Safety Eligibility Letter WZ - 193
U.S. Department of Transportation
Federal Highway Administration
400 Seventh St., S.W.
Washington, D.C. 20590
December 6, 2005
In Reply Refer To: HSA/ WZ-193 Amendment #1
Mr. Peter Speer
Davidson Traffic Control Products
Filtrona Extrusion, Inc.
3110 70th Avenue East
Tacoma, Washington 98424
Dear Mr. Speer:
Thank you for your email of September 23, 2005, requesting the Federal Highway Administration (FHWA) acceptance of a modification to your company's FG300 Curb System as a crashworthy traffic control device for use in work zones on the National Highway System (NHS). The original FG300 Curb System was made of two basic parts, the curb unit, and a "base" unit that supported a road tube. Your proposal is to combine the two parts into one, which would simplify installation. You requested that we find the modified 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."
The principal reason for conducting crash testing of curb channelizer units is to ensure that the linked units do not separate upon impact. By combining the two primary units into one you reduce the likelihood that parts will separate. We concur that this would improve the safety performance of the FG300 curb system. We understand that the number of anchors will be reduced because you no longer have two components that need to be anchored separately.
The devices described in the original acceptance letter, WZ-193, dated November 2, 2004, as modified above and detailed in the enclosed drawings are acceptable for use on the NHS under the range of conditions tested, when proposed by a State.
Please note the following standard provisions that apply to FHWA letters of acceptance:
- Our 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, it reserves the right to modify or revoke its 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 they will meet the crashworthiness requirements of the FHWA and the NCHRP Report 350.
- To prevent misunderstanding by others, this letter of acceptance, designated as number WZ-193 in conjunction with WZ-193 Amendment #1 shall not be reproduced except in full. This letter, and the test documentation upon which this letter is based, is public information. All such letters and documentation may be reviewed at our office upon request.
- The Davidson Plastics FG300 Curb System is a patented device and is considered "proprietary." The use of proprietary work zone traffic control devices in Federal-aid projects is generally of a temporary nature. They are selected by the contractor for use as needed and removed upon completion of the project. Under such conditions they can be presumed to meet requirement "a" given below for the use of proprietary products on Federal-aid projects. On the other hand, if proprietary devices are specified by a highway agency for use on Federal-aid projects they: (a) must be supplied through competitive bidding with equally suitable unpatented items; (b) the highway agency must certify that they are essential for synchronization with 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, a copy of which is enclosed.
- 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.
/original signed by/
John R. Baxter, P.E.
Director, Office of Safety Design
Office of Safety