The IEEE-SA Standards Board supports IEEE Policy 9.19, which calls for measured and calculated values of quantities to be expressed in metric units in IEEE publications, following the detailed guidance for SI-based metric practice given in IEEE/ASTM Standard SI 10.

Proposed new standards and revised standards submitted for approval should use metric units exclusively in the normative portions of the standard. Inch-pound data may be included in parentheses after the metric units if the Sponsor believes that the audience for the document would benefit from the inclusion of inch-pound data, based on concerns for safety or clarity. Metric units shall always be the primary unit of measurement.

Standards Coordinating Committee 14 (SCC14) shall work with the committees responsible for generating IEEE standards to help them carry out this implementation plan. Policy 9.19 recognizes the need for some exceptions and contains the following statement: "Necessary exceptions to this policy, such as where a conflicting world industry practice exists, must be evaluated on an individual basis and approved by the responsible Major Board of the IEEE for a specific period of time." SCC14, as part of the coordination process, shall review requests for individual exceptions and shall report its recommendations to the IEEE-SA Standards Board.

Exceptions:
(1) Standard SI 10 gives a specific exception for trade sizes, such as the AWG wire series and inch-based standards for fasteners. Such data need not be translated into metric terms.
(2) Also excepted are those cases, such as plugs and sockets, where a mechanical fit to an inch-based product is required.
(3) This Implementation Plan does not require metric products to be substituted for inch-based products.

Approved by IEEE-SA Standards Board
15 September 2006