ASTM_G_113_-_16.pdf

Designation:G11316Standard TerminologyRelating to Natural and Artificial Weathering Tests ofNonmetallic Materials1This standard is issued under the fixed designation G113;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This terminology standard covers terms that relate to thedurability testing of Nonmetallic Materials using natural andartificial weathering exposure techniques.1.2 It is the intent of this terminology standard to includethose weathering terms in wide use in ASTM for whichstandard definitions appear desirable.2.Referenced Documents2.1 ASTM Standards:2D9 Terminology Relating to Wood and Wood-Based Prod-uctsD4023 Terminology Relating to Humidity Measurements(Withdrawn 2002)3E41 Terminology Relating To ConditioningE772 Terminology of Solar Energy ConversionE973 Test Method for Determination of the Spectral Mis-match Parameter Between a Photovoltaic Device and aPhotovoltaic Reference CellG84 Practice for Measurement of Time-of-Wetness on Sur-faces Exposed to Wetting Conditions as in AtmosphericCorrosion TestingG90 Practice for Performing Accelerated Outdoor Weather-ing of Nonmetallic Materials Using Concentrated NaturalSunlightG201 Practice for Conducting Exposures in Outdoor Glass-Covered Exposure Apparatus with Air Circulation2.2 AATCC Method:416 Colorfastness to Light2.3 ANSI Standards:5ANSI/NCSL Z540-2-1997 American National Standard forExpressing UncertaintyU.S.Guide to the Expression ofUncertainty in MeasurementISO 9370 Plastics-Instrumental Determination of RadiantExposure in Weathering Tests-General Guidance andBasic Test Method3.Significance and Use3.1 This terminology is not intended to supersede therequirements of similar definitions in certain other documents,but is intended to provide a listing of terms that are in currentwidespread usage,and their context in relation to weathering.4.Terminology4.1 Definitions:accelerated outdoor weathering,noutdoor weathering us-ing the sun as the source of irradiance,and where the rate ofdeterioration is accelerated by increasing one or more of theinfluencing parameters above a level obtained in the naturalenvironment.DISCUSSIONExamples of these types of exposures are found inPractice G90 and Practice G201.acceleration factor,nthe ratio of exposure time required toproduce a specified amount of change in a material by oneexposure test divided by the exposure time required toproduce the same change by another exposure test.DISCUSSIONAcceleration factors must be used with great cautionbecause they vary between materials(including different formulationsof the same material)and are strongly dependent on the exposureconditions and variability of both the natural and laboratory acceleratedexposures.Acceleration factors may also vary depending on the level ofmaterial property change used to determine the acceleration factor.Donot ratio irradiance in laboratory accelerated tests to irradiance inoutdoor exposures,or use equivalent radiant exposures to estimate timeto fail in outdoor exposures.These calculations ignore differences intemperature and moisture between the accelerated test and exteriorexposures,and in the spectral power distributions of the laboratory lightsource and sunlight.1This terminology is under the jurisdiction of ASTM Committee G03 onWeathering and Durability and is the direct responsibility of Subcommittee G03.92on Terminology.Current edition approved Dec.1,2016.Published December 2016.Originallyapproved in 1992.Last previous edition approved in 2014 as G113 14.DOI:10.1520/G0113-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American Association of Textile Chemists and Colorists(AATCC),P.O.Box 12215,Research Triangle Park,NC 27709,http:/www.aatcc.org.5Available from National Conference of Standards Laboratories,1800 30th St.,Suite 305B,Boulder,CO 80301.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 actinic radiation,nthe spectral region(s)of a light sourceresponsible for the photodegradation of a particular material.ambient temperature,nthe existing temperature of the airor of an object in thermal equilibrium with the surroundingatmosphere.artificial accelerated irradiation,nexposure of a materialto a laboratory radiation source meant to simulate windowglass filtered solar radiation or radiation from interiorlighting sources and where specimens may be subjected torelatively small changes in temperature and relative humid-ity in an attempt t