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The NIST Guide for the Use of the International System of Units (SI)
A. Thompson and B. N. Taylor


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Abbreviated Table of Contents   -   Extended Table of Contents

    Cover
  Preface
  Check List for Reviewing Manuscripts   (Chapter 11)
1. Introduction
  1.1   Purpose of Guide
1.2 Outline of Guide
2. NIST policy on the Use of the SI
  2.1   Essential data
  2.1.1    Tables and graphs
2.2 Descriptive information
3. Other Sources of Information on the SI
  3.1   Publications
3.2 Fundamental Constants Data Center
3.3 Metric Program
4. The Two Classes of SI Units and the SI Prefixes
  4.1   SI base units
4.2 SI derived units
4.2.1     SI derived units with special names and symbols
            4.2.1.1     Degree Celsius
4.2.2     Use of SI derived units with special names and symbols
4.3 Decimal multiples and submultiples of SI units: SI prefixes
5. Units Outside the SI
  5.1   Units accepted for use with the SI
  5.1.1     Hour, degree, liter, and the like
5.1.2     Neper, bel, shannon, and the like
5.1.3     Electronvolt, astronomical unit, and unified atomic mass unit
5.1.4     Natural and atomic units
5.2 Non-SI units accepted for use with the SI
5.3 Units not accepted for use with the SI
  5.3.1     CGS units
5.3.2     Other unacceptable units
5.4 The terms "SI Units" and "acceptable units"
6. Rules and Style Conventions for Printing and Using Units
  6.1   Rules and style conventions for unit symbols
  6.1.1     Typeface
6.1.2     Capitalization
6.1.3     Plurals
6.1.4     Punctuation
6.1.5     Unit symbols obtained by multiplication
6.1.6     Unit symbols obtained by division
6.1.7     Unacceptability of unit symbols and unit names together
6.1.8     Unacceptability of abbreviations for units
6.2 Rules and style conventions for SI prefixes
  6.2.1     Typeface and spacing
6.2.2     Capitalization
6.2.3     Inseparability of prefix and unit
6.2.4     Unacceptability of compound prefixes
6.2.5     Use of multiple prefixes
6.2.6     Unacceptability of stand-alone prefixes
6.2.7     Prefixes and the kilogram
6.2.8     Prefixes with the degree Celsius and units accepted for use with the SI
7. Rules and Style Conventions for Expressing Values of Quantities
  7.1   Value and numerical value of a quantity
7.2 Space between numerical value and unit symbol
7.3 Number of units per value of a quantity
7.4 Unacceptability of attaching information to units
7.5 Unacceptability of mixing information with units
7.6 Symbols for numbers and units versus spelled-out names of numbers and units
7.7 Clarity in writing values of quantities
7.8 Unacceptability of stand-alone unit symbols
7.9 Choosing SI prefixes
7.10 Values of quantities expressed simply as numbers: the unit one, symbol 1
  7.10.1     Decimal multiples and submultiples of the unit one
7.10.2     %, percentage by, fraction
7.10.3     ppm, ppb, and ppt
7.10.4     Roman numerals
7.11 Quantity equations and numerical-value equations
7.12 Proper names of quotient quantities
7.13 Distinction between an object and its attribute
7.14 Dimension of a quantity
8. Comments on Some Quantities and Their Units
  8.1   Time and rotational frequency
8.2 Volume
8.3 Weight
8.4 Relative atomic mass and relative molecular mass
8.5 Temperature interval and temperature difference
8.6 Amount of substance, concentration, molality, and the like
  8.6.1     Amount of substance
8.6.2     Mole fraction of B; amount-of-substance fraction of B
8.6.3     Molar volume
8.6.4     Molar mass
8.6.5     Concentration of B; amount-of-substance concentration of B
8.6.6     Volume fraction of B
8.6.7     Mass density; density
8.6.8     Molality of solute B
8.6.9     Specific volume
8.6.10   Mass fraction of B
8.7 Logarithmic quantities and units: level, neper, bel
8.8 Viscosity
8.9 Massic, volumic, areic, lineic
9. Rules and Style Conventions for Spelling Unit Names
  9.1   Capitalization
9.2 Plurals
9.3 Spelling unit names with prefixes
9.4 Spelling unit names obtained by multiplication
9.5 Spelling unit names obtained by division
9.6 Spelling unit names raised to powers
9.7 Other spelling conventions
9.8 Unacceptability of applying mathematical operations to unit names
10. More on Printing and Using Symbols and Numbers in Scientific and Technical Documents
  10.1   Kinds of symbols
  10.1.1     Standardized quantity symbols
10.1.2     Standardized mathematical signs and symbols
10.2 Typefaces for symbols
  10.2.1     Quantities and variables - italic
10.2.2     Units - roman
10.2.3     Descriptive terms - roman
10.2.4     Sample equations showing correct type
10.3 Greek alphabet in roman and italic type
10.4 Symbols for the elements
  10.4.1     Typeface and punctuation for element symbols
10.4.2     Subscripts and superscripts on element symbols
10.5 Printing numbers
  10.5.1     Typeface for numbers
10.5.2     Decimal sign or marker
10.5.3     Grouping digits
10.5.4     Multiplying numbers
Appendix A Definitions of the SI Base Units
  A.1   Introduction
A.2 Meter
A.3 Kilogram
A.4 Second
A.5 Ampere
A.6 Kelvin
A.7 Mole
A.8 Candela
Appendix B Conversion Factors
  B.1   Introduction
B.2 Notation
B.3 Use of conversion factors
B.4 Organization of entries and style
B.5 Factor for converting motor vehicle efficiency
B.6 U.S. survey foot and mile
B.7 Rules for rounding numbers and converted numerical values of quantities
  B.7.1     Rounding numbers
B.7.2     Rounding converted numerical values of quantities
B.8 Factors for units listed alphabetically
B.9 Factors for units listed by kind of quantity or field of science
Appendix C Comments on the References of Appendix D - Bibliography
  C.1   Defining document for the SI: BIPM SI Brochure
C.2 United States version of defining document for the SI: NIST SP 330
C.3 ISO and IEC
C.4 ANSI/IEEE SI-10
C.5 Federal Register notices
C.6 Federal Standard 376B
C.7 2006 CODATA values of the fundamental constants
C.8 Uncertainty in measurement
Appendix D Bibliography
  Footnotes

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Online: May 1996   -   Last update: July 2008

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