Refer to: HSA-10/LS-52

Armand A. Damiano, P.E. 

Product Engineering Manager 

Valmont Industries, Inc. 

P.O. Box 358 

Valley, Nebraska 68064 

Dear Mr. Damiano: 

 

Thank you for your March 1 letter to Mr. Nicholas Artimovich of my office requesting Federal 

Highway Administration (FHWA) acceptance of your company’s breakaway coupling for use 

with luminaire supports on the National Highway System (NHS). Accompanying your letter was 

a report from E-Tech Testing Services and videos of the crash tests. You requested that we find 

Valmont’s Pro-Tech couplings 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.” Your email of May 29 provided 

additional information in response to our request. 

Introduction 

Testing of the supports was in compliance with the guidelines contained in the NCHRP Report 

350, Recommended Procedures for the Safety Performance Evaluation of Highway Features. 

Requirements for breakaway supports are those in the American Association of State Highway 

and Transportation Officials' Standard Specifications for Structural Supports for Highway Signs, 

Luminaires and Traffic Signals. 

Testing 

Pendulum testing was conducted on a steel light pole with four Pro-Tech couplings positioned to 

support a 254.0 mm base diameter. The height of the tapered pole was 15 240 mm, and its wall 

thickness was 3.04 mm. The mass of the test article was 320 kg, and the mass of the pendulum 

bogie was 845 kg. The couplings were fastened to a rigid steel foundation with 25.4 mm 

diameter SAE J429 GD 8 galvanized studs. The couplings were torqued to the manufacturer’s 

specifications. The support pole base was positioned and fastened to the top of the couplings 

with additional 25.4 mm bolts. The heavy hex nuts were torqued according to the 

manufacturer’s specifications. The devices as tested are shown in the enclosures. 
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Test # NCHRP 350 Speed Article Occup. Speed Delta V 

1 3-60 34.9 km/h Valmont Pro-Tech no contact 3.30 m/s 

2 Extrapolation (100 km/h) n/a 4.76 m/s

Occup. Speed: Occupant Impact Speed: Speed at which a theoretical front seat occupant will 

contact the windshield. In meters per second 

Delta V: Speed change of the test vehicle. In meters per second. 

Findings 

Velocity changes were all within acceptable limits, and the maximum stub height was 26 mm. 

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

and shown in the enclosed drawings for reference are acceptable for use as Test Level 3 devices 

on the NHS under the range of conditions tested, when proposed by a State. 

Please note the following standard provisions, which 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 LS-52 shall not be reproduced except in full. As this letter and the 

supporting documentation, which support it, become public information, it will be 

available for inspection at our office by interested parties.

The Valmont Pro-Tech coupling is or will be a patented product and is considered 

"proprietary." The use of proprietary devices specified on Federal-aid projects, except 

exempt, non-NHS projects: (a) must be supplied through competitive bidding with 

equally suitable unpatented items; (b) the highway agency must certify that they are 
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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, 

Carol H. Jacoby, P.E. 

 Director, Office of Safety Design 

Enclosure