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Special Publication 330
The International System of Units (SI) 2019 Edition
This supersedes NIST Special Publication 330, 2008 Edition.
Table of Contents (webpages below) or
PDF version
- 1.1 The SI and the defining constants
- 1.2 Motivation for the use of defining constants to define the SI
- 1.3 Implementation of the SI
2. The International System of Units
3. Decimal multiples and sub-multiples of SI units
4. Non-SI units that are accepted for use with the SI
5. Writing unit symbols and names, and expressing the values of quantities
- 5.1 The use of unit symbols and names
- 5.2 Unit symbols
- 5.3 Unit names
- 5.4 Rules and style conventions for expressing values of quantities
- 5.4.1 Value and numerical value of a quantity, and the use of quantity calculus
- 5.4.2 Quantity symbols and unit symbols
- 5.4.3 Formatting the value of a quantity
- 5.4.4 Formatting numbers, and the decimal marker
- 5.4.5 Expressing the measurement uncertainty in the value of a quantity
- 5.4.6 Multiplying or dividing quantity symbols, the values of quantities, or numbers
- 5.4.7 Stating quantity values being pure numbers
- 5.4.8 Plane angles, solid angles and phase angles
Appendix 1. Decisions of the CGPM and the CIPM
Appendix 2. Practical realization of the definitions of some important units
Appendix 3. Units for photochemical and photobiological quantities
- Part 1. The historical development of the realization of SI units
- Part 2. The historical development of the International System
- Part 3. Historical perspective on the base units
List of acronyms used in the present volume
List of Tables
Table 1. The seven defining constants of the SI and the seven corresponding units they define
Table 2. SI base units
Table 3. Base quantities and dimensions used in the SI
Table 4. The 22 SI units with special names and symbols
Table 5. Examples of coherent derived units in the SI expressed in terms of base units
Table 6. Examples of SI coherent derived units whose names and symbols include SI coherent derived units with special names and symbols
Table 7. SI prefixes
Table 8. Non-SI units accepted for use with the SI units
Contacts
Editors
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