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ASTM E1169-07

(Guide)

Standard Practice for Conducting Ruggedness Tests

Standard Practice for Conducting Ruggedness Tests

SIGNIFICANCE AND USE
A ruggedness test is a special application of a statistically designed experiment. It is generally carried out when it is desirable to examine a large number of possible factors to determine which of these factors might have the greatest effect on the outcome of a test method. Statistical design enables more accurate determination of the factor effects than would be achieved if separate experiments were carried out for each factor. The proposed designs are easy to use and are efficient in developing the information needed for evaluating quantitative test methods.
In ruggedness testing, the two levels for each factor are chosen to use moderate separations between the high and low settings. In general, the size of effects, and the likelihood of interactions between the factors, will increase with increased separation between the high and low settings of the factors.
Ruggedness testing is usually done within a single laboratory on uniform material, so the effects of changing only the factors are measured. The results may then be used to assist in determining the degree of control required of factors described in the test method.
Ruggedness testing is part of the validation phase of developing a standard test method as described in Guide E 1488. It is preferred that a ruggedness test precedes an interlaboratory (round robin) study.
SCOPE
1.1 This practice covers conducting ruggedness tests. The purpose of a ruggedness test is to identify those factors that strongly influence the measurements provided by a specific test method and to estimate how closely those factors need to be controlled.
1.2 This practice restricts itself to designs with two levels per factor. The designs require the simultaneous change of the levels of all of the factors, thus permitting the determination of the effects of each of the factors on the measured results.
1.3 The system of units for this practice is not specified. Dimensional quantities in the practice 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.

General Information

Status
Historical
Publication Date
31-Jul-2007
ICS
19.020 - Test conditions and procedures in general
Technical Committee
E11 - Quality and Statistics
Drafting Committee
E11.20 - Test Method Evaluation and Quality Control
Current Stage
Ref Project

Relations

Replaces
ASTM E1169-02 - Standard Guide for Conducting Ruggedness Tests
Effective Date
01-Aug-2007
Replaced By
ASTM E1169-12 - Standard Practice for Conducting Ruggedness Tests
Effective Date
01-Nov-2012
Referred By
ASTM E1601-19 - Standard Practice for Conducting an Interlaboratory Study to Evaluate the Performance of an Analytical Method
Effective Date
01-Aug-2007
Referred By
ASTM D7778-15(2022)e1 - Standard Guide for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
Effective Date
01-Aug-2007
Referred By
ASTM E1323-15(2020) - Standard Guide for Evaluating Laboratory Measurement Practices and the Statistical Analysis of the Resulting Data
Effective Date
01-Aug-2007
Referred By
ASTM E1488-12(2023) - Standard Guide for Statistical Procedures to Use in Developing and Applying Test Methods
Effective Date
01-Aug-2007
Referred By
ASTM E3097-23 - Standard Test Method for Uniaxial Constant Force Thermal Cycling of Shape Memory Alloys
Effective Date
01-Aug-2007
Referred By
ASTM E3098-17 - Standard Test Method for Mechanical Uniaxial Pre-strain and Thermal Free Recovery of Shape Memory Alloys
Effective Date
01-Aug-2007
Referred By
ASTM D3670-91(2022) - Standard Guide for Determination of Precision and Bias of Methods of Committee D22
Effective Date
01-Aug-2007
Referred By
ASTM D8064-16 - Standard Test Method for Elemental Analysis of Soil and Solid Waste by Monochromatic Energy Dispersive X-ray Fluorescence Spectrometry Using Multiple Monochromatic Excitation Beams
Effective Date
01-Aug-2007
Referred By
ASTM F2394-07(2022) - Standard Guide for Measuring Securement of Balloon-Expandable Vascular Stent Mounted on Delivery System
Effective Date
01-Aug-2007
Referred By
ASTM E691-23 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
Effective Date
01-Aug-2007
Referred By
ASTM E456-13a(2022) - Standard Terminology Relating to Quality and Statistics
Effective Date
01-Aug-2007
Referred By
ASTM E2653-23 - Standard Practice for Conducting an Interlaboratory Study to Determine Precision Estimates for a Test Method with Fewer Than Six Participating Laboratories
Effective Date
01-Aug-2007
Referred By
ASTM G156-17 - Standard Practice for Selecting and Characterizing Weathering Reference Materials
Effective Date
01-Aug-2007

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ASTM E1169-07 - Standard Practice for Conducting Ruggedness TestsASTM E1169-07 - Standard Practice for Conducting Ruggedness Tests
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ASTM E1169-07 - Standard Practice for Conducting Ruggedness Tests
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Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E1169 − 07 AnAmerican National Standard
Standard Practice for
1
Conducting Ruggedness Tests
This standard is issued under the fixed designation E1169; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 ruggedness, n—insensitivity of a test method to de-
partures from specified test or environmental conditions.
1.1 This practice covers conducting ruggedness tests. The
3.1.1.1 Discussion—An evaluation of the “ruggedness” of a
purpose of a ruggedness test is to identify those factors that
test method or an empirical model derived from an experiment
stronglyinfluencethemeasurementsprovidedbyaspecifictest
isusefulindeterminingwhethertheresultsordecisionswillbe
method and to estimate how closely those factors need to be
relativelyinvariantoversomerangeofenvironmentalvariabil-
controlled.
ity under which the test method or the model is likely to be
1.2 This practice restricts itself to designs with two levels
applied.
per factor. The designs require the simultaneous change of the
3.1.2 ruggedness test, n—a planned experiment in which
levelsofallofthefactors,thuspermittingthedeterminationof
environmental factors or test conditions are deliberately varied
the effects of each of the factors on the measured results.
in order to evaluate the effects of such variation.
1.3 The system of units for this practice is not specified.
3.1.2.1 Discussion—Since there usually are many environ-
Dimensional quantities in the practice are presented only as
mental factors that might be considered in a ruggedness test, it
illustrations of calculation methods. The examples are not
is customary to use a “screening” type of experiment design
binding on products or test methods treated.
which concentrates on examining many first order effects and
1.4 This standard does not purport to address all of the generallyassumesthatsecondordereffectssuchasinteractions
safety concerns, if any, associated with its use. It is the and curvature are relatively negligible. Often in evaluating the
responsibility of the user of this standard to establish appro- ruggedness of a test method, if there is an indication that the
priate safety and health practices and determine the applica- results of a test method are highly dependent on the levels of
bility of regulatory limitations prior to use. the environmental factors, there is a sufficient indication that
certain levels of environmental factors must be included in the
2. Referenced Documents
specifications for the test method, or even that the test method
2
itself will need further revision.
2.1 ASTM Standards:
E456Terminology Relating to Quality and Statistics
3.2 Definitions of Terms Specific to This Standard:
E1325Terminology Relating to Design of Experiments
3.2.1 factor, n—testvariablethatmayaffecteithertheresult
E1488GuideforStatisticalProcedurestoUseinDeveloping
obtainedfromtheuseofatestmethodorthevariabilityofthat
and Applying Test Methods
result.
F2082Test Method for Determination of Transformation
3.2.1.1 Discussion—For experimental purposes, factors
Temperature of Nickel-Titanium Shape Memory Alloys
must be temporarily controllable.
by Bend and Free Recovery
3.2.2 foldover, n—test runs, added to a two-level fractional
factorial experiment, generated by duplicating the original
3. Terminology
design by switching levels of one or more factors in all runs.
3.1 Definitions—The terminology defined in Terminology
3.2.2.1 Discussion—The most useful type of foldover is
E456 applies to this practice unless modified herein.
with signs of all factors switched. The foldover runs are
combined with the initial test results. The combination allows
main effects to be separated from interactions of other factors
1
ThispracticeisunderthejurisdictionofASTMCommitteeE11onQualityand
that are aliased in the original design.
Statistics and is the direct responsibility of Subcommittee E11.20 on Test Method
Evaluation and Quality Control.
Current edition approved Aug. 1, 2007. Published October 2007. Originally
4. Summary of Practice
approved in 1987. Last previous edition approved in 2002 as E1169–02. DOI:
10.1520/E1169-07.
4.1 Conducting a ruggedness test requires making system-
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
atic changes in the variables, called factors, that are associated
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
with the test method and then observing the subsequent effect
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. of those changes upon the test result of each run.
C
...

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4.1 A ruggedness test is a special application of a statistically designed experiment that makes changes in the test method variables, called factors, and then calculates the subsequent effect of those changes upon the test results. Factors are features of the test method or of the laboratory environment that are known to vary across laboratories and are subject to control by the test method.  
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5.1 This guide presents techniques and guidance for evaluating and assuring homogeneity of individual samples or bulk materials and can be used for either interlaboratory or intra-laboratory studies. The types of studies include, but are not limited to, studies to determine precision estimates for test methods, proficiency testing programs, and studies related to quality control of testing within a single laboratory.  
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SCOPE
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1.5 For circumstances when homogeneity testing is not possible, the fifth technique provides guidance for producing homogeneous samples.  
1.6 The appendixes of this guide provide example spreadsheets for Techniques 1, 2, 3, and 4.  
1.7 This guide is not intended for evaluation of certified reference materials (CRMs) or materials used for calibration.  
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Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods

ABSTRACT
The purpose of this practice is to present concepts necessary to the understanding of the terms “precision” and “bias” as used in quantitative test methods. This practice also describes methods of expressing precision and bias and, in a final section, gives examples of how statements on precision and bias may be written for ASTM test methods. A statement of precision allows potential users of a test method to assess in general terms the test method’s usefulness with respect to variability in proposed applications.
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4.1 Part A of the “Blue Book,” Form and Style for ASTM Standards, requires that all test methods include statements of precision and bias. This practice discusses these two concepts and provides guidance for their use in statements about test methods.  
4.2 Precision—A statement of precision allows potential users of a test method to assess in general terms the test method’s usefulness with respect to variability in proposed applications. A statement of precision is not intended to exhibit values that can be exactly duplicated in every user’s laboratory. Instead, the statement provides guidelines as to the magnitude of variability that can be expected between test results when the method is used in one, or in two or more, reasonably competent laboratories. For a discussion of precision, see 8.1.  
4.3 Bias—A statement of bias furnishes guidelines on the relationship between a set of typical test results produced by the test method under specific test conditions and a related set of accepted reference values (see 9.1).  
4.3.1 An alternative term for bias is trueness, which has a positive connotation, in that greater bias is associated with less favorable trueness. Trueness is the systematic component of accuracy.  
4.4 Accuracy—The term “accuracy,” used in earlier editions of Practice E177, embraces both precision and bias (see 9.3).
SCOPE
1.1 The purpose of this practice is to present concepts necessary to the understanding of the terms “precision” and “bias” as used in quantitative test methods. This practice also describes methods of expressing precision and bias and, in a final section, gives examples of how statements on precision and bias may be written for ASTM test methods.  
1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E2554-18e1(Practice)
Standard Practice for Estimating and Monitoring the Uncertainty of Test Results of a Test Method Using Control Chart Techniques

ABSTRACT
This practice describes techniques for a laboratory to estimate the uncertainty of a test result using data from test results on a control sample. This practice provides one method for a laboratory to estimate Measurement Uncertainty in accordance with Section A22.3 in Form and Style for ASTM Standards. 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.
This practice provides one way for a laboratory to develop data-based Type A estimates of uncertainty as referred to in Section A22 in Form and Style for ASTM Standards.
SIGNIFICANCE AND USE
4.1 This practice provides one way for a laboratory to develop data-based Type A estimates of uncertainty as referred to in Section A22 in Form and Style for ASTM Standards.  
4.2 Laboratories accredited under ISO/IEC 17025 are required to present uncertainty estimates for their test results. This practice provides procedures that use test results to develop uncertainty estimates for an individual laboratory.  
4.3 Generally, these test results will be from a single sample of stable and homogeneous material known as a control or check sample.  
4.4 The true value of the characteristic(s) of the control sample being measured will ordinarily be unknown. However, this methodology may also be used if the control sample is a reference material, in which case the test method bias may also be estimated and incorporated into the uncertainty estimate. Many test methods do not have true reference materials available to provide traceable chains of uncertainty estimation.  
4.5 This practice also allows for ongoing monitoring of the laboratory uncertainty. As estimates of the level of uncertainty change, possibly as contributions to uncertainty are identified and minimized, revision to the laboratory uncertainty will be possible.
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. This practice provides one method for a laboratory to estimate Measurement Uncertainty in accordance with Section A22.3 in Form and Style for ASTM Standards.  
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.  
1.8 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, health, and environmenta...

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