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U.S. Department of Transportation

Federal Highway Administration

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

May 3, 2006

Refer to: HSA-10/WZ-236

Mr. Jeff Johnson, President
Trafficade Service, Inc.
2533 W. Holly Street
Phoenix, Arizona 85009

Dear Mr. Johnson :

Thank you for your letter of February 7, 2006, requesting the Federal Highway Administration (FHWA) acceptance of your company's HD-3612 Sign Stand as a crashworthy traffic control device 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 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."

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. Our new acceptance process was outlined in our memorandum "FHWA Hardware Acceptance Procedures – Category 2 Work Zone Devices" dated November 11, 2005.

A brief description of the devices follows:

The HD-3612 Sign Stand is a portable sign system featuring a 1.5-inch x 1.5-inch x 1/8-inch thick forged steel angle iron upright support. The upright is supported in a 2-inch square tube socket, which is in turn welded to a 20-inch square, ¼-inch thick steel base plate. The upright, socket and base plate are A-36 steel. The upright is attached to the socket with a ½ inch diameter by 3-inch long SAE J429 Grade 8 hex fastener and nut.

The stand features a 36-inch diamond shaped sign made of 0.080-inch thick solid 5052-H2 aluminum sheet. The sign is bolted to the upright with two 3/8-inch diameter by 1-inch long ASTM A307 hex fasteners with 1 ¼-inch OD fender washers and nylon insert lock nuts. When deployed the bottom of the sign is a nominal 12 inches above ground level.

The top of the upright is fitted with a flag bracket attached with a 3/8-inch diameter by 1-inch long ASTM A307 hex fastener and nylon insert lock nut. The bracket held two flags that were slipped into the 1-inch schedule 40 pipe sockets. The flags were 16-inch square vinyl fabric attached to 11/16-inch diameter by 24-inch long wood dowels. The top most portion of the upright has a hole for attaching a warning light. A 3.0-pound C&C Signals Type A LED warning light was included in the testing. The test article mass was 56 pounds.

Full-scale automobile testing was conducted on your company's 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.

NCHRP Report 350 Test 3-71

Test Number


Sign Stand Tested

Head On


Mounting heights

12 inches to the bottom, 73 inches to top of light

Flags? Lights?

2 flags, 1 light

Mass of Test Vehicle

1841 pounds (837 kg)

Impact Speed

64.6 mph (103.9 kmh)

60.3 mph (97.0 kmh)

Velocity Change

1.9 m/s

1.9 m/s

Extent of contact

Sign struck hood, flag hit windshield

Sign struck hood

Windshield Damage

Area of moderate cracking

None from this impact

Other notes

Light remained attached

Light remained attached


Damage was limited to significant deformation to the hood, minor damage to the bumper and grille, and one area of concentrated cracking along with significant overall damage to the windshield, but no penetration.

The results of the testing met the FHWA requirements and, therefore, the devices described in the 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.

You also requested acceptance for use of this stand with smaller or lighter substrate signs. The E-TECH test report supports this request. Therefore, the Trafficade HD-3612 Sign Stand is also acceptable when used with substrates that are smaller or lighter than the 36-inch diamond, 0.080 5052-H32 Aluminum substrate used in the test articles.

The incoming FHWA Form is also enclosed for reference.

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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