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Subject: INFORMATION: Update on Metric Use Requirements for FHWA Documents Date: November 25, 2008
From: Jeffrey F. Paniati
Executive Director
Refer To: HIPA
To: Associate Administrators
Chief Counsel
Acting Chief Financial Officer
Directors of Field Services
Federal Lands Highway Division Engineers
Acting Resource Center Director
Division Administrators

The FHWA is modifying its policy on the use of metric measurements in its daily activities. The use of metric measurements will now be optional in all FHWA documents, including letters, memoranda, publications, reports, and information on FHWA Web sites.

The FHWA has long supported the conversion to metric measurements. Consistent with Section 5164 of the Omnibus Trade and Competitiveness Act of 1988 and Executive Order 12770, issued by President George H. W. Bush on July 25, 1991, we developed a 5-year Metric Conversion Plan for highway documents and plans. By 1995, the vast majority of State departments of transportation (DOT) indicated they would comply with FHWA's conversion completion date of September 30, 1996. As a result, they expended considerable financial resources to convert design, contracting, and other documents, such as Standard Specifications, from the inch-pound system to metric measurements in compliance with the Metric Conversion Plan.

For the Federal-aid highway program, the momentum established by the plan came to an end in 1995. Section 205(c)(2) of the National Highway System (NHS) Designation Act of 1995 prohibited us from requiring any State DOT to use the metric system during project development activities. Although the State DOT's had the option of using metric measurements or dual units (metrics/inch-pounds), all of them abandoned metric measurements and reverted to sole use of inch-pound values.

Our most recent guidance on this subject was contained in a memorandum dated June 1, 2001 (posted at https://www.fhwa.dot.gov/programadmin/contracts/0601metr.cfm). It explained that Section 5164 of the 1988 Act requires all Federal Agencies to use the metric system in their procurements, grants, and other business-related activities except to the extent that such use is impractical or is likely to cause significant inefficiencies or loss of markets to United States firms. Therefore, FHWA continued to use metric measurements in our daily business activities except in documents intended for a broader audience, such as the general public, when dual units (metric values followed by the inch-pound value in parenthesis) were appropriate.

Given that all our partners have abandoned metric measures, we have concluded that continued mandatory use of metric measurements in FHWA's daily business activities is impractical. Accordingly, I am rescinding the prior guidance, dated June 1, 2001, on this issue. The use of metric measurements is no longer mandatory in our daily business activities. Each office may use its own judgment on the value of metric measurements or dual units based on the audience for each document. For offices that wish to use dual units, we encourage a reversal of past practice by presenting them in the format of inch-pound value followed by metric value in parenthesis.

Under the NHS Designation Act, State transportation officials may continue to decide whether to prepare documents using the inch-pound system, metric measurements, or dual measurements. This flexibility applies to all documents developed in compliance with Federal-aid requirements, including the National Environmental Policy Act and other environmental requirements.

If you have any questions, please contact Mr. Edwin Okonkwo at 202-366-1558 of the Office of Program Administration.

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