ASTM_F_2638_-_12.pdf

Designation:F263812Standard Test Method forUsing Aerosol Filtration for Measuring the Performance ofPorous Packaging Materials as a Surrogate MicrobialBarrier1This standard is issued under the fixed designation F2638;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 test method measures the aerosol filtration perfor-mance of porous packaging materials by creating a definedaerosol of 1.0 m particles and assessing the filtration effi-ciency of the material using either single or dual particlecounters.1.2 This test method is applicable to porous materials usedto package terminally sterilized medical devices.1.3 The intent of this test method is to determine the flowrate through a material at which maximum penetration occurs.The porous nature of some materials used in sterile packagingapplications might preclude evaluation by means of this testmethod.The maximum penetration point of a particular mate-rial could occur at a flow rate that exceeds the flow capacity ofthe test apparatus.As such,this test method may not be usefulfor evaluating the maximum penetration point of materials witha Bendtsen flow rate above 4000 mL/min as measured byISO 56363.1.4 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.5 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.2.Referenced Documents2.1 ASTM Standards:2E177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standard:3ISO 56363 Paper and BoardDetermination of Air Per-meance(Medium Range)Part 3:Bendtsen Method3.Terminology3.1 Definitions:3.1.1 challenge aerosola sufficient quantity of aerosolized1.0 m particles that enable effective particle counting in thefiltrate aerosol.3.1.2 filtrate aerosolparticles that remain aerosolized afterpassage through the test specimen.3.1.3 maximum penetrationthe highest percent concentra-tion of particles in the filtrate aerosol when a specimen is testedover a range of pressure differentials or air flow rates.3.2 Abbreviations and Symbols:SymbolUnitDescriptionCSnAverage particle count of the challenge aerosolwhen using a single particle counter(Method A).CFnAverage particle count of the filtrate aerosol.CCnAverage particle count of the challenge aerosol.CLRNAverage particle count of the filtrate aerosol prior tocorrection for dilution.R%Percentage of particles from the challenge aerosolthat remain in the filtrate aerosol.RM%The calculated maximum of R.P1cm WCPressure differential across a test specimen due tothe air flow required by the particle counter.Pcm WCPressure differential across a test specimen.FL/m/cm2Air flow rate through the test specimen.F1L/m/cm2Air flow rate required by the particle counter whenmeasuring the filtrate aerosol.FML/m/cm2Air flow rate at which maximum penetration occurs.4.Safety4.1 The waste and the vacuum venturi vents for the testequipment described in this test method emit an aerosol ofpolystyrene particles and salt residues.These aerosols should1This test method is under the jurisdiction ofASTM Committee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee F02.15 onChemical/Safety Properties.Current edition approved May 1,2012.Published June 2012.Originallyapproved in 2007.Last previous edition approved in 2007 as F2638 07.DOI:10.1520/F2638-12.2For 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 States1 be exhausted from any enclosed environment or collected andfiltered to remove all particles.5.Summary of Test Method5.1 A porous packaging material test specimen is placed ina sample holder in such a way as to create a filter between thechallenge and filtrate aerosols.On the challenge side of thesample holder,an aerosol of particles is presented to thesurface of the test specimen.An air flow is generated throughthe test specimen.A laser particle counter is used to monitorthe particle concentrations in the challenge and filtrate aero-sols.Particle concentrations will be measured over a range offlow rates in order to meas