February 5, 2001
Mr. Richard Moore 								Refer to: HSA-B74A
Valley Rubber, L.L.C.
P.O. Box 1209
Hartselle, AL 35640-1209

Dear Mr. Moore:

In your January 23 letter to Mr. Richard Powers of my staff, you asked what procedures you would have to follow to modify the Valley Rubber guardrail offset blocks accepted for use on the National Highway System in my November 28, 2000 letter to you. Your proposed modification was be the addition of one hole as shown on Enclosure 1 to allow a four-inch adjustment in rail height. This adjustment is a common practice in some States in conjunction with roadway resurfacing and is unlikely to effect barrier performance. Therefore, the change may be considered acceptable.

You also asked if a larger block could be used. The external dimensions of the original Valley Rubber block were 114.3 mm x 158.8 mm x 355.6 mm (4.5 inches x 6.25 inches x 14 inches). The internal opening was 74.7 mm x 112.8 mm (2.9 inches x 4.4 inches) and the blockout included a 6.35 mm (.25 inch) protrusion along one vertical edge to prevent the block from rotating about the steel post flange. The larger block has external dimensions of 144.5 mm x 200 mm x 355.6 mm (5.7 in x 7.9 in x 14 in), an internal opening of 90.5 mm x 163.5 mm (3.6 in x 6.1 in) and a 6.35 mm (.25 in) deep x 95.3 mm (3.7 in) wide. Since this larger block is the standard size used by most States, the wall thicknesses have been increased, and the original, smaller block was successfully crash tested, the larger block, as shown in Enclosure 2, may be considered acceptable for use on the NHS.

You also asked if your product could be licensed to another company. The answer is yes, provided that appropriate quality control is in place to ensure that the blocks are composed of the same materials and molded to the same dimensions as the blocks that have been accepted for use on the NHS.

Sincerely yours,
(Original signed by Frederick G. Wright, Jr.)
Frederick G. Wright, Jr.
Program Manager, Safety

2 Enclosures