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Safety Eligibility Letter B-208

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U.S. Department of Transportation
Federal Highway Administration

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

December 29, 2010

In Reply Refer To:

Mr. Wolfgang Wink
Volkmann and Rossbach
Hohestrasse 11-19
D-5601 Montabaur, Germany

Dear Mr. Wink:

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

Name of system: VarioGuard “C” Freestanding Barrier
Type of system: Steel roadside and median barrier
Test Level: NCHRP Report 350 Test Level 3 (TL-3)
Testing conducted by: TRL, United Kingdom
Task Force 13 Designator: SGM30
Date of request: July 28, 2010
Date initially acknowledged: September 9, 2010
Date of completed package: December 20, 2010

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

The following device was found acceptable, with details provided below:

Roadside safety devices should meet the guidelines contained in the NCHRP Report 350 or the American Association of State Highway and Transportation Officials’ Manual for Assessing Safety Hardware. The FHWA memorandum ‘Identifying Acceptable Highway Safety Features” of July 25, 1997, provides further guidance on crash testing requirements of longitudinal barriers.

The VarioGuard “C” is a portable 900-mm tall steel barrier consisting of the following four principal elements:

  1. A 2.5 mm-thick shell
  2. A 700-mm wide by 378-mm tall base unit
  3. 855-mm long intermediate posts
  4. A 180-mm wide by 150-mm tall box beam top rail

The barrier’s narrow profile allows it to be used where lane-width is at a premium while its wide base provides stability when impacted. Drawings of the VarioGuard “C” are enclosed for reference.

Crash Testing
The VarioGuard barrier had been tested in Europe to meet the CEN standard “H2 of DIN EN 1317-2.” H2 consists of the following tests:

While the H2 small car test is comparable to the 820C test of NCHRP Report 350, the truck test greatly exceeds the severity of both the NCHRP Report 350 2000P TL-3 impact (Test 3-11) and the 8000S impact (Test 4-12) for TL-4. This testing showed that the VarioGuard had the strength to redirect a large truck, however, FHWA requested the NCHRP Report 350 Test 3-11 be run in order to demonstrate performance with the 2000P pickup truck, a relatively unstable vehicle in barrier crash tests.

The NCHRP Report 350 Test 3-11 was conducted in substantial conformity with the NCHRP Report 350 by the Transport Research Laboratory in the United Kingdom. The test article consisted of 25 sections of 12-meter long VarioGuard “C” quick jointed barriers. The units were connected with a single M16 bolt. Each 12-m unit consisted of three 4-m long sections that were bolted together. The complete installation was 300 meters long and was completely free-standing with no terminal pins at the ends of the barrier. All occupant risk factors were met, and the permanent and dynamic deflections were measured at 2.92 meters. The working width was determined to be 3.62 meters. The test data summary sheet is enclosed for reference.

The system described in the requests above and detailed in the enclosed drawings is acceptable for use on the NHS under the range of conditions tested, when such use is acceptable to a highway agency.

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


Sincerely yours,

/* Signature of Michael S. Griffith */

Michael S. Griffith
Director, Office of Safety Technologies
Office of Safety


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