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U.S. Department of Transportation

Federal Highway Administration

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


September 9, 2005

Refer to: HSA-10/WZ-214

Mr. Marc Christensen
Managing Member
Off the Wall Products, LLC
P.O. Box 1461
Salt Lake City, Utah 84110

Dear Mr. Christensen:

Thank you for your letter of May 2, 2005, requesting the Federal Highway Administration (FHWA) acceptance of the Off-the-Wall MB-42 x 45 Longitudinal Channelizing Barricade (LCB) as a crashworthy traffic control device for use in work zones on the National Highway System (NHS). Accompanying your letter was the report of crash testing conducted by the Transportation Research Center, Inc., and video of the tests. You requested that we find this LCB 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." You provided additional information in response to our request on August 4, 2005.


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.

A brief description of the devices follows:

The Multi-Barrier Model MB-42 x 45 LCB system consists of multiple interconnected polyethylene units that may be ballasted with water. Each unit is blow molded of HLMI/ HDPE (high molecular weight high density polyethylene) and weighs 35 pounds empty. For this test, a line of 27 units were linked, each unit ballasted with approximately 8 gallons of water.


Full-scale automobile testing was conducted on your company's device. As the LCB are not covered in the NCHRP Report 350 the FHWA has established that the NCHRP Test 3-10 be used with all evaluation criteria being required with the exception that controlled penetration of the test article is acceptable. Twenty-seven units were linked and placed at an angle of 20 degrees with respect to the line of travel of the test vehicle. The vehicle impacted the LCB at the joint between barricades number 13 and 14. The test vehicle penetrated the line of interconnected LCB units, displacing units 13 through 20. The vehicle remained stable, coming to rest approximately 210 feet downstream from the point of impact and approximately 10 feet behind the LCB.

Units 12-15 had warning lights, retro reflective striping, 6 x 8 inch delineator panels, and an impact plate attached to the front face (impact side) of the LCB. This 1/8 inch thick HDPE impact plate permits the units to carry retroreflective striping, and is not expected to have a significant effect on the crashworthiness of the LCB.

The test is summarized in the table below.

Test Number

NCHRP Report 350 Test 3-10

TRC Test No. 050408

Device Tested

Off-the-Wall MB-42 x 45


Weight of Empty Units

35 pounds

Water Ballast?

8 gallons/66 pounds

Flags? Lights?

Warning lights, Impact Plates,

  and Delineator Panels on units #12, 13, 14, 15

Mass of Test Vehicle

836.7 kg

Impact Speed

99.8 km/hr

Velocity Change

4.9 m/sec

Extent of contact

Bumper, hood, and left front side

Windshield Damage

No contact

Other notes

No measurable crush to the vehicle exterior


Damage was limited to cosmetic scrapes to the front and left side of the test vehicle. There was no significant impact from exposed units once the vehicle had penetrated the line of the LCB. The warning lights remained attached to the barricades.

The results of the testing met the FHWA requirements and, therefore, the device described in above and detailed in the enclosed drawings is acceptable for use as a LCB on the NHS under the range of conditions tested, when proposed by a State. The Off the-Wall MB-42 x 45 HMLI/HDPE LCB is acceptable with or without warning lights, impact plates, delineator panels and with up to approximately 8 gallons of water in each unit.

As the quantity of water used for ballast may substantially affect the performance of longitudinal channelizing barricades, a permanent indication shall be applied to each unit notifying users of this limitation.

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

Sincerely yours,

/original signed by George Ed Rice, Jr./

John R. Baxter, P.E.
Director, Office of Safety Design
Office of Safety


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