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This memo is replaced by the November 25, 2008 memo "Update on Metric Use Requirements for FHWA Documents"

Subject: INFORMATION: Update on Metric Use Requirements Date: June 1, 2001
From: /s/ Original signed by:
Vincent F. Schimmoller
Deputy Executive Director
Refer To: HIPA
To: Resource Center Directors
Division Administrators
Federal Lands Highway Division Engineers

This is to let you know about changes in our policy on the use of metric measurements in documents prepared by the State departments of transportation for Federal-aid highway projects.

In the future, the use of metric measurements in documents prepared by the State DOT's will be optional. I am, therefore, rescinding the following prior guidance memoranda on this issue:

"Metric Conversion in Environmental Documents," December 13, 1993.
"Metric Use Requirements," May 6, 1999.

We are not, however, changing our policy on the use of metric measurements in documents prepared by the FHWA. In accordance with the Omnibus Trade and Competitiveness Act of 1988 (Public Law 100-418), we will continue to use metric measurements in our daily business activities. As in the past, documents intended for a broader audience, such as the general public, may use dual units with the metric value first followed by the inch-pound value in parenthesis.

The change in guidance resulted from inquiries by several State DOT's. Following a recent inquiry from the Washington State Department of Transportation regarding environmental documents, I asked the Office of Chief Counsel to review our policy requiring the use of dual measurements. Chief Counsel based its review on Section 205(c)(2) of the National Highway System Designation Act of 1995, which prohibits us from requiring any State to use the metric system "... with respect to designing or advertising, or preparing plans, specifications, estimates, or other documents, for a Federal-aid highway project..." before September 30, 2000 (emphasis added). Section 1211(d) of the Transportation Equity Act for the 21st Century deleted the date of September 30, 2000, making the exception permanent.

Although there is some value in the use of dual measurements, we have concluded that Section 205(c)(2), as amended, gives us sufficient flexibility to let State transportation officials decide whether to prepare documents using the inch-pound system, metric measurements, or dual measurements. The reference to "other documents" covers not only environmental documents but all reports and documents prepared by the States for the FHWA. These documents include planning and research funded grants and forms such as FHWA-45 (Bid Price Statistics) and FHWA-47 (Record of Materials, Supplies, and Labor).

This memorandum also clarifies a portion of our letter dated October 22, 1998, to the chief executive officer of each State transportation department concerning the impact of TEA-21 on metric conversion. Please let the State DOT's know of the change in guidance.

If you have any questions on this matter, please contact Ms. Carol Jacoby at 202-366-1561 or Mr. Edwin Okonkwo at 202-366-1558, both of the Office of Program Administration.

The Office of Program Administration has received questions about whether FHWA will authorize Federal funds to reinburse a State for the cost to convert back to English units. FHWA will not authorize a Federal-aid project to fund the conversion of design processes, information systems, standard specifications, etc. from metric to english. However, the cost of converting these items from metric to english are eligible business costs of a State agency and are therefore eligible for inclusion in the State's indirect costs that may be applied to Federal-aid projects in accordance with TEA-21.

Updated: 06/27/2017
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000