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U.S. Department of Transportation

Federal Highway Administration

400 Seventh St., S.W.
Washington, D.C. 20590


May 17, 2005

Refer to: HSA-10/WZ-198

Ronald K. Faller, PhD, PE
Midwest Roadside Safety Facility
University of Nebraska - Lincoln
P.O. Box 880529
Lincoln, Nebraska 68588-0529

Dear Dr. Faller:

Thank you for your letter of November 12, 2004, requesting the Federal Highway Administration (FHWA) acceptance of the Three D Traffic Works unballasted plastic barricade system as a crashworthy traffic control device for use in work zones on the National Highway System (NHS). Accompanying your letter was a report of the crash testing you conducted and video of the tests. 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."


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.

TD2150 Blow Molded Plastic Barricade

The barricade has an overall height when folded of 46.0 inches. It is 24.5 inches wide and 2.25 inches thick. When deployed the top of the upper panel is 36.375 inches above the pavement. Two 0.375 inch diameter x 5.5 inch long Grade 5 zinc coated hex head bolts with two 1 inch diameter washers and a lock nut were used to connect the barricade hinges together. One Empco-Lite Model 100 warning light was attached to the top of each barricade through a monolithically-molded plastic bracket. The 6V lantern battery light was attached to the top of the barricade with a 1/2 inch diameter x 3 1/4 inch long heavy cap screw fastener with a 1 1/8 inch diameter flat washer under the head. The unballasted barricade weighs 14.82 pounds, and the warning light with battery weighs 3.14 pounds for a total weight of 17.96 pounds. The warning lights used in System #1 were Empco-Lite Model 100, and in System #2 were Starlite 747.


Bogie vehicle testing was conducted on the Three D Traffic Works devices. Two stand-alone examples of the device were tested in tandem, one head-on and the next placed six meters downstream turned at 90 degrees, as called for in our guidance memoranda.

The tests are summarized in the table below.

Test Number


Barricade Tested


Weight of Tested Barricade

8.15 kg (18.0 lbs)

Flags? Lights?

Empco Lite Model 100

Mass of Test Vehicle

1119 kg (2467 lbs)

Impact Speed

100.5 km/hr (62.4 mph)

Velocity Change Head-on

2.4 km/h (1.5 mph)

Velocity Change End-on

1.5 lm/h (0.9 mph)

Extent of contact

Impact to bumper, grille, hood

Windshield Damage

No contact with windshield

This crash-testing program used a hard-nosed bogie vehicle of a mass larger than the standard 820C test vehicle. There are significant constraints involved in using such a non-standard testing device, some of which are:

  1. The potential vehicle velocity change must be considered insignificant.
  2. The crush characteristics of an automobile bumper must not be expected to have a significant affect on the trajectory of the test article.
  3. The profile of the bogie vehicle must be configured to replicate the outline of a production vehicle. The MwRSF bogie was configured to replicate the outline of a Geo Metro, a vehicle commonly used in testing of work zone devices.
  4. No part of the test article may intrude into the windshield area of the vehicle after impact.

In this test both barricades impacted the bumper, grille, and / or hood area of the bogie and were projected up and ahead of the bogie. No part of either barricade struck the "windshield" area of the bogie.


The results of the testing met the FHWA requirements and, therefore, the device described 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:

Sincerely yours,

/original signed by/
John R. Baxter, P.E.
Director, Office of Safety Design
Office of Safety

3 Enclosures

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