July 16, 1997

Refer to: HNG-14

J. M. Essex, P.E.
Vice President, Sales
Energy Absorption Systems, Inc.
One East Wacker Drive
Chicago, Illinois 60601

Dear Mr. Essex:

In your June 5 letter to Mr. Gerald L. Eller you requested the Federal Highway Administration (FHWA) to accept the six-bay QuadGuard-Wide system as a non-gating, redirective crash cushion meeting the recommendations in the National Cooperative Highway Research Program (NCHRP) Report 350 for a Test Level 3 (TL-3) device. In support of this request, you provided copies of your June 1997 report, "QuadGuard-Wide System Qualification to NCHRP 350, Engineering Summary." This report included information on six tests conducted by E-TECH Testing Services, Inc., under NCHRP Report 350 guidelines and was bound with an E-TECH report on the tests. These were NCHRP Report 350 tests 3-30, 3-31, 3-32, 3-33, 3-37, and 3-39. You also submitted drawings of the new design, and photographs and videotapes of the six tests that had been run.

After reviewing this information, members of my staff informed you that passing results from tests 3-36 and 3-38 would be needed before we could accept your product. We received summary data on the two additional tests on June 27 and a revised summary and test report containing data on all of the tests on July 8.

The QuadGuard-Wide system is a flared design intended to shield hazards that are 1766 mm wide or 2286 mm wide, compared to the 914-mm wide, parallel-sided QuadGuard crash cushion. The QuadGuard-Wide system uses several parts identical to those used in the original QuadGuard, such as Quad Beam fender panels, monorail and monorail guides, diaphragm leg assemblies, Type I and Type II cartridges, nose wrap, and system anchorage.

Design features specific to the QuadGuard-Wide system include progressively wider diaphragms from the front to the back of the system, pivot connection points for the fender panels, and a modified mushroom bolt assembly to hold the overlapping fender panels together. The tested unit consisted of six bays and was 6740-mm long. Enclosure 1 includes a drawing of the 2286-mm wide design (which was used for all tests except 3-39, where the 1766-mm wide unit was used), a copy of its general specifications, and sketches of the developmental and final versions of the variable-width diaphragms and backup structures. Enclosure 2 contains summary reports of the eight tests that were conducted on the QuadGuard-Wide system.

Based on our review of the information you submitted, we have concluded that the six-bay QuadGuard-Wide system, with either the 1766-mm or 2286-mm wide configuration, meets the NCHRP Report 350 evaluation criteria for a TL-3 attenuator and may be used on the National Highway System (NHS) when selected by a highway agency. Since it is a proprietary product, all regulations regarding its use on Federal-aid projects (except exempt non-NBS projects) remain applicable.

A copy of this letter and its enclosures will be sent to the FHWA field offices for information.

2 Enclosures