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Consistency Test Suite End-User Package and Acceptable Margin Answer Key For FHWA TNM

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This end-user package is provided electronically to those who wish to provide information to FHWA to show their noise model/application is consistent with the methodology of FHWA TNM 3.0. It contains what variables need to be tested, the tests that need to be completed, instructions on how to use the test suite, and how the FHWA will compare their results to the results that the FHWA considers acceptable. These include simple, moderate, and complex real world test case runs.

This is the answer key that the FHWA will use to evaluate the results from another model to the results from FHWA TNM 3.0. Each variable of each test will have an identified acceptable margin of difference from the FHWA TNM 3.0 results.

The cases in this Consistency Test Suite (CTS) are taken from a larger set of cases developed for this task order and reported in the March 2014 report "Sensitivity Test Case Results Comparing FHWA TNM 2.5 and TNM 3.0". The sensitivity test work compared results between the current FHWA TNM 2.5 and the FHWA TNM 3.0 acoustics core developed by the USDOT Volpe Center’s Acoustics Facility (referred to in that report, this report and the accompanying spreadsheets as Volpe TNM 3.0, or simply Volpe 3.0).

The full CTS and Acceptable Margin Answer Key (AMAK) to be provided to an end-user developer consists of:

The first section of this report is an introduction for the end user. The second section briefly lists the variables to be tested. The third section gives instructions on how to use the test suite. Finally, the fourth section describes in detail the tests that need to be completed.


This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.


1. Report No.


2. Government Accession No.

3. Recipient's Catalog No.

4. Title and Subtitle

Consistency Test Suite End-User Package and Acceptable Margin Answer Key For FHWA TNM 3.0

5. Report Date :

6. Performing Organization Code:

7. Author(s):

William Bowlby, Ph.D., P.E., Rennie L. Williamson, Bowlby & Associates, Inc.

Kenneth Kaliski, P.E., RSG

8. Performing Organization Report No. 11205-2

9. Performing Organization Name and Address


55 Railroad Row

White River Junction VT 05001

10. Work Unit No.

11. Contract or Grant No.


12. Sponsoring Agency Name and Address

U.S. Department of Transportation

Federal Highway Administration

Office of Planning, Environment and Realty

Washington, DC 20590

13. Type of Report and Period Covered

14. Sponsoring Agency Code

15. Supplementary Notes

16. Abstract:

This document describes the Consistency Test Suite End-User Package and Acceptable Margin Answer Key for software developers to use to test how well their implementation of FHWA’s TNM 3.0 conforms with the standard FHWA TNM 3.0 model.

17. Key Words: TNM 3.0, Traffic Noise Model, Consistency Test Suite, Acceptable Margin Answer Key

18. Distribution Statement

19. Security Classification (of this report)

Not classified

20. Security Classification (of this page)

Not Classified

21. No of Pages

22. Price

Form DOT F 1700.7 (8-72)

Reproduction of completed pages authorized

List of acronyms and abbreviations


Acceptable Margin Answer Key


Consistency Test Suite


Edge of Pavement


Federal Highway Administration




Noise Reduction Coefficient


Traffic Noise Model

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Updated: 10/19/2015
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