1. Scope

1.1 This practice describes techniques for a laboratory to estimate the uncertainty of a test result using data from test results on a control sample.

1.2 Uncertainty as defined by this practice applies to the capabilities of a single laboratory. Any estimate of uncertainty determined through the use of this practice applies only to the individual laboratory for which the data are presented.

1.3 The laboratory uses a well defined and established test method in determining a series of test results. The uncertainty estimated using this practice only applies when the same test method is followed. The uncertainty only applies for the material types represented by the control samples, and multiple control samples may be needed, especially if the method has different precision for different sample types or response levels.

1.4 The uncertainty estimate determined by this practice represents the intermediate precision of test results. This estimate seeks to quantify the total variation expected within a single laboratory using a single established test method while incorporating as many known sources of variation as possible.

1.5 This practice does not establish error estimates (error budget) attributed to individual factors that could influence uncertainty.

1.6 This practice describes the use of control charts to evaluate the data obtained and presents a special type of control chart to monitor the estimate of uncertainty.

1.7 The system of units for this Standard is not specified. Dimensional quantities in the Standard are presented only as illustrations of calculation methods. The examples are not binding on products or test methods treated.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ISO Standard

ASTM Standards

D5184 Test Methods for Determination of Aluminum and Silicon in Fuel Oils by Ashing, Fusion, Inductively Coupled Plasma Atomic Emission Spectrometry, and Atomic Absorption Spectrometry

E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods

E456 Terminology Relating to Quality and Statistics

E2282 Guide for Defining the Test Result of a Test Method

ASTM Publication

ManualonPresentation 7th Edition

Keywords

control chart; control sample; intermediate precision; test result; uncertainty;

ICS Code

ICS Number Code 03.120.10 (Quality management and quality assurance); 19.020 (Test conditions and procedures in general)

DOI: 10.1520/E2554-07

ASTM International is a member of CrossRef.