ASTM G141-09(2021)
(Guide)Standard Guide for Addressing Variability in Exposure Testing of Nonmetallic Materials
Standard Guide for Addressing Variability in Exposure Testing of Nonmetallic Materials
SIGNIFICANCE AND USE
4.1 Many standards and specifications reference exposure tests performed according to standards that are the responsibility of Committee G03 on Durability of Nonmetallic Materials. In many cases, use of the data generated in these tests fails to consider the ramifications of variability in the exposure test practices. This variability can have a profound effect on the interpretation of results from the exposure tests, and if not taken into consideration in test design and data analysis, can lead to erroneous or misleading conclusions. This guide lists some of the sources for test variability and recommends strategies for executing successful weathering studies. Not all sources of variability in weathering testing are addressed in this guide. Specific materials, sampling procedures, specimen preparation, specimen conditioning, and material property measurements can contribute significantly to variability in weathering test results. Many of these concerns are addressed in Guide G147. To reduce the contribution of an instrumental method to test variability, it is essential to follow appropriate calibration procedures and ASTM standards associated with the particular property measurement. Additional sources of variability in test results are listed in Guide D4853, along with methods for identifying probable causes.
SCOPE
1.1 This guide covers information on sources of variability and strategies for its reduction in exposure testing, and for taking variability into consideration in the design, execution, and data analysis of both exterior and laboratory accelerated exposure tests.
1.2 The values stated in SI units are to be regarded separately as the standard. The inch-pound values given in parentheses are for information only.
1.3 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.
1.4 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.
General Information
Relations
Standards Content (Sample)
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.
Designation: G141 − 09 (Reapproved 2021)
Standard Guide for
Addressing Variability in Exposure Testing of Nonmetallic
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Materials
This standard is issued under the fixed designation G141; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
No experimental procedure is exactly repeatable or reproducible. Exposure testing is susceptible to
poor test reproducibility because of many contributing factors. These include the type of material and
its homogeneity, the complexity and variability of the outdoor environment, difficulty in precisely
controllingthelaboratorytestingenvironment,andthevariabilityinthemeasurementofperformance.
It is extremely difficult to compare “absolute data,” that is, color shift, gloss, tensile, and elongation,
andsoforth,fromdifferentexposuretests.Thisistruefornaturalandacceleratedexposuresconducted
outdoors or for accelerated exposure tests conducted at different times in one laboratory or comparing
results between laboratories. The purpose of this guide is to provide the user with background
information on test variability and guidance to conduct an exposure test that will provide valid and
useful durability information.
1. Scope* 2. Referenced Documents
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1.1 This guide covers information on sources of variability 2.1 ASTM Standards:
and strategies for its reduction in exposure testing, and for D4853 Guide for Reducing Test Variability (Withdrawn
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taking variability into consideration in the design, execution, 2008)
and data analysis of both exterior and laboratory accelerated D6631 Guide for Committee D01 for Conducting an Inter-
exposure tests. laboratory Study for the Purpose of Determining the
Precision of a Test Method
1.2 The values stated in SI units are to be regarded sepa-
E177 Practice for Use of the Terms Precision and Bias in
rately as the standard. The inch-pound values given in paren-
ASTM Test Methods
theses are for information only.
E691 Practice for Conducting an Interlaboratory Study to
1.3 This standard does not purport to address all of the
Determine the Precision of a Test Method
safety concerns, if any, associated with its use. It is the
G7 Practice for Atmospheric Environmental Exposure Test-
responsibility of the user of this standard to establish appro-
ing of Nonmetallic Materials
priate safety, health, and environmental practices and deter-
G24 Practice for Conducting Exposures to Daylight Filtered
mine the applicability of regulatory limitations prior to use.
Through Glass
1.4 This international standard was developed in accor-
G90 Practice for Performing Accelerated Outdoor Weather-
dance with internationally recognized principles on standard-
ing of Materials Using Concentrated Natural Sunlight
ization established in the Decision on Principles for the
G113 Terminology Relating to Natural andArtificial Weath-
Development of International Standards, Guides and Recom-
ering Tests of Nonmetallic Materials
mendations issued by the World Trade Organization Technical
G147 Practice for Conditioning and Handling of Nonmetal-
Barriers to Trade (TBT) Committee.
lic Materials for Natural and Artificial Weathering Tests
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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This guide is under the jurisdiction of ASTM Committee G03 on Weathering contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
andDurabilityandisthedirectresponsibilityofSubcommitteeG03.93onStatistics. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved July 1, 2021. Published July 2021. Originally approved the ASTM website.
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in 1996. Last previous edition approved in 2013 as G141 – 09(2013). DOI: The last approved version of this historical standard is referenced on
10.1520/G0141-09R21. www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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G141 − 09 (2021)
G151 Practice for Exposing Nonmetallic Materials inAccel- rates of degradation or different degradation mechanisms, it is
erated Test Devices that Use Laboratory Light Sources extremely important to know the characteristics of the expo-
G152 Practice for Operating Open Flame Carbon Arc Light sure sites used and to evaluate materials at sites that produce
Apparatus for Exposure of N
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