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NIST Technical Note 1297
1994 Edition (Supersedes 1993 Edition)

Web Version History

Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results

Barry N. Taylor and Chris E. Kuyatt

Brief summary

A method of evaluating and expressing uncertainty in measurement adapted from NIST Technical Note 1297.

TN 1297 also available as a PDF file

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(Cover page)
Preface to the 1994 Edition
1. Introduction
2. Classification of Components of Uncertainty
3. Type A Evaluation of Standard Uncertainty
4. Type B Evaluation of Standard Uncertainty
5. Combined Standard Uncertainty
6. Expanded Uncertainty
7. Reporting Uncertainty
8. References
   A: Law of Propagation of Uncertainty
   B: Coverage Factors
   C: Statements of Uncertainty Associated with Measurement Results
D: Clarification and Additional Guidance
D.1 Terminology
D.2 Identification of uncertainty components
D.3 Equation (A-2)
D.4 Measurand defined by the measurement method; characterization of test methods; simple calibration
D.5 tp and the quantile t1-α
D.6 Uncertainty and units of the SI; proper use of the SI and quantity and unit symbols
D.7 References