May 26, 2005
In Reply Refer To: HSA-10/CC-73B
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 May 6 letter to Mr. Richard Powers of my staff. In this letter you requested the Federal Highway Administration (FHWA) acceptance of two new versions of a low speed test level 2 (TL-2) Wide REACT. These units are patterned after the TL-3 Wide REACTs previously accepted by our office (reference acceptance letters HSA-10/CC-73 and CC-73A). To support your request, you included a report (NCHRP Report 350 Crash Test Results for the TL-2 Wide REACT 350 System Revision A, dated May 2005) and videotapes prepared by E-Tech Testing Services that describes the TL-2 crash tests conducted into a 2440-mm wide TL-2 REACT. As a reference, you also included copies of reports for the previously accepted TL-3 Wide REACTs.
The TL-2 Wide REACTs are intended to be redirective, non-gating crash cushions having an effective length of 5.34 m and are designed to shield wide hazards. They can be configured with backup widths of 1524 mm (60) or 2440 mm (96). These two designs are shown in Enclosure1. Because these TL-2 REACTs have essentially the same framework and components as the previously accepted TL-3 Wide REACTs, we agree that the redirect capacity of the new TL-2 tests is validated by the successful results from your previous TL-3 tests. We also agree that the two tests you conducted into the new TL-2 unit, tests 2-31 and 2-32(modified), are the most critical to validate the frontal capacity of the TL-2 unit for light and heavy vehicles. Summary sheets for each of these tests are shown in Enclosure 2. Our review of the submitted test report confirms that the tested TL-2 REACT, with a width of 2440 mm (96), met all the appropriate NCHRP 350 evaluation criteria for redirective, non-gating crash cushions. You state the 1534 mm (60) wide unit is essentially the same as the tested 2440 mm version and has the same energy dissipating elements. The primary difference is the width of the unit. As a consequence, we agree that the 1534 mm wide version will perform essentially the same as the 2440 mm wide version.
Based on our review, we agree that the tested 2440 mm wide REACT system meets the evaluation criteria for an NCHRP Report 350 redirective, non-gating crash cushion at TL-2 impact conditions and may be used on the National Highway System (NHS) when such use is acceptable to the contracting authority. We also agree that the similar 1534 mm wide REACT, made from essentially the same components, and any intermediate width design may also be considered a TL-2 crash cushion without need for additional testing.
Please note also that the following provisions apply to the FHWA letters of acceptance: