Federal Highway Administration
400 Seventh St., S.W.
Washington, D.C. 20590
September 7, 2005
Refer to: HSA-10/WZ-217
Mr. Scott Behm
National Sales Manager
Three D Traffic Works
430 North Varney Street
Burbank, California 91502
Dear Mr. Behm:
Thank you for your letter of June 3, 2005, requesting the Federal Highway Administration (FHWA) acceptance of modifications to your company's TD2400 All Plastic Type III Works Barricades as crashworthy traffic control devices for use in work zones on the National Highway System (NHS). You requested that we find these devices 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" based on crash testing of similar hardware made by your company and/or by others.
The FHWA guidance on crash testing of work zone traffic control devices is contained in two memoranda. The first, dated July 25, 1997, titled "INFORMATION: Identifying Acceptable Highway Safety Features," established four categories of work zone devices: Category I devices are those lightweight devices which are to be self-certified by the vendor, Category II devices are other lightweight devices which need individual crash testing but with reduced instrumentation, Category III devices are barriers and other fixed or heavy devices also needing crash testing with normal instrumentation, and Category IV devices are trailer mounted lighted signs, arrow panels, etc. for which crash testing requirements have not yet been established. The second guidance memorandum was issued on August 28, 1998, and is titled "INFORMATION: Crash Tested Work Zone Traffic Control Devices." This later memorandum lists devices that are acceptable under Categories I, II, and III.
The TD2400 All Plastic Type III Works Barricades was originally accepted in WZ-132 and was described as:
The Three D Traffic Works TD2400 Series Type III Barricade is an FHWA Category II work zone traffic control device. It is an all plastic, lightweight, portable barricade made from a specially formulated polypropylene plastic with UV stabilizers and cold weather package.
Panels for crashworthy barricades are available in 1219, 1524, 1829, and 2438 mm (4, 5, 6, and 8 foot) lengths. A 2438 mm (8 foot) wide barricade panel was selected for testing. The barricade plastic upright support legs are referred to as Tuff-1TM uprights and are specially designed with an extrusion pattern which yields additional strength. These plastic uprights area nominal 1600 mm (5 feet, 4 inches) in length and 44.5 mm (1.75 inches) square. The uprights are supported by injection molded "EZ Foot" bases with nominal 1524 mm (5 feet) length and 305 mm (1 foot) nominal height and width.
You requested the following modifications to the crash-tested barricade design:
As these materials have been used successfully in crash tests of other barricade designs, and because some are incorporated into the "generic Type III barricade" detailed in the FHWA acceptance letter WZ-85 dated November 15, 2001, we find them acceptable for use on the NHS under the range of conditions originally tested, when proposed by a State.
You had also asked for acceptance of a 12 foot wide barricade. This request is denied, as the materials used in the crash-tested barricades are proprietary to the companies who sponsored the crash testing.
Please note the following standard provisions that apply to the FHWA letters of acceptance:
/original signed by George E. Rice, Jr./
John R. Baxter, P.E.
Director, Office of Safety Design
Office of Safety
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