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Safety Eligibility Letter B-97A

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U.S. Department of Transportation
Federal Highway Administration

1200 New Jersey Ave. S.E.
Washington, D.C. 20590

April 4, 2008

In Reply Refer To: HSSD/B-97A

Mr. Leo J. Yodock, III
1000 Market Street
Bloomsburg, PA 17815

Dear Mr. Yodock:

This letter is in response to your request for Federal Highway Administration (FHWA) acceptance of a modified roadside safety system for use on the National Highway System (NHS).

Name of system: Yodock Barrier Wall
Type of system: Water Filled Barrier Models 2001 and 2001M
Test Level: Model 2001: TL-3; Model 2001M: TL-2
Testing conducted by: Texas Transportation Institute
Date of request: August 27, 2007
Date of follow-up: March 27, 2008

You requested that we find this system acceptable for use on the NHS under the provisions of National Cooperative Highway Research Program (NCHRP) Report 350 “Recommended Procedures for the Safety Performance Evaluation of Highway Features.”

Roadside safety systems should meet the guidelines contained in the NCHRP Report 350, "Recommended Procedures for the Safety Performance Evaluation of Highway Features". FHWA Memorandum “ACTION: Identifying Acceptable Highway Safety Features” of July 25, 1997 provides further guidance on crash testing requirements of longitudinal barriers.

The Yodock Barrier Wall is comprised of 1170-mm long low-density polyethylene units that are 1170-mm tall, 610-mm wide at the base, and 280-mm wide at the top. The individual units are connected at the ends with polyethylene couplers and along the sides by 89 mm x 89 mm x 6.4 mm structural steel tubes supported by steel brackets which extend through two forklift holes in each unit. These tubes are mounted at a centerline height of 706 mm. In the original design the structural steel tubes rested on 102-mm square wood blocks. Your present request is to replace the wood block design with an all-steel bracket assembly as shown on the enclosed drawings.

You are in the process of developing a permanently installed configuration but wish to gain FHWA acceptance for this modification of the support bracket. To support this request you sent drawings, video of the test, and the test data summary sheet. Mr. Nicholas Artimovich of my staff verbally concurred in this design change on August 10, 2007, and you subsequently requested formal documentation. The full crash test report will be submitted when your present development efforts have been completed.

Crash Testing
A 30.6-meter long Yodock Water Cell Barrier was subjected to NCHRP Report 350 test 3-11. The pickup was successfully contained by the system which had a deflection of 4.09 m. The results of the test are summarized in the enclosed test data summary sheet.

The test met the requirements of the FWHA and NCHRP Report 350. Therefore the requested modification is acceptable for use on the NHS, when permitted by a highway or transportation authority, under the range of conditions the original design was tested.

Please note the following standard provisions that apply to FHWA letters of acceptance:


Sincerely yours,

Signature of David A. Nicol
David A. Nicol
Director, Office of Safety Design
Office of Safety

Page last modified on August 16, 2011.
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