Skip to contentSkip to contentUnited States Department of Transportation - Federal Highway Administration FHWA HomeFeedback

DOT logo
U.S. Department of Transportation

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
Vice President
Safence Inc.
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:

FHWA# Date NCHRP Cables Name     Spacing Deflection
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
B-88 7/13/2001 TL-3 480 630 780 930  
B-88A 1/28/2004 TL-3 480 560 640 720 3504RI
B-88B 6/8/2004 TL-3 480 560 640 720  
B-88C 5/26/2005 TL-3 480 630 780 930  
B-88D 12/27/2006 TL-4 480 640 720 (none) 3RC
B-88E This Letter TL-4 480 560 640 720  

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:

Sincerely yours,

Signature of Mary McDonough

for: George E. Rice
Acting Director, Office of Safety Design
Office of Safety

2 Enclosures

Safety Home | FHWA Home | Feedback