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ASTM_D_4442_-_20.pdf
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TM_D_4442_ _20
Designation:D444220Standard Test Methods forDirect Moisture Content Measurement of Wood and Wood-Based Materials1This standard is issued under the fixed designation D4442;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These test methods cover the determination of themoisture content(MC)of wood,veneer,and other wood-basedmaterials,including those that contain adhesives and chemicaladditives.The test procedures appear in the following order:SectionsMethod APrimary Oven-Drying Method5Method BSecondary Oven-Drying Method61.2 The primary oven-drying method(Method A)is in-tended as the sole primary method.It is structured for purposeswhere the highest accuracy or degree of precision is needed(for example,research or calibration).1.3 The secondary oven-drying method(Method B)isintended for the purposes where the primary procedure(Method A)is not desired or justified.Test results in thismethod are generally less precise than in Method A.1.4 For materials that have been chemically treated orimpregnated with creosote,petroleum,and their solutions suchthat the oven-drying procedures introduce greater bias thandesired in the results,other methods,such as AWPA A6,arerecommended.1.5 UnitsThe values stated in SI units are to be regardedas standard.The values given in parentheses after SI units areprovided for information only and are not considered standard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D9 Terminology Relating to Wood and Wood-Based Prod-uctsD4933 Guide for Moisture Conditioning of Wood andWood-Based Materials2.2 Other Standard:AWPA Standard A6 Standard Method for the Determinationof Retention of Oil-Type Preservatives from SmallSamples33.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminology D9.3.1.2 moisture contentamount of water contained in thewood,usually expressed as a percentage of the mass of theoven-dry wood(in accordance with Terminology D9).3.1.2.1 DiscussionThe moisture content of wood or otherwood-based materials can be expressed either as a percentageof oven-dry mass of the sample(oven-dry basis)or as apercentage of the original mass(wet basis).The methodsdescribed in this standard refer to the oven-dry basis.Becauseoven-dry mass is used,moisture content values may exceed100%.The term moisture content when used with wood orother wood-based materials can be misleading since theyfrequently contain varying amounts of volatile compounds(extractives that are evaporated when determining moisturecontent).Definition of the moisture content of wood is furthercomplicated when determined by a thermal method because of1These test methods are under the jurisdiction of ASTM Committee D07 onWood and are the direct responsibility of Subcommittee D07.01 on FundamentalTest Methods and Properties.Current edition approved March 1,2020.Published April 2020.Originallyapproved in 1984.Last previous edition approved in 2016 as D4442 16.DOI:10.1520/D4442-20.These test methods replace,in part,Test Methods D2016,for Moisture Contentof Wood,discontinued 1989.2For 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.3Available from American Wood Protection Association(AWPA),P.O.Box361784,Birmingham,AL 35236-1784,http:/.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.thermal degradation,which causes the final moisture-free massto decrease from small but continuous losses.4.Significance and Use4.1 Moisture content is one of the most important variablesaffecting the properties of wood and wood-based mate

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