Safety Eligibility Letter CC-65F
Safety Eligibility Letter CC-65F
PDF [613 KB]
U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Ave. S.E.
Washington, D.C. 20590
April 20, 2011
In Reply Refer To: HSST/CC-65F
Mr. Felipe Almanza
TrafFix Devices Inc.
160 Avenida La Pata
San Clemente, CA 92673
Dear Mr. Almanza:
This letter is in response to your request for the Federal Highway Administration (FHWA) acceptance of a roadside safety device for use on the National Highway System (NHS).
Name of device: | Scorpion Truck Mounted Attenuator on lightweight shadow vehicle |
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Type of device: | Truck Mounted Attenuator |
Test Level: | NCHRP Report 350 Test Level 2 |
Testing conducted by: | Karco Engineering |
Date of request: | November 29, 2010 |
Complete package Rec’d: | December 1, 2010 |
Request acknowledged: | December 12, 2010 |
You requested that we find this system acceptable for use on the NHS under the provisions of the 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 or the American Association of State Highway and Transportation Officials’ Manual for Assessing Safety Hardware (MASH). The FHWA memorandum “Identifying Acceptable Highway Safety Features” of July 25, 1997, provides further guidance on crash testing requirements of longitudinal barriers.
Decision:
The following device is found acceptable:
- Test Level 2 Scorpion Truck Mounted Attenuator (TMA) on 4500 kg (9920 lb) shadow vehicle.
Description
The TrafFix Devices, Inc. Scorpion TMA is a crash cushion which mounts directly to a host vehicle’s rigid frame. It is comprised of three sections: (1) steel mounting section; (2) steel back-up section; and (3) aluminum cartridge section.
The steel mounting section provides a rigid attachment for the interface between the TMA and the host vehicle. The steel back-up section provides a structural mounting frame for the pivot location for the TMA to rotate to the vertical stored position when needed for transport. The aluminum cartridge section is comprised of structural energy absorbing curved aluminum tube framework, and three aluminum crush modules. The device has an overall length of 2.885 m (113.6 in) and overall width of 2.406 m (94.7 in). Enclosures 1 through 3 show the above components.
Crash Testing
The Scorpion TMA was crash tested by KARCO Engineering according to NCHRP 350 test designation 2-51 guidelines. Occupant impact velocities and occupant risk values were within allowable limits in this test. The test vehicle was not penetrated during the test. Enclosure 4 summarizes the results of test 2-51. In this test a 4497 kg (9914 lb) medium duty truck. It should be noted that the support vehicle roll-ahead distance in test 2-51 was measured 4121 mm (162 in, or 13-1/2 ft). Enclosure 5 illustrates movement of the support truck and deformation of the test article.
Findings
The Scorpion TMA described above was previously crash tested and accepted by FHWA for use on the NHS in acceptance letter CC-65 dated on July 14, 2000. In test 2-51 a 9000 kg
(19,842 lb) dump truck was used. For this current request letter, a smaller truck (4497 kg) was used for test 2-51. Results of the testing indicate that satisfactory results were obtained.
I concur with your request that the Scorpion TMA can be installed on vehicles weighing a minimum of 4500 kg (9920 lb). One element that highway agencies should be aware of when considering use of this product is the roll-ahead distance of 13-1/2 ft that was observed in the crash test.
Therefore, the device described above and detailed in the enclosed drawings is acceptable for use on the NHS under the range of conditions tested, when such use is acceptable to a highway agency.
Please note the following standard provisions that apply to FHWA letters of acceptance:
- This acceptance is limited to the crashworthiness characteristics of the devices and does not cover their structural features, nor conformity with the Manual on Uniform Traffic Control Devices.
- Any changes that may adversely influence the crashworthiness of the device will require a new acceptance letter.
- Should the FHWA discover that the qualification testing was flawed, that in-service performance reveals unacceptable safety problems, or that the device being marketed is significantly different from the version that was crash tested, we reserve the right to modify or revoke our acceptance.
- You will be expected to supply potential users with sufficient information on design and installation requirements to ensure proper performance.
- You will be expected to certify to potential users that the hardware furnished has essentially the same chemistry, mechanical properties, and geometry as that submitted for acceptance, and that it will meet the crashworthiness requirements of the FHWA and the NCHRP Report 350.
- To prevent misunderstanding by others, this letter of acceptance is designated as number CC-65F and shall not be reproduced except in full. This letter and the test documentation upon which it is based are public information. All such letters and documentation may be reviewed at our office upon request.
- Scorpion TMAs are patented products and considered proprietary. If proprietary devices are specified by a highway agency for use on Federal-aid projects, except exempt, non-NHS projects, (a) they must be supplied through competitive bidding with equally suitable unpatented items; (b) the highway agency must certify that they are essential for synchronization with the existing highway facilities or that no equally suitable alternative exists; or (c) they must be used for research or for a distinctive type of construction on relatively short sections of road for experimental purposes. Our regulations concerning proprietary products are contained in Title 23, Code of Federal Regulations, Section 635.411.
- This acceptance letter shall not be construed as authorization or consent by the FHWA to use, manufacture, or sell any patented device for which the applicant is not the patent holder. The acceptance letter is limited to the crashworthiness characteristics of the candidate device, and the FHWA is neither prepared nor required to become involved in issues concerning patent law. Patent issues, if any, are to be resolved by the applicant.
Sincerely yours, /* Signature of Michael S. Griffith */
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