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15 U.S. Code § 205b - Declaration of policy

It is therefore the declared policy of the United States—
to designate the metric system of measurement as the preferred system of weights and measures for United States trade and commerce;
to require that each Federal agency, by a date certain and to the extent economically feasible by the end of the fiscal year 1992, use the metric system of measurement in its 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, such as when foreign competitors are producing competing products in non-metric units;
to seek out ways to increase understanding of the metric system of measurement through educational information and guidance and in Government publications; and
to permit the continued use of traditional systems of weights and measures in non-business activities.
Editorial Notes

1988—Pub. L. 100–418 amended section generally. Prior to amendment, section read as follows: “It is therefore declared that the policy of the United States shall be to coordinate and plan the increasing use of the metric system in the United States and to establish a United States Metric Board to coordinate the voluntary conversion to the metric system.”

Statutory Notes and Related Subsidiaries
Implementation of Metric Usage in Federal Government

Secretary of Commerce designated to direct and coordinate implementation of Government metric usage, see section 1 of Ex. Ord. No. 12770, July 25, 1991, 56 F.R. 35801, set out as a note under section 205a of this title.