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U.S. Department of Transportation

Federal Highway Administration

1200 New Jersey Avenue, SE.
Washington, DC 20590

September 17, 2008

In Reply Refer To: HSSD/CC-42B

Mr. Barry Stephens
Energy Absorption Systems, Inc.
3617 Cincinnati Avenue
Rocklin, CA 95765

Dear Mr. Stephens:

This letter is in response to your request for Federal Highway Administration (FHWA) acceptance of a roadside safety device for use on the National Highway System (NHS).

You requested that we find this device acceptable for use on the NHS under the provisions of National Cooperative Highway Research Program (NCHRP) Report 350 “Recommended Procedures for the Safety Performance Evaluation of Highway Features.”

Requirements

Roadside safety devices should meet the guidelines contained in the NCHRP Report 350, FHWA Memorandum “Action: Identifying Acceptable Highway Safety Features” of July 25, 1997, provides further guidance on crash testing requirements of longitudinal barriers.

Description

The QuadGuard, QuadGuard-Wide, and QuadGuard High Speed crash cushions have been tested and found acceptable in the FHWA Acceptance Letters noted below.

Crash Testing

No actual crash tests were submitted for this request. Instead, results from previous successful tests of parallel-sided and flared QuadGuards (QG and QG-Flared) at TL-3 impact speeds were presented as well as tests into a parallel-sided QuadGuard high speed unit at elevated impact speeds of 70 mph (QG-HS). Using the data from those successful tests, engineering logic was presented predicting the results for similar tests into your proposed High Speed Quad Guard – Flared Version.

The following is a brief summary of the NCHRP Report 350 non-gating crash cushion tests that were evaluated in your analysis:

Findings

As a service to the highway community, FHWA finds devices meeting NCHRP Report 350 acceptable for use on the National Highway System for impact speeds up to 100 km/hr. You have shown that the QG-HS-Flared will likely meet similar evaluation criteria when tested at 113 km/hr. FHWA concurs that the device described above and detailed in the enclosed drawing is acceptable for use on the NHS under NCHRP Report 350 TL-3 conditions, when acceptable to a highway agency. Should an agency wish to specify an attenuator with capacity exceeding TL-3 the QG-HS-Flared is acceptable for use at speeds up to 113 km/hr.

Please note the following standard provisions that apply to FHWA letters of acceptance:

 

Sincerely yours,

Signature of David A. Nicol

David A. Nicol
Director, Office of Safety Design
Office of Safety

Enclosures


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