Antonio, TX 78212
Phone (210) 385-0029
Fax (305) 946-0213

Tuesday, February 10, 2004

Regina. McElroy
Federal Highway Administration
HOTO-1, Room 3408
400 Seventh Street, SW
Washington, DC 20590 United States

Dear Regina:

This letter is written to address an issue contained in the new Section 2B. 12 IN-STREET PEDESTRIAN CROSSING SIGNS (RI-6, RI-6a).

Said section indicates "If the In-Street Pedestrian Crossing Sign is placed i nthe roadway, the sign support shall comply with the breakaway requirements of the latest edition of AASHTO's "Specification for Structual Supports for Highway Signs, Luminaries and Traffic Signals".

This wording would necessitate that any in-street pedestrian sign would be not only "breakaway", but by nature, contain a steel post. Such a requirement could compromise the safety of both the pedestrian and motorist and virtually eliminate the use of a safer, more commonly used sign support system.

The term "breakaway" normally does not ensure that the sign support is crashworthy, nor that it would meet NCHRP 350 test requirements.

Therefore, I would request that your Agency reconsider the terminology in the above-referenced section and consider replacing it with either "yielding" or "Cashworthy" in its place.

I look forward to hearing from you in this regard.


Sue Reiss