ASTM_C_870_-_11_2017.pdf

Designation:C87011(Reapproved 2017)Standard Practice forConditioning of Thermal Insulating Materials1This standard is issued under the fixed designation C870;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 practice covers the conditioning of thermal insu-lating materials for tests.Since prior exposure of insulatingmaterials to high or low humidity will affect the equilibriummoisture content,a procedure is also given for preconditioningthe materials.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 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 and health practices and determine the applica-bility of regulatory limitations prior to use.1.4 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:2C168 Terminology Relating to Thermal InsulationE41 Terminology Relating To ConditioningE171 Practice for Conditioning and Testing Flexible BarrierPackagingE337 Test Method for Measuring Humidity with a Psy-chrometer(the Measurement of Wet-and Dry-Bulb Tem-peratures)2.2 ISO Standard:3ISO 544 Standard Atmospheres for Conditioning and/orTesting3.Terminology3.1 DefinitionsDefinitions of terms in the field of thermalinsulating materials are given in Terminology C168.Thefollowing definitions are derived from Terminology E41:3.1.1 moisture contentthe moisture present in a material,as determined by definite prescribed methods,expressed as apercentage of the mass of the sample on either of the followingbases:(1)original mass(see 3.1.1);(2)moisture-free weight(see 3.1.2).3.1.1.1 DiscussionThis is variously referred to as mois-ture content,or moisture“as is”or“as received.”3.1.1.2 DiscussionThis is also referred to as moistureregain(frequently contracted to“regain”),or moisture contenton the“oven-dry,”“moisture-free,”or“dry”basis.3.1.2 moisture equilibriumthe condition reached by asample when the net difference between the amount of mois-ture sorbed and the amount desorbed,as shown by a change inmass,shows no trend and becomes insignificant.3.1.2.1 DiscussionSuperficial equilibrium with the film ofair in contact with the specimen is reached very rapidly.Stableequilibrium can be reached in a reasonable time only if the airto which the sample is exposed is in motion.Stable equilibriumwith air in motion is considered to be realized when successiveweighings do not show a progressive change in mass greaterthan the tolerances established for the various insulatingmaterials.3.1.3 moisture regainthe moisture in a material deter-mined under prescribed conditions,and expressed as a percent-age of the mass of the moisture-free specimen.3.1.3.1 DiscussionMoisture regain calculations are com-monly based on the mass of a specimen that has been dried byheating in an oven.If the air in the oven contains moisture,theoven-dried specimen will contain some moisture even when itno longer shows a significant change in mass.In order toensure that the specimen is moisture-free,it must be exposed todesiccated air until it shows no further significant change in its1This practice is under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.31 on Chemical andPhysical Properties.Current edition approved April 15,2017.Published May 2017.Originallyapproved in 1977.Last previous edition approved in 2011 as C870 11.DOI:10.1520/C0870-11R17.2For 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 National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.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 Organizat