January 24, 2003

Refer to: HSA-10/WZ-139

Mr. Michael Denman
The Roadmarker Company
835 Terry Francois Boulevard
San Francisco, California 94107

Dear Mr. Denman:

This is in response to your letter of November 21, 2002, requesting Federal Highway Administration (FHWA) acceptance of your company's Multipurpose Barricades as crashworthy traffic control devices for use in work zones on the National Highway System (NHS).  Accompanying your letter were reports of crash testing conducted by E-Tech Testing Services, Ind., and video of the tests.  You requested that we find these devices 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.”  

Introduction                           

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:

Individual barricades are made up of two blow-molded polyethylene plastic panels hinged at the top such that the assembly assumes an A-frame open stance of 1067 mm and a vertical drop from the top stripe bar of 914 mm.  A 610 mm wide barricade was selected for testing.  A unique feature of the barricade is that its top cross member has a slot that will accept a plastic rail which can, in turn, be connected to succeeding barricades.  Rails are made of extruded vinyl measuring 25mm x 203 mm and are available in a variety of standard lengths.

Because of the unique interconnecting feature of the Multipurpose barricade, many possible barricade combinations and configurations could be selected for crash testing.  Testing of all combinations would not be practical or cost effective.  Therefore, a configuration representing a “worst case” in terms of potential warning light detachment and interaction with the windshield was selected for testing.

The selected test configuration consisted of three interconnected barricades for the “normal” impact orientation and two interconnected barricades for the “perpendicular” impact orientation. Standard 1829 mm long rails were used to connect the normal impact barricades and a standard 2438 mm long rail was used between perpendicular impact barricades.  The leading barricades in the normal and perpendicular orientations were each equipped with a warning light.

Testing                                   

Full-scale automobile testing was conducted on your company' devices.  Two stand-alone examples of the devices 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.

Findings                                 

Damage was limited to minor cosmetic damage and cracking to the windshield.  There were no holes, no deformation, and virtually no glass fragments inside the passenger compartment.  The results of the testing met the FHWA requirements and, therefore, the devices described in the various requests 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, or 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 FHWA and NCHRP Report 350.
• ·        To prevent misunderstanding by others, this letter of acceptance, designated as number WZ-139 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.
• ·        Roadmarker Multipurpose Barricades may include patented components and if so are 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 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 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.

Sincerely yours,

Harry W. Taylor,
Acting Director, Office of Safety Design

Enclosure