USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation
FHWA Highway Safety Programs

Safety Eligibility Letter SS-06

Hardware Type:
Sign Supports, Mailboxes, and Delineator Posts
Code:
SS-06
Date:
Testing Criteria:
NCHRP 350
Manufacturer:
Minute Man Anchors, Inc.
Device Description:
Breakaway coupling for use with steel flanged channel supports. **
View PDF:
ss06.pdf (496.67 KB)
Skip to contentUnited States Department of Transportation - Federal Highway Administration FHWA HomeFeedback

March 10, 1988

Refer to: HNG-14/SS-06

Mr. Albert M. Moreno, Sr.
Board Chairman
Minute Man Anchors, Inc.
305 West Walker Street
East Flat Rock, North Carolina 25726

Dear Mr. Moore:

Your December 28, 1987, letter requested Federal Highway Administration (FHWA) approval of a modified breakaway device for use with flanged steel sign supports. My January 29th reply expressed concern that the modified device was substantially different from a previously accepted design and that crash testing the new device was recommended to verify it’s impact performance.

On February 26 you sent a copy of a report showing that the new device performed acceptably in a 20 m.p.h pendulum test conducted by Southwest Research Institute. When extrapolated to 60 m.p.h using the procedure currently endorsed by FHWA, the results were also satisfactory. The changes in velocity for the 1,800 pendulum were 5.8 and 2.7 feet per second for the 20 m.p.h. (actual) and 60 m.p.h. (extrapolated) conditions, respectively. These results are below the current AASHTO breakaway specifications of 10 feet per second (desirable) and 15 feet per second (acceptable).

Based on the above information, the breakaway device sown on Drawing No. MMB-1 (copy enclosed) with revisions dated 12/15/87 and 1/26/88 is acceptable for use on Federal-aid projects if proposed by a State highway agency. Our calculations indicate that two such breakaway devices within an 8-foot path would produce a 13.8 feet per second change in velocity, thus meeting the maximum acceptable value of 15 feet per second.

The FHWA acceptance is limited to the breakaway characteristics of the system and does not cover its structural features. We assume that you will provide potential users with sufficient information on structural design and installation requirements to ensure proper support performance.

Sincerely yours,

L. A. Staron, Chief
Federal-Aid and Design Division

Enclosure

copies to: Regional Federal Highway Administrators, w/enclosure

FHWA Safety Home | FHWA Home | Feedback

FHWA

United States Department of Transportation - Federal Highway Administration