November 19, 2002

Refer to: HSA-10/WZ-118

Mr. R. Scott Behm
National Sales Manager
Three D Traffic Works, Inc.
430 North Varney Street
Burbank, California  91502

Dear Mr. Behm:                                                           

Thank you for your letter of March 11, 2002, requesting Federal Highway Administration (FHWA) acceptance of your company's channelizing devices ascrashworthy traffic control devices for use in work zones on the National Highway System (NHS).  Accompanying your letter was product literature for these items.  You requested that we find the TD6000 VIP Vertical Indicator Panel and the TD6000 Ringtop Delineator Post and Ringtop Stackable Cone 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."  You also requested a modification to your company's

Type III barricade design that was originally found acceptable in our letter WZ-82 of September 14, 2001.  Action on the barricade was handled in Acceptance Letter WZ-128 dated July 12, 2002.


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 were those lightweight devices which could be self-certified by the vendor, Category II devices were other lightweight devices which needed individual crash testing, Category III devices were barriers and other fixed or massive devices also needing crash testing, and Category IV devices were trailer mounted lighted signs, arrow panels, etc.  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.  A brief description of the devices follows:

The TD6000 VIP Vertical Indicator Panel is a Category 2 work zone traffic control device.  It is molded of Low Density Polyethylene and is available in two heights, 45 inches and 52 inches.

The weight of the 45 inch VIP is 5.5 pounds.  Either may be ballasted with recycled rubber bases weighing 10, 20, or 30 pounds.  The highest of these bases has a profile of 3.5 inches above the pavement.

The Rigtop Delineator Post and Ringtop Stackable Cone are Category 1 work zone traffic control devices and thus require no additional action by the FHWA for them to be acceptable for use on the NHS. Category 1 devices must be self-certified by the manufacturer that they meet crashworthiness requirements. More information on the self-certification of Category 1 devices may be found in our memorandum of  August 28, 1998. This memorandum may be seen from our web site: You may also find our Question and Answer page to be of help at:

If these devices are to be used with a warning light, flags or sign on top then they need to be crash tested.


The VIP Vertical Indicator Panel with rubber base is similar to a number of other vertical panel and cone devices.  We concur in your contention that it may be considered crashworthy with no additional testing and, therefore, the devices described above and shown in the enclosed drawings for reference are acceptable for use on the NHS under the range of conditions similar models were tested, when proposed by a State.

Please note the following standard provisions that apply to FHWA letters of acceptance:

Sincerely yours,

Carol H. Jacoby, P.E.
Director, Office of Safety Design