Federal Highway Administration
400 Seventh St., S.W.
Washington, D.C. 20590
July 31, 2007
In Reply Refer To: HSSD-10/B-88E
Mr. Michael Kempen
46-04 245th Street
Douglaston, NY 11362
Dear Mr. Kempen:
Thank you for your letter requesting the Federal Highway Administration’s (FHWA) acceptance of your company’s four-cable tensioned barrier as a Test Level 4 device for use on the National Highway System (NHS). Accompanying your letter was a report of crash testing conducted by the Swedish Verg Traffik Institute and a consultant review of the system. You requested that we find this device 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.”
The FHWA guidance on crash testing of roadside safety hardware is contained in a memorandum dated July 25, 1997, titled “INFORMATION: Identifying Acceptable Highway Safety Features.”
Full-scale automobile, pickup, and single-unit truck testing has been conducted on your Safence cable barrier systems leading to the following FHWA Acceptance Letters:
|B-88||7/13/01||TL-3||4||Roadside||Driven elliptical posts||2.5||1.8|
|B-88A||1/28/04||TL-3||4||3504RI||Median||Driven I posts||2.5||2.7|
|B-88B||6/8/04||TL-3||4||Concrete footers||2 to 3||1.9 to 2.5|
|B-88C||5/26/05||TL-3||4||Roadside||Allow "C" posts||?||?|
|B-88D||12/27/06||TL-4||3||3RC||Modified C posts||10 m||3.7|
Cable heights in these systems are as follows:
|height 1||height 2||height 3||height 4||Name|
Your present request builds on prior testing of the 4-cable Safence systems to Test Level 3 and testing of the 3-Cable “3RC” system to Test Level 4. We concur that the addition of the fourth cable to the “3RC” system will have no adverse effect on the performance of this Test Level 4 barrier. The fourth cable is anchored with its own connection to the concrete terminal block.
Therefore, the Safence 4 cable system described above and detailed in the enclosed drawings is acceptable for use on the NHS under the range of conditions tested, when proposed by a State.
Other details of this system include:
Posts may be driven or placed in concrete footings.
Steel used in the 1230 mm long posts is ASTM A1011 HSLAS Grade 50
Cable tension at 100 F installation temperature is to be 1750 foot-pounds
Dynamic deflection of the system is 2.2 meters with the 8000S single-unit truck and 2.1 meters with the 2000P pickup truck.
Please note the following standard provisions that apply to FHWA letters of acceptance:
for: George E. Rice
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