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Metric Publications

federal-registerFederal Register Notice
FR 28432-28433 PDF
Edition: May 16, 2008

Together NIST SP 330 and NIST SP 811 provide the legal interpretation of and guidelines for the use of the SI in the United States, as described in the Interpretation of the International System of Units (the Metric System of Measurement) for the United States

SP330coverThe International System of Units (SI)
Edition: 2008

This 2008 edition of NIST Special Publication (SP) 330 is the United States version of the English text of the eighth edition of the Bureau International des Poids et Mesures (BIPM) SI Brochure (the most current) published in 2006. SP 330:2008 contains a few minor differences to reflect the most recent interpretation of the SI for the United States by the Secretary of Commerce, as published in the Federal Register of May 16, 2008 (73 FR 28432-28433). The 2008 edition of NIST SP 330 replaces its immediate predecessor, the 2001 edition.

SP811cvrGuide for the Use of International System of Units (SI)
Edition: 2008

This document gives the rules and style conventions for printing and using units, unit symbols and SI prefix symbols. The publication includes an editorial checklist for reviewing manuscripts' conformity with the SI and the basic principles of physical quantities and units. Appendix A provides the definitions of the SI base units. Appendix B gives conversion factors for converting values of quantities expressed in units that are mainly unacceptable to use with the SI to values expressed mainly in units of the SI. Appendix B also includes a simplified discussion of rounding numbers and rounding converted numerical values of quantities. This 2008 edition supersedes NIST Special Publication 811, 1995 Edition, April 1995.

NIST SP 811 SI Diagram PDF

The NIST SP 811 SI Diagram illustrates the utilization of the SI base units in defining the 22 derived units with special names and symbols.

SP1038cvrThe International System of Units (SI) - Conversion Factors for General Use
Edition: 2006

This publication lists the units of the International System of Units (SI), or metric system, recommended for use in trade and commerce and other general uses by the National Institute of Standards and Technology.

1137cvrMetric Style Guide
NIST LC 1137
Edition: 1997

The "Metric Style Guide" addresses how to use metric units in written and verbal communication by addressing the metric prefixes, proper spelling of terms, how to make conversions, use of symbols, plurals, pronunciation, and decimal points. Note: To request a hard copy, please contact the Metric Program.

1136tnThe United States and The Metric System (A Capsule History)
Edition: 1997

Publication gives the history of the metric system in the United States in an abbreviated format. The publication also contains a Q&A section discussing the most common questions about the metric system, a recipe for Chocolate Chip Cookies metric style, as well as, examples of the metric measurement units, and common metric conversion factors. This is an ideal publication for classroom use.

us-man-met-stands-cvrU.S. Manufactures with Product Conforming to Metric Standards: An Analysis PDF
Edition: 1999

This report, prepared for the Metric Program, at the National Institute of Standards and Technology, of the U.S. Department of Commerce,is the result of research into and analysis of the unique data on U.S. manufacturers maintained by the Thomas Publishing Company.

The purpose of this research and analysis is to provide the Metric Program with insights as to the current extent of compliance to metric standards among U.S. industrial product manufacturers. This report gives a "snapshot" of the degree of availability of metric standard products of interest to original equipment manufacturers serving both domestic and overseas markets.

Note: To request hard copies of NIST SI publications, contact the Metric Program.



siglobeSI Teachers Kit: Obtain a free set of metric education resources for your classroom by contacting (include your name, school, subject, grade level, phone number, and mailing address).

FAQ: How do I get a metric ruler?

Metric rulers are available from many retail vendors, which can be identified by using search terms such as "metric rule," "meter stick," or "metric stick." Printable rulers, such as the centimeter Color-square rules, can be color printed on to overhead transparency sheets to make inexpensive metric rulers.