November 15, 2001 

 Refer to: HSA-10/B91 

Mr. William H. McClintic 

President 

Aeolian Enterprises, Inc. 

PO Box 888 

Latrobe, Pennsylvania 15650 

Dear Mr. McClintic: 

In your October 17 letter, you requested the Federal Highway Administration’s 

acceptance of a recycled plastic block, called the Aeolian blockout, for use with 

strong steel-post w-beam guardrail on the National Highway System (NHS). To 

support this request, you also sent me copies of a test report prepared by the Texas 

Transportation Institute (TTI) and videotapes of the pendulum tests that were 

conducted by TTI. 

The Aeolian blocks are molded from a composition of 97.5 per cent recycled high 

density polyethylene (HDPE), 0.5 per cent blowing agent, and 2.0 per cent carbon 

black concentrate. Each block is nominally 150 mm by 200 mm by 360-mm tall, 

with a 114-mm wide, 10-mm deep routing on the field side to fit over the steel post 

flange. Testing consisted of two separate tests in each of which the pendulum struck 

your block mounted between a W150 x 13.5 (W6 x 9) post and a short section of wbeam guardrail. The base plate welded to the steel post was bolted to a rigid steel 

reaction plate. In both tests, the posts failed just above the welds at the base plate 

and the blocks remained intact. 

Based on the results of the pendulum tests run, your product may be considered 

acceptable for use on the National Highway System (NHS) when it conforms to the 

dimensions noted above and is composed of the same materials as the tested blocks. 

As with all other recycled material blocks accepted for use on the NHS, this FHWA 

acceptance is based solely on the reported impact performance in the pendulum test 

and is not intended to address the long-term performance or durability of the 

product. Since your block is a proprietary product, its use on Federal-aid projects, 

except exempt, non-NHS projects, is subject to the conditions listed in Title 23, Code 

of Federal Regulations, Section 635.411, a copy of which is enclosed for your ready 

reference. If you have any questions, please call Mr. Powers at (202) 366-1320. 

 

Sincerely yours, 

 (original signed by Frederick G. Wright, Jr.) 

 Frederick G. Wright, Jr. 

 Program Manager, Safety 

 Enclosure 
Sec. 635.411 Material or product selection. 

(a) Federal funds shall not participate, directly or indirectly, in payment for any 

premium or royalty on any patented or proprietary material, specification, or 

process specifically set forth in the plans and specifications for a project, unless: 

(1) Such patented or proprietary item is purchased or obtained through competitive 

bidding with equally suitable unpatented items; or 

(2) The State highway agency certifies either that such patented or proprietary item 

is essential for synchronization with existing highway facilities, or that no equally 

suitable alternate exists; or 

(3) Such patented or proprietary item is used for research or for a distinctive type of 

construction on relatively short sections of road for experimental purposes. 

(b) When there is available for purchase more than one nonpatented, 

nonproprietary material, semifinished or finished article or product that will fulfill 

the requirements for an item of work of a project and these available materials or 

products are judged to be of satisfactory quality and equally acceptable on the basis 

of engineering analysis and the anticipated prices for the related item(s) of work are 

estimated to be approximately the same, the PS&E for the project shall either 

contain or include by reference the specifications for each such material or product 

that is considered acceptable for incorporation in the work. If the State highway 

agency wishes to substitute some other acceptable material or product for the 

material or product designated by the successful bidder or bid as the lowest 

alternate, and such substitution results in an increase in costs, there will not be 

Federal-aid participation in any increase in costs. 

(c) A State highway agency may require a specific material or product when there 

are other acceptable materials and products, when such specific choice is approved 

by the Division Administrator as being in the public interest. When the Division 

Administrator's approval is not obtained, the item will be nonparticipating unless 

bidding procedures are used that establish the unit price of each acceptable 

alternative. In this case Federal-aid participation will be based on the lowest price so 

established. 

(d) Appendix A sets forth the FHWA requirements regarding (1) the specification of 

alternative types of culvert pipes, and (2) the number and types of such alternatives 

which must be set forth in the specifications for various types of drainage 

installations. 

(e) Reference in specifications and on plans to single trade name materials will not 

be approved on Federal-aid contracts.