March 27, 2003

Refer to: HSA-10/WZ-135

Mr. Marc Christensen
Off the Wall Products, LLC
P.O. Box 1461
Salt Lake City, UT  84110-14461

Dear Mr. Christensen:

Thank you for your letters of June 14, August 16, and December 17, 2002, requesting Federal Highway Administration (FHWA) acceptance of your company's water-filled longitudinal channelizers as crashworthy traffic control devices for use in work zones on the National Highway System (NHS).  Accompanying your letter was a report of crash testing conducted by E-Tech Testing Services, summaries of additional tests, drawings of the individual units, and videos 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.” On March 12, 2003, you provided a complete final report covering the crash testing of the device as a longitudinal channelizer.

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:

The Multi-Barrier is a rotation molded hollow plastic barricade section, which can accept water ballast.  Each high-impact, UV-resistant polyethylene section is 1219 mm (48 inches) tall and 1016 mm (40 inches) long.  Each section is 598 mm (23.5 inches) wide at the base, tapering on one side to a top width of 152 mm (6 inches).  The wall thickness is 5.1 mm (0.20) inches, and one section weighs 22.7 kg (50 pounds) empty. The specifications and drawings are given in the enclosed literature for reference.

Individual units were crash tested as Type II barricades, and found acceptable in FHWA Acceptance Letter WZ-8 date February 5, 1999.  This action, WZ-135, is to qualify the same units linked longitudinally and filled with water, deployed as a Test Level-1 (TL-1) longitudinal channelizer.

Testing

Full-scale automobile testing was conducted on your company's devices.  The crash test matrix was a modification of both the NCHRP Report 350 tests for longitudinal barriers and work zone traffic control devices.  The crash tests are summarized in the table below:

Findings

As expected the vehicle penetrated the installation.  The occupant impact velocity of the small car exceeded that for a work zone traffic control device, but the occupant impact velocities and accelerations in both tests were within those specified for a barrier.

The results of the testing met the unique requirements established for water-filled longitudinal channelizers and, therefore, the device described above and shown in the enclosed drawings for reference are acceptable for use on the NHS under the range of conditions tested (Report 350 TL-1), when proposed by a State or other highway agency.

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, 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 FHWA and NCHRP Report 350.
  
  
• To prevent misunderstanding by others, this letter of acceptance, designated as number WZ-135 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 Multi-Barrier is a patented device and is 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.
  
  
• This acceptance letter shall not be construed as authorization or consent by the Federal Highway Administration to use, manufacture, or sell any patented device. Patent issues are to be resolved by the applicant and the patent owner.

Sincerely yours,

Michael S. Griffith
Acting Director, Office of Safety Design
Office of Safety

Enclosures