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FHWA Home / Safety / Roadway Departure / Safety Eligibility Letter

Safety Eligibility Letter B-136a

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1200 New Jersey Ave. S.E.
Washington, D.C. 20590

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U.S. Department of Transportation
Federal Highway Administration

February 2, 2017

Reply Refer To:

Nathan Binette
Evonik Cyro LLC
1796 Main Street
Sanford, Maine 04073

Dear Mr. Binette:

This letter is in response to your December 22, 2015, request for the Federal Highway Administration (FHWA) to review a roadside safety device, hardware, or system for eligibility for reimbursement under the Federal-aid highway program. This FHWA letter of eligibility is assigned FHWA control number B-136A and is valid until a subsequent letter is issued by FHWA that expressly references this device.


The following devices are eligible, with details provided in the form which is attached as an integral part of this letter:

Scope of this Letter

To be found eligible for Federal-aid funding, modified roadside safety devices should meet the crash test and evaluation criteria contained in the National Cooperative Highway Research Program (NCHRP) Report 350. However, the FHWA, the Department of Transportation, and the United States Government do not regulate the manufacture of roadside safety devices. Eligibility for reimbursement under the Federal-aid highway program does not establish approval, certification or endorsement of the device for any particular purpose or use. 

This letter is not a determination by the FHWA, the Department of Transportation, or the United States Government that a vehicle crash involving the device will result in any particular outcome, nor is it a guarantee of the in-service performance of this device. Proper manufacturing, installation, and maintenance are required in order for this device to function as tested.

This finding of eligibility is limited to the crashworthiness of the system and does not cover other structural features, nor conformity with the Manual on Uniform Traffic Control Devices.

Eligibility for Reimbursement

FHWA previously issued an eligibility letter for the roadside safety system described in your pending request. Your pending request now identifies a modification to that roadside safety system.

The original roadside safety device information is provided here:

Name of system: Paraglas Soundstop Noise Wall TL-4
Type of system: Noise Wall atop concrete barrier
Date of original Request: April 12, 2005
Original eligibility letter date: May 18, 2005
FHWA Control number: B-136
Date of current request: December 22, 2015
Complete submission received: December 2, 2016

The modification(s) consists of the following changes:

1) Connection details of horizontal rails to posts.
2) Replacement of four 3/4" diameter anchors with four 7/8" diameter anchors.
3) Modification of noise barrier panel inserts to reduce snag potential of vehicle components.
4) Replacement of fabricated splice sleeves with commonly available tube sections.
5) Clarification of allowable horizontal rail positions for concrete bridge rails of varying depths.
6) Clarification of allowable expansion joint details and associated splice connections.
7) Clarification of lowest horizontal rail position for parapets of different heights.
8) Clarification of allowable heights of the system and associated top horizontal rail position.
9) Alternate anchorage details to address variability in parapet shapes.

FHWA concurs with the recommendation of the accredited crash testing laboratory as stated within the attached form. We also note the change in the name of the "Paraglas" material to "Acrylite" with no change in the product design or characteristics.

Full Description of the Eligible Device

The device and supporting documentation, including reports of the crash tests or other testing done, videos of any crash testing, and/or drawings of the device, are described in the attached form.


If a manufacturer makes any modification to any of their roadside safety hardware that has an existing eligibility letter from FHWA, the manufacturer must notify FHWA of such modification with a request for continued eligibility for reimbursement. The notice of all modifications to a device must be accompanied by:

FHWA's determination of continued eligibility for the modified hardware will be based on whether the modified hardware will continue to meet the relevant crash test criteria.

You are expected to supply potential users with sufficient information on design, installation and maintenance requirements to ensure proper performance.

You are expected to certify to potential users that the hardware furnished has the same chemistry, mechanical properties, and geometry as that submitted for review, and that it will meet the test and evaluation criteria of the NCHRP Report 350.

Issuance of this letter does not convey property rights of any sort or any exclusive privilege. This letter is based on the premise that information and reports submitted by you are accurate and correct. We reserve the right to modify or revoke this letter if: (1) there are any inaccuracies in the information submitted in support of your request for this letter, (2) the qualification testing was flawed, (3) in-service performance or other information reveals safety problems, (4) the system is significantly different from the version that was crash tested, or (5) any other information indicates that the letter was issued in error or otherwise does not reflect full and complete information about the crashworthiness of the system.

Standard Provisions


Sincerely yours,

/* Signature of Scott T. Johnson */

Scott T. Johnson
Acting Director, Office of Safety Technologies
Office of Safety


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