Refer to: HSA-10/LS-53
Mr. Robert A. Sik
2728 Wingate Avenue
Akron, Ohio 44314
Dear Mr. Sik:
Thank you for your letter of May 1, 2002, requesting Federal Highway Administration (FHWA) acceptance of a modification to your company's TS-1000 Threaded Traffic Signal Pedestal Base and TS-1000 Modified Threaded Traffic Signal Pedestal Base as breakaway bases for use on the National Highway System (NHS). Accompanying your letter were drawings of the original and modified bases. You requested that we find the modifications to these bases 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.”
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.
Full-scale automobile testing was conducted on the TS-1000 bases, and they were accepted in our November 19, 1997, letter LS-47. The proposed change to the bases involves adding a collar to the top to provide a more secure anchorage for the pole that is threaded into the top of the base. Because these bases' crash performance is by virtue of their breaking at the bottom, the addition of the collar and/or gussets at the top should have no adverse affect on their breakaway performance.
Because the performance of the subject bases modified with the collar (designated TS-1000-L) and/or gussets (designated TS-1000-L With Gussets) is expected to be similar to the crash tested bases, 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
The Akron Foundry bases are or will be patented products and are 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 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.
Carol H. Jacoby, P.E.
Director, Office of Safety Design