Safety Eligibility Letter B-85C
Safety Eligibility Letter B-85C
U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Ave. S.E.
Washington, D.C. 20590
January 10, 2003
HSA-10/B85-C
Mr. Rodney A. Boyd
Trinity Highway Safety Products Division
Box 568887
Dallas, Texas 75356-8887
Dear Mr. Boyd:
In your December 17, 2002, letter to Mr. Richard Powers of my staff you requested acceptance of a recycled plastic offset block (King Sized King Block) for use with Thrie-beam guardrail. You stated that the larger block is identical in material composition and has the same physical features as your currently-accepted King block, except for its increased nominal length of 554mm (22 inches) and the addition of a second set of bolt holes. These and other design details are shown in the enclosure to this letter.
Based on the results of the pendulum tests conducted at Southwest Research Institute and reported in that agency’s December 12, 2002, test report, “Impact Evaluation of a Recycled Plastic/Rubber Composite Blockout – Test KB-110”, I find the King Sized King Block to be acceptable for use with strong steel post Thrie-beam guardrail on the National Highway System.
Sincerely yours,
Harry W. Taylor |
Enclosure