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June 3, 1996

Refer to: HNG-14/SS-62

Mr. Nick D. Calvi
National Signpost Representative
Western Highway Products, Inc.
Traffic Signs and Safety Products
10650 Fern Avenue
Stanton, California 90680

Dear Mr. Calvi:

This is in response to your March 19 letter to Mr. James H. Hatton, Jr., requesting acceptance of your company's Ulti-Mate telescopic square steel sign supports. In support of your request you included information on the geometric, chemical, and physical properties of the posts which indicate that they will be in reasonable close conformity with perforated square steel tube sign supports that we have previously found acceptable by virtue of full-scale crash testing. The 7/16-inch (11.1 mm) perforations punched 1-inch (2.54-mm) on-center on all four sides are identical to those on perforated square steel tube breakaway sign supports previously found acceptable.

On April 29 you provided a copy of a mill certification for the steel you intend to use in the fabricated tubes (ASTM A513-94, Grade 1012). The results compared favorably with the steel usually specified for these supports, namely the ASTM A653-94 specifications cited in the table below (A653 replaced the steel tube specification that was used in the past, namely A446.) The following table summarizes the sizes and materials you intend to use:

Wall Thickness

14 Gage (2.10 mm, 0.083 in)

12 Gage (2.66 mm, 0.105 in)

Steel (ASTM Specification)

A653-94 SQ Grade 50 modified to “Grade 55”

A653-94 SQ Grade 40

Sizes (SI units) mm

44.45, 50.80, 57.15

38.10, 44.45, 50.80, 57.15, 63.50

Sizes (customary US units) inches

1.75, 2.00, 2.25

1.50, 1.75, 2.00, 2.25, 2.50

In addition, you requested the Federal Highway Administration's (FHWA) acceptance of several of these posts installed in a variety of configurations for use on National Highway System (NHS) projects. After reviewing our records of experience with similar posts we find that we can comply with your request. The post sizes and use conditions we will find acceptable for use on the NHS, if proposed by a State, are shown in the enclosed table.

Sincerely yours,

Seppo I. Sillan, Acting Chief
Federal-Aid and Design Division


Geometric and Roadside Design Acceptance Letter SS-62

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