May 8, 2006
In Reply Refer To: HSA-10/CC-73C
Mr. Barry D. Stephens, P.E.
Sr. Vice President Engineering
Energy Absorption Systems, Inc.
3617 Cincinnati Avenue
Rocklin, California 95678
Dear Mr. Stephens:
Mr. Douglas Bernard recently delivered your April 19, 2006, letter to Mr. Richard Powers of my staff. In this letter you requested the Federal Highway Administration (FHWA) acceptance of a low-speed Wide REACT at NCHRP Report 350 test level 1 (TL-1). The configuration of this unit is similar to your TL-3 and TL-2 Wide REACT designs that have been previously reviewed and accepted by the FHWA (reference acceptance letters HSA-10/CC-73, CC-73A and CC-73B). To support your request, you included drawings of the new unit with widths of 60" and 96", a chart listing the kinetic energy dissipating capacities of common REACT cylinders used to assemble these systems and a figure listing the estimated energy-absorption capacities of your TL-2, TL-3 and proposed TL-1 units. Also included, as reference, were copies of one-page summaries from previously accepted (60"/96") TL-2 and (60"/96"/120") TL-3 Wide REACT tests.
The TL-1 Wide REACT is a redirective, non-gating crash cushion having an effective length of 3.23 m (10.6 feet). It can be configured with backup widths from 1524m (60") to 2440 (96") as shown in Enclosure 1. Because the TL-1 REACT has essentially the same framework and components as the previously accepted TL-2 and TL-3 Wide REACTs, we agree that the low-speed designs may be assumed to meet the National Cooperative Highway Research Program Report 350 evaluation criteria at TL-1 without additional testing and can be used on the National Highway System (NHS) when such use is acceptable to the contracting authority. However, it is critical that they be used only in locations where impact speeds are not expected to exceed 50 km/h (30 mph) or in locations where a higher-capacity, longer crash cushion cannot be installed due to space limitations.
Please note also that the following provisions apply to the FHWA letters of acceptance:
/original signed by/
John R. Baxter, P.E.
Director, Office of Safety Design
Office of Safety