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                Safety Eligibility Letter SS-174
  
  **Hardware Type:**
            Sign Supports, Mailboxes, and Delineator Posts
                          **Code:**
            SS-174
                          **Date:**
            11/23/2011
                          **Testing Criteria:**
            NCHRP 350
                          **Manufacturer:**
            Trinity Highway Products
                          **Device Description:**
            Breakaway Sign Support Systems of Northwest Pipe Company
                          **View PDF:**
            ss174.pdf (344.64 KB)
    
    Safety Eligibility Letter SS-174 - Safety

			

						
**Download Version**PDF [344 KB]

DOT logoU.S. Department of Transportation**Federal Highway Administration**

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

November 23, 2011
In Reply Refer To:
 HSST/SS-174T.J. Aslin
  Trinity Highway Products, LLC
  2525 Stemmons Freeway
  Dallas, Texas 75207
Dear Mr. Aslin:
This letter is in response to your request for the Federal Highway Administration (FHWA) determination of eligibility for reimbursement under the Federal-aid highway program for highway safety products formerly manufactured by Northwest Pipe Company.
Name of system:

 	 Breakaway Sign Support Systems of Northwest Pipe CompanyType of system:

 	 Breakaway Sign SupportsTest Level:

 	 NCHRP Report 350 Test Level 3Testing conducted by:
 	 
 	 NCHRP Report 350 Test Level 3Date of request:
 	  October 10, 2011Date initially acknowledged:
 	  November 3, 2011You certify that the devices described herein meet the crashworthiness criteria of the National Cooperative Highway Research Program (NCHRP) Report 350. Based on the testing previously conducted you asked that we find the device(s) eligible for reimbursement under the Federal-aid highway program.  Eligibility for reimbursement under the Federal-aid highway program does not establish approval or endorsement by the FHWA for any particular purpose or use.
**Decision:**
 The following devices are eligible, with details provided in the referenced letters:
All breakaway devices previously accepted for Northwest Pipe Company.**Requirements**
 Roadside safety devices should meet the guidelines contained in the NCHRP Report 350 or the American Association of State Highway and Transportation Officials' Manual for Assessing Safety Hardware (MASH).   The FHWA Memorandum "Identifying Acceptable Highway Safety Features" of July 25, 1997 provides further guidance on crash testing requirements of roadside safety 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, Luminaries and Traffic Signals.
**Discussion**
 On June 1, 2011, Trinity Highway Products, LLC purchased the Sign Support business segment from Northwest Pipe and has subsequently moved the manufacturing from Houston, TX to the Trinity facility located in Fort Worth, TX.  Trinity will begin producing product from this facility and you requested that the below referenced letters be transferred to Trinity Highway Products, LLC.  The current letters are:
Letter Number
  Date
  Principal product covered by the letterSS-164
  6/18/2010
  Poz-Loc 10 inch square slip base systemSS-152
  8/23/2007
  PSST posts with 30-inch anchorsSS-150R
  9/5/2008
  Poz-Loc 8 inch square slip base systemSS-130
  1/5/2006
  Triangular slip base casting 16819SS-128R
  9/5/2008
  Poz-Loc slip base casting 28339SS-126A
  11/24/2010
  "Performance Post"SS-126R
  9/5/2008
  PSST postsSS-119
  2/27/2003
  (Correct letter numbering)SS-117
  11/13/2003
  Poz Loc S-Q Post; PozLoc system with  extended anchor; PozLoc breakaway mailbox system for snow regionsSS-88
  8/15/2000
  PSST postsSS-65B
  12/3/1997
  Poz Loc Slip Base SystemSS-65A
  6/25/1997
  Poz Loc Slip Base System and Poz Loc  yielding systemSS-65
  9/5/1996
  Poz Loc Slip Base SystemSS-01A
  7/14/1986
  Poz Loc anchor systemSS-Ol
  5/13/1986
  Poz Loc anchor systemThese letters detail breakaway sign support systems that have been found crashworthy, and are eligible for reimbursement under the Federal-aid highway program.  As Trinity Highway Products now owns the sign support business segment of Northwest Pipe, these products will continue to be eligible if they meet the same specifications, dimensions, material chemistries and mechanical properties as the crash tested devices.
**Findings**
 The systems detailed in the letters listed above continue to be eligible for reimbursement and should be installed under the range of conditions tested, when such use is acceptable to a highway agency.
Please note the following standard provisions that apply to FHWA eligibility letters:
This finding of eligibility is limited to the crashworthiness characteristics of the systems 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 system will require a new letter.
 Should the FHWA discover that the qualification testing was flawed, that in-service performance reveals unacceptable safety problems, or that the system being marketed is significantly different from the version that was crash tested, we reserve the right to modify or revoke this letter.
 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 review, and that it will meet the crashworthiness requirements of the FHWA and the NCHRP Report 350.
 To prevent misunderstanding by others, this letter of eligibility is designated as number SS-174 and shall not be reproduced except in full.  This letter and the test documentation upon which it is based are public information.  All such letters and documentation may be reviewed at our office upon request.
 This letter shall not be construed as authorization or consent by the FHWA to use, manufacture, or sell any patented system for which the applicant is not the patent holder.  The finding of eligibility is limited to the crashworthiness characteristics of the candidate system, and the FHWA is neither prepared nor required to become involved in issues concerning patent law.  Patent issues, if any, are to be resolved by the applicant.
 Some of the Northwest Pipe devices are patented products and considered proprietary.  If proprietary systems are specified by a highway agency for use on Federal-aid projects, except exempt, non-NHS projects, (a) they must be supplied through competitive bidding with equally suitable unpatented items; (b) the highway agency must certify that they are essential for synchronization with the 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 635.411Sincerely yours,
 
 */* Signature of Michael S. Griffith */*
 
 Michael S. Griffith
 Director, Office of Safety Technologies
 Office of SafetyEnclosures U.S. DEPARTMENT OF TRANSPORTATION

**Federal Highway Administration**

1200 NEW JERSEY AVENUE, SE

WASHINGTON, DC 20590

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