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Safety Eligibility Letter B-114A

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U.S. Department of Transportation
Federal Highway Administration

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

Jun 13, 2013

In Reply Refer To: HSST/B-114A

Mr. Ernest Knight
P.O. Box Z
Carlisle, Iowa 50047

Dear Mr. Knight:

This letter is in response to your request for the Federal Highway Administration (FHWA) to review a roadside safety system for eligibility for reimbursement under the Federal-aid highway program.

Name of system: DuroBlock Spacer
Type of system: Recycled Rubber Spacer Block for Guardrail
Test Level: NCHRP Report 350 Test Level 3
Testing conducted by: N/A
Date of request: March 27, 2013
Date to final package March 27, 2013

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

Based on a review of crash test results submitted by the manufacturer certifying the device described herein meets the crash test and evaluation criteria of the National Cooperative Highway Research Program (NCHRP) Report 350, the device is 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.

The FHWA, the Department of Transportation, and the United States Government do not endorse products or services and the issuance of a reimbursement eligibility letter is not an endorsement of any product or service.

To be found eligible for Federal-aid funding, roadside safety devices should meet the crash test and evaluation criteria contained in the NCHRP Report 350 or the American Association of State Highway and Transportation Officials’ Manual for Assessing Safety Hardware (MASH).

The device and supporting documentation are described in the attached form and previous FHWA Letter B-114 to Welch Products, Inc. dated March 27, 2003, copy enclosed for reference. We understand you have acquired the rights to manufacture the Welch offset block.

Summary and Standard Provisions
Therefore, the system described and detailed in the attached form is eligible for reimbursement and may be installed under the range of conditions tested.

Please note the following standard provisions that apply to FHWA eligibility letters:


Sincerely yours,

/* Signature of Michael S. Griffith */
Michael S. Griffith
Director, Office of Safety Technologies
Office of Safety


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Request for Federal Aid Reimbursement Eligibility
Of Highway Safety Hardware

Submitter Date of Request: March 27, 2013    New   Resubmission
Name: Ernest Knight
Company: NPCG, LLC formerly Welch Products, Inc.
Address: PO Box Z, Carlisle,IA 50047
To: Michael S. Griffith, Director
FHWA, Office of Safety Technologies

I request the following devices be considered eligible for reimbursement under the Federal-aid highway program.

System Type Submission Type Device Name/Variant Testing Criterion Test Level
'CC': Crash Cushions, Attenuators, & Seleted Radio Button Physical Crash Testing
Radio Button FEA & V&V Analysis
DuroBlock Spacer NCHRP Report 350 TL3

By submitting this request for review and evaluation by the Federal Highway Administration, I certify that the product(s) was (were) tested in conformity with the NCHRP Report 350 (Report 350) and that the evaluation results meet the appropriate evaluation criteria in the Report 350.

Identification of the individual or organization responsible for the product:

Contact Name: Ernest Knight Same as Submitter ☒
Company Name: NPCG, LLC formerly Welch Products, Inc. Same as Submitter ☒
Address 1: PO Box Z Carlisle, IA 50047 Same as Submitter ☒
Country: USA Same as Submitter ☒


Radio Button New Hardware    Selected Radio ButtonModification to Existing Hardware Non-Significant – Effect is positive or Inconsequential
Requesting company and product name change from Welch Products recycled rubber spacer block to NPCG,
LLC , DuroBiock Spacer


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A brief description of each crash test and its result:

Required Test Number Narrative Description Evaluation Results
3-30 (820C)   PASS
S3-30 (700C)    
3-31 (2000P)    
3-32 (820C)    
S3-32 (700C)    
3-33 (2000P)    
3-34 (820C)    
S3-34 (2000P)    
3-35 (2000P)    
3-36 (700C)    
S3-36 (700P)    
3-37 (2000P)    
3-38 (2000P)    
3-39 (2000P)    
3-40 (2000P)    
3-41 (2000P)    
3-42 (820C)    
3S-42 (700C)    
3-43 (2000P)    
3-44 (2000P)    

Full Scale Crash Testing was done in compliance with MASH by the following accredited crash test laboratory (cite the laboratory's accreditation status as noted in the crash test reports.):

Laboratory Name: Midwest Roadside Safety Facility
Laboratory Contact: Karla Lechtenberg, MSME, EIT Same as Submitter ☐
Address: 130 Whittier Bid., 2200 Vine St., Lincoln, NE 68583—853 Same as Submitter ☐
Country: USA Same as Submitter ☐
Accreditation Certificate
Number and Date:
2937.01 Valid until Nov. 30, 2013


Attach to this form:

  1. 1) A copy of the fu ll test report, video, and a Test Data Summary Sheet for each test conducted in support of this request.
  2. 2) A drawing or drawings of the device(s) that conform to the Task Force-13 Drawing Specifications [Hardware Guide Drawing Standards]. For proprietary products, a single isometric line drawing is usually acceptable to illustrate the product, with detailed specifications, intended use, and contact information provided on the reverse. Additional drawings (not in TF-13 format) showing details that are key to understanding the performance of the device should also be submitted to facilitate our review.

FHWA Official Business Only:

Eligibility Letter AASHTO TF13 Key Words
Number Date Designator


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