šŸ”„šŸ”„ Donā€™t Miss Out on Our End of Autumn Sale. If you have any questions, feel free to click the bottom right corner to contact our customer service..

Concat us[email protected]
Shopping Cart

No products in the cart.

šŸ”
BS ISO 21748:2017

BS ISO 21748:2017

$198.66

Guidance for the use of repeatability, reproducibility and trueness estimates in measurement uncertainty evaluation

Published By Publication Date Number of Pages
BSI 2017 52
PDF Format Searchable Printable Preview Now
Guaranteed Safe Checkout
Category:

If you have any questions, feel free to reach out to our online customer service team by clicking on the bottom right corner. Weā€™re here to assist you 24/7.
Email:[email protected]

This document gives guidance for

  • evaluation of measurement uncertainties using data obtained from studies conducted in accordance with ISO 5725ā€‘2, and

  • comparison of collaborative study results with measurement uncertainty (MU) obtained using formal principles of uncertainty propagation (see Clause 14).

ISO 5725ā€‘3 provides additional models for studies of intermediate precision. However, while the same general approach may be applied to the use of such extended models, uncertainty evaluation using these models is not incorporated in this document.

This document is applicable to all measurement and test fields where an uncertainty associated with a result has to be determined.

This document does not describe the application of repeatability data in the absence of reproducibility data.

This document assumes that recognized, non-negligible systematic effects are corrected, either by applying a numerical correction as part of the method of measurement, or by investigation and removal of the cause of the effect.

The recommendations in this document are primarily for guidance. It is recognized that while the recommendations presented do form a valid approach to the evaluation of uncertainty for many purposes, it is also possible to adopt other suitable approaches.

In general, references to measurement results, methods and processes in this document are normally understood to apply also to testing results, methods and processes.

PDF Catalog

PDF Pages PDF Title
2 National foreword
7 Foreword
9 Introduction
11 1 Scope
2 Normative references
3 Terms and definitions
15 4 Symbols
17 5 Principles
5.1 Individual results and measurement process performance
5.2 Applicability of reproducibility data
18 5.3 Basic equations for the statistical model
19 5.4 Repeatability data
6 Evaluating uncertainty using repeatability, reproducibility and trueness estimates
6.1 Procedure for evaluating measurement uncertainty
20 6.2 Differences between expected and actual precision
7 Establishing the relevance of method performance data to measurement results from a particular measurement process
7.1 General
7.2 Demonstrating control of the laboratory component of bias
7.2.1 General requirements
7.2.2 Methods of demonstrating control of the laboratory component of bias
23 7.2.3 Detection of significant laboratory component of bias
7.3 Verification of repeatability
7.4 Continued verification of performance
8 Establishing relevance to the test item
8.1 General
24 8.2 Sampling
8.2.1 Inclusion of sampling process
8.2.2 Inhomogeneity
8.3 Sample preparation and pre-treatment
8.4 Changes in test-item type
8.5 Variation of uncertainty with level of response
8.5.1 Adjusting sR
25 8.5.2 Changes in other contributions to uncertainty
9 Additional factors
26 10 General expression for combined standard uncertainty
11 Uncertainty budgets based on collaborative study data
28 12 Evaluation of uncertainty for a combined result
13 Expression of uncertainty information
13.1 General expression
13.2 Choice of coverage factor
13.2.1 General
13.2.2 Level of confidence desired
13.2.3 Degrees of freedom associated with the estimate
29 14 Comparison of method performance figures and uncertainty data
14.1 Basic assumptions for comparison
14.2 Comparison procedure
30 14.3 Reasons for differences
31 AnnexĀ A (informative) Approaches to uncertainty evaluation
36 AnnexĀ B (informative) Experimental uncertainty evaluation
37 AnnexĀ C (informative) Examples of uncertainty calculations
47 Bibliography

Related products

BS ISO 21748:2017
$198.66