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April 13, 2007

In Reply Refer To:



Mr. Peter Speer

Davidson Traffic Control Products

Filtrona Extrusion, Inc.

3110 70th Avenue East

Tacoma, WA 98424

Dear Mr. Speer:

Thank you for your letter of October 12, 2006, requesting the Federal Highway Administration (FHWA) acceptance of your company's modified X-tube mounted to a 40 pound portable rubber base as a crashworthy traffic control device for use on the National Highway System (NHS). Accompanying your letter was background information regarding informal tests conducted. You requested that we find this device 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."

A drawing of the proposed modified X-tube mounted to a 40 pound portable rubber base is enclosed. The complete assembly is comprised of the following components:






12 x 44 sign

0.125 inch UHMW

12 x 44 x 0.125 thick

2.7 lbs

1 -2 each

Modified X-tube

Co-polymide TPE

3 x 2 x 48 tall x 0.15 thick

1.9 lbs

1 each

Yeti Rubber Base

Recycled rubber/steel

17.5 x 27 x 3.8 thick

40 lbs

1 each

Based on our records of successfully crash tested vertical panels, equivalent designs such as yours are inherently safe. Therefore, lightweight vertical panels with no lights attached, mounted to a flexible or a low-profile weighted base, and with a top panel height measuring no more than 48 inches, are now accepted by the FHWA as a Category 1 device and may be self-certified by the vendor. Your vertical panel measures 52 inches tall. Although the height is 4 inches taller than many previously tested designs, it is not a significant difference. As a reminder, crash testing is still needed to determine the FHWA acceptance of vertical panels with lights attached.

Please note the following standard provisions that apply to the 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, 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-232, 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 device is a patented product and considered proprietary. If proprietary devices are specified by a highway agency for use on Federal-aid projects, except exempt, non-NHS 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 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,

John R. Baxter, P.E.

John R. Baxter, P.E.

Director, Office of Safety Design

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