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BRITISHSTANDARD
Compressedair—
Part8:Testmethodsforsolidparticlecontentbymassconcentration
ICS71.100.20
NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAW
BSISO
8573-8:2004
Britishstandards
BSISO8573-8:2004
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Nationalforeword
ThisBritishStandardreproducesverbatimISO8573-8:2004andimplementsitastheUKnationalstandard.
TheUKparticipationinitspreparationwasentrustedtoTechnicalCommitteeMCE/8,Compressors,pneumatictools,pneumaticmachinesandvacuum
technology,whichhastheresponsibilityto:
—aidenquirerstounderstandthetext;
—presenttotheresponsibleinternational/Europeancommitteeany
enquiriesontheinterpretation,orproposalsforchange,andkeepthe
UKinterestsinformed;
—monitorrelatedinternationalandEuropeandevelopmentsandpromulgatethemintheUK.
Alistoforganizationsrepresentedonthiscommitteecanbeobtainedonrequesttoitssecretary.
Cross-references
TheBritishStandardswhichimplementinternationalpublicationsreferredtointhisdocumentmaybefoundintheBSICatalogueunderthesectionentitled“InternationalStandardsCorrespondenceIndex”,orbyusingthe“Search”
facilityoftheBSIElectronicCatalogueorofBritishStandardsOnline.
Thispublicationdoesnotpurporttoincludeallthenecessaryprovisionsofacontract.Usersareresponsibleforitscorrectapplication.
CompliancewithaBritishStandarddoesnotofitselfconferimmunityfromlegalobligations.
Summaryofpages
Thisdocumentcomprisesafrontcover,aninsidefrontcover,theISOtitlepage,pagesiitoiv,pages1to8,aninsidebackcoverandabackcover.
TheBSIcopyrightnoticedisplayedinthisdocumentindicateswhenthedocumentwaslastissued.
ThisBritishStandardwas
publishedundertheauthorityoftheStandardsPolicyand
StrategyCommitteeon
17June2004
?BSI17June2004
ISBN0580439607
Amendmentsissuedsincepublication
Amd.No.
Date
Comments
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BSISO8573?8:2004
INTERNATIONAL
STANDARD
ISO
8573-8
Firstedition2004-02-01
Compressedair—
Part8:
Testmethodsforsolidparticlecontentbymassconcentration
Aircomprimé—
Partie8:Méthodesd'essaipourladéterminationdelateneurenparticulessolidesparconcentrationmassique
ReferencenumberISO8573-8:2004(E)
ii
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BSISO8573?8:2004
iii
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BSISO8573?8:2004
Page
Contents
Foreword iv
1Scope
1
2Normativereferences
1
3Termsanddefinitions
1
4Unitsandsymbols
2
5Selectionofmethods
2
6Samplingtechniques
2
7Measurementmethods
3
8Evaluationoftestresults
6
9Uncertainty
6
10Testreport
7
AnnexA(informative)Sampletestreport
8
iv
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BSISO8573?8:2004
Foreword
ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies
(ISOmemberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISO
technicalcommittees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeen
establishedhastherighttoberepresentedonthatcommittee.Internationalorganizations,governmentaland
non-governmental,inliaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththe
InternationalElectrotechnicalCommission(IEC)onallmattersofelectrotechnicalstandardization.
InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part2.
ThemaintaskoftechnicalcommitteesistoprepareInternationalStandards.DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedtothememberbodiesforvoting.PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote.
Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectofpatentrights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.
ISO8573-8waspreparedbyTechnicalCommitteeISO/TC118,Compressors,pneumatictoolsandpneumaticmachines,SubcommitteeSC4,Qualityofcompressedair.
ISO8573consistsofthefollowingparts,underthegeneraltitleCompressedair:
—Part1:Contaminantsandpurityclasses
—Part2:Testmethodsforaerosoloilcontent
—Part3:Testmethodsformeasurementofhumidity
—Part4:Testmethodsforsolidparticlecontent
—Part5:Testmethodsforoilvapourandorganicsolventcontent
—Part6:Testmethodsforgaseouscontaminantcontent
—Part7:Testmethodsforviablemicrobiologicalcontaminantcontent
—Part8:Testmethodsforsolidparticlecontentbymassconcentration
—Part9:Testmethodsforliquidwatercontent
Part2isunderrevision.
1
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BSISO8573?8:2004
Compressedair—
Part8:
Testmethodsforsolidparticlecontentbymassconcentration
1Scope
ThispartofISO8573specifiestestmethodsfordeterminingthesolidparticlemassconcentrationincompressedair,expressedasthemassofsolidparticleswithmaximumparticlesizelimits.Thelimitationsofthemethodsarealsogiven.Oneofaseriesofstandardsaimedatharmonizingaircontaminationmeasurements,itidentifiessamplingtechniquesandalsogivesrequirementsforevaluation,uncertaintyconsiderationsandreportingfortheairpurityparametersolidparticlesbymassconcentration.ThetestmethodsaresuitablefordeterminingpurityclassesinaccordancewithISO8573-1.(ParticlecontentbasedoncountingparticlesisdealtwithinISO8573-4.)
2Normativereferences
Thefollowingreferenceddocumentsareindispensablefortheapplicationofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.
ISO1219-1,Fluidpowersystemsandcomponents—Graphicsymbolsandcircuitdiagrams—Part1:Graphicsymbols
ISO3857-1,Compressors,pneumatictoolsandmachines—Vocabulary—Part1:General
ISO5598,Fluidpowersystemsandcomponents—Vocabulary
ISO8573-1,Compressedair—Part1:Contaminantsandpurityclasses
ISO8573-2,Compressedair—Part2:Testmethodsforaerosoloilcontent
ISO8573-4,Compressedair—Part4:Testmethodsforsolidparticlecontent
3Termsanddefinitions
Forthepurposesofthisdocument,thetermsanddefinitionsgiveninISO3857-1,ISO5598,ISO8573-1andISO8573-4apply.
2
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BSISO8573?8:2004
4Unitsandsymbols
ForthepurposesofthispartofISO8573,thefollowing,includingnon-SI-preferred,unitsareused:
—1bar=100000Pa;
—1l(litre)=0,001m3;
—bar(a),usedforexpressingabsolutepressure;
—bar(e),usedforexpressingeffectivepressure.
ForthegraphicsymbolsusedinFigure1,seeISO1219-1.
5Selectionofmethods
Thegravimetricmethodtobeusedissuitableformassconcentrationmeasurement,however,wherewaterandoilispresentinthecompressedair,itshallbereducedtoaminimum.
AsuitablemethodforsolidparticlediametermeasurementmaybeselectedfromthosegiveninTable1.
Table1—Solidparticlediametermeasurementmethods
Typeofmethod
Maximumsolidparticlediameter
d
μm
Liquidwaterandoilcontaminant
mg/m3
Microscopemethod
d>0,5
<20
Particlesizermethod
0,1<d<40
Notadmitted
6Samplingtechniques
Thesamplingshallbemadeatorneartheactualpressureandataconstantflowrate.
Thechoiceofsamplingmethodwilldependupontheactuallevelofcontaminationandthecompressedairflowinthecompressedairsystem.Forsamplingmethods,seeISO8573-2andISO8573-4.
Forpartialflowsampling,itshouldbenotedthat,wherelargeparticlesizesareinvolved,theeffectsofgravitycouldintroducesamplingerrors.
Compressedairsamplesmayberoutedbackintothemainpipeorventtotheatmosphereaftermeasurement.Thevalueofairsampleparameters(pressure,temperature,airvelocity,etc.)shallbewithintherangesspecifiedbythetestequipmentmanufacturer.MethodB1usesfullflowsamplingfromthemainpipeflowbymeansofaY-piece.
3
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BSISO8573?8:2004
7Measurementmethods
7.1General
Thetestequipmentandinstrumentsshallbeingoodworkingorder.Considerationshallbegiventothecalibrationrequirementsofthemeasurementequipmentusedasgivenintheapplicableinstructions.
Theindicatedmethodsmaybeusedatanypointinacompressedairsystemusingportableinstrumentswhereconditionsofmeasurementaresatisfiedandavailableconnectorsandshut-offvalvesexistforconnectiontothecompressedairsystem.
Inordertoguaranteetherequiredaccuracyofdeterminationofsolidparticlecontentbythegravimetricmethod,thetotalcontentofwaterandoilaerosolsinthecompressedairsamplingshallbelessthan20mg/m3forsamplingMethodAandlessthan5mg/m3forsamplingMethodsB1andB2.
Referenceshouldbemadetothemeasurementequipmentmanufacturerinrespectoftheapplicabilityoftheequipment.
Thegravimetricmethoddealswiththeseparationandtheweighingofsolidparticlesthatarepresentinacompressedairsample.Theinfluenceoftemperature,pressure,humidityandothercontaminantsofcompressedairshallbetakenintoconsideration.
7.2Testequipment
7.2.1General
Airflowispassedthroughthetestequipmentviasuitablein-linevalveswhichhavebeenpreviouslycheckedtoensuretheydonotcontributetothelevelofcontaminationalreadypresent.
ThegeneralarrangementofthetestequipmentforthegravimetricmethodshallbeinaccordancewithFigure1.
NOTEThenumbersgivenbetweenparenthesesinthesubclausetitlesrefertothenumberingoftheelementsin
Figure1.
Forsymbols,seeISO1219-1.
Key
1samplingpoint
2shut-offvalve
3heater(ifrequired)
4membraneholder
5pressuregauge
6
7
8
910
thermometer
flowcontrolvalve
airflowmeter
shut-offvalve
dischargeoutlet
Figure1—Circuitdiagramoftestequipmentforgravimetricmethod
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BSISO8573?8:2004
7.2.2Membraneholder(4)
Themembraneshallbemanufacturedfromhydrophobichigh-efficiencymaterial.
NOTEForadescriptionofatypicalmembraneanditsholder,seeISO8573-2.
7.2.3Flowcontrolvalve(7)
Inordertoadjusttheflowaccurately,useavalvewithfineadjustment.
7.2.4Pressuregauge(5)
Thepressurevaluesshallberecordedduringtheentireperiodofthetest.
Theaccuracyofmeasurementofthepressureshallbebetterthan±2%ofreading.
7.2.5Thermometer(6)
Thetemperaturevaluesshallberecordedduringtheentireperiodofthetest.
Theaccuracyofmeasurementofthetemperatureshallbebetterthan±1°C.
7.2.6Airflowmeter(8)
Theflowratevaluesshallberecordedduringtheentireperiodofthetest.
Theaccuracyofmeasurementoftheflowrateshallbebetterthan±5%.
7.2.7Pipes,connectors,shut-offvalves(2and9)
Therequirementsforpipes,connectorsandshut-offvalvesshallbeaccordingtoISO8573-2.
7.2.8Heater(3)
Theheatermaybeusedtodecreasethelevelofliquidwaterandoilcontaminantcontentinthecompressedairsampletothevaluespecifiedin7.1.Reducingtheamountofliquidwaterandoilcontentbyheatingand/orthereductionofthepressureofthecompressedairshallnothaveaninfluenceonsolidparticlecontentinthecompressedairsample.
7.3Testprocedure
7.3.1Preparationformeasuring
TheproceduresforpreparationformeasuringshallbeinaccordancewithISO8573-2.Theweightofthedrymembraneshallbedeterminedbeforethesampleistaken.
7.3.2Durationoftest
Theoptimumdurationofthecompressedairsamplingmaybedeterminedafterthefirstproofmeasurementtodeterminethetentativesolidparticleconcentration.
Approximatedurationoftest,t,inminutescanalsobedeterminedbythefollowinginequality:
<t<
mmin
cplimq
m
max
cplimq
(1)
5
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BSISO8573?8:2004
where
mministheminimumrequiredamountofsolidparticlecontentonthemembrane,inmilligrams;
mmaxisthemaximumpermittedamountofsolidparticlecontentonthemembrane,inmilligrams;
Cplimistheassumedormaximumpermittedamountofsolidparticlecontentinthecompressedair,inmilligramspercubicmetre;
qisthecompressedairdischargethroughthemembrane,incubicmetresperminute.
Themassofsolidparticlescollectedonthemembraneshallbeinrange1mg<m<5mgon1cm2ofthemembranesurface.
7.3.3Measurementofsolidparticlemassconcentration
Ifliquidwaterandoilcontaminantsareabsentinthecompressedairflow,thesolidparticlemassconcentrationforeachsampleisdeterminedasadifferencebetweenmassesofthetestmembranebeforeandafterairsampling,dividedbythetotalvolumeofairpassedthroughthemembrane.Afterairsamplingandbeforeweighing,thetestmembraneshouldbeplacedinadesiccatoroverasuitabledesiccant,e.g.silicagel,for10-15minoruntilthemassofmembraneisstable.
Ifthereareliquidwaterandoilcontaminantsinthecompressedairflow,theyshallberemovedafterairsamplingandbeforeweighingofthetestmembrane.Forthispurpose,thetestmembraneshallbeplacedinthedesiccatoroversulphuricacidfor2h.Then,thetestmembraneiscarriedinthechemicalfunnelontheconicalwall(thefiltrateisoverthemembrane),pressedtotheconicwallwiththeglassstickandtreatedseveraltimesbysmallportionsofasuitablesolventoftotalvolume10-15mlfordissolvingandremovingoftheoil.Afterthat,thetestmembraneshallbemaintainedfor2-3minatatemperatureof20-30°Candthenweighed.
Othermethodsforremovalofwaterandoilfromthetestmembranearepermittediftheyhavenoinfluenceonsolidparticlecontentofthetestmembraneaftersamplingthecompressedair.
Themaximumuncertaintyofmeasurementofmassshallbebetterthan±2%.
7.4Calculationofresults
Itisnecessarytoensurethatresultsarestable,repeatableandpresentedinaformthatshowsthattheyareso.Thesolidparticlemassconcentrationcpninmg/m3foreachmeasurementshallbedeterminedbytheformula:
pn
c=
mn?m0
qntn
(2)
where
m0isthemassoftestmembranebeforesampling,inmilligrams;
mnisthemassoftestmembraneaftersampling,inmilligrams;
qnistheflowrateofsamplingairthroughthemembrane,incubicmetresperminute;
tnisthesamplingtime,inminutes.
7.5Determinationofmaximumdiameterofsolidparticles
ThemeasurementmethodsofmaximumdiameterofsolidparticlesidentifiedinTable1shallbecarriedoutinaccordancewithISO8573-4.
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BSISO8573?8:2004
8Evaluationoftestresults
8.1Referenceconditions
Thereferenceconditionsforsolidparticlemassconcentrationvolumestatementsareasfollows:
—Airtemperature:20°C;
—Airpressure:1bar(a);
—Relativewatervapourpressure:0%.
8.2Influenceofhumidity
Themeasuredsolidparticlemassconcentrationshallberecalculatedtorefertothedryairvolumeasgivenbythepartialpressureoftheairatthesamplingpoint.Undernormalconditions,theeffectofhumidityonvolumecanbesmallandtherequirementtocalculateitseffectisusuallynotrequired.
8.3Influenceofpressure
Thesolidparticlemassconcentrationshallberecalculatedtoreferencepressureconditions.
Thesolidparticlemassconcentrationwillvaryindirectproportionintheratioofsystemtosampleabsolutepressure.
8.4Influenceoftemperature
Thesolidparticlemassconcentrationshallberecalculatedtoreferencetemperatureconditions.
Temperaturecouldalsoaffectsolidparticlemeasurementresultsifthetemperatureexceedsthestabilityoftheparticlesmeasuredortheratingofthesamplingequipment.
8.5Averagevalues
Dependingonthereproducibilityofthemethod,themeasurementfacilityandtheexperienceofthepartiesinvolvedintheprovisionofthemeasurementfacility,theaverageofseveralconsecutivemeasurementsatthesamplepointshallbeused.
Theaveragesolidparticlesmassconcentrationcpinmilligramspercubicmetreshallbedeterminedbythe
resultsofnolessthanthreemeasurementsusingtheformula:
(3)
c=
p
cp1t1+cp2t2+...+cpntn
t1+t2+...+tn
where
cp1,cp2,…,cpn
t1,t2,…,tn
arethesolidparticlecontentintheairsamples,inmilligramspercubicmetre;
arethesamplingtimes,inminutes.
9Uncertainty
Theuncertaintyofthemethoddependsontheequipmentusedandtheaccuracyoftheresultcalculation.Thetotaluncertaintyoftheauthorizedresultsofthetestshallbe±10%.
7
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BSISO8573?8:2004
10Testreport
10.1Statements
StatementsofthesolidparticlemassconcentrationandthemaximumsolidparticlediameterinthecompressedairshallbemadesuchthatthevaluescanbeverifiedinaccordancewiththeproceduresofthispartofISO8573.
Theinfluenceofanyfactors—e.g.oilcontaminantsorsamplepipe—presentinthesamplethatcouldaffecttheresultofparticleconcentrationmeasurementshallberecorded.
10.2Statementformat
ThetestreportusedtodeclaresolidparticlemassconcentrationaccordingtothispartofISO8573shallcontainthefollowing:
a)Adescriptionofthecompressedairsystemanditsworkingconditions,withsufficientdetailforthedeterminationofthevalidityofthedeclaredmassconcentrationvalue:
1)volumeflowrate;
2)samplingtime;
3)pressure;
4)temperature;
5)othercontaminants(includingwaterandoil).
b)Adescriptionofthesamplingpointwherethesamplesweretaken.
c)Adescriptionofthesamplingandmeasurementsystemused,inparticularthematerialsandequipmentused,anddetailsofitscalibrationrecord.
d)Thephrase“DeclaredsolidparticlemassconcentrationinaccordancewithISO8573-8”,followedby
1)thefigurefortheactual,averagemeasuredvalueevaluatedinaccordancewithClause8andcalculatedtorefertothereferenceconditions;
2)thefigurefortheactual,averagemeasuredvalueevaluatedinaccordancewithClause8,referringtotheactualconditions;
3)thesolidparticleconcentration,expressedinmilligramspercubicmetreatactualandreferenceconditions;
4)thepressureandtemperaturetowhichthemeasurementrefers;
5)thefigurefollowedbyastatementregardingtheapplicableuncertainty;and
6)thedateofthecalibrationrecord.
e)Thedateofthesamplingandmeasurements.
AsampletestreportispresentedinAnnexA.
8
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BSISO8573?8:2004
AnnexA
(informative)
Sampletestreport
Contentofsolidparticlesincompressedairbymassconcentration
Generaldescriptionofcompressedairsystem,testcondition,samplepoint:
____________________________________________________________________________________________
Testmethodapplied:
Samplingmethodapplied:
Listoftestequipmentusedandrespectivecalibrationdates:
____________________________________________________________________________________________
TestresultsofsolidparticlesmassconcentrationinaccordancewithISO8573-8
Test
No.
Testdateandtime
Compressedairparameters
Maximum
solid
particles
diameter
μm
Solidparticlesmassconcentration
mg/m3
Temperature
°C
Pressure
bar(e)
Totalsamplevolume
m3
Actual
condition
Referencecondition
1
2
3
...
...
...
...
Averagevalue:
Reportedby:
Date:
Authorizedby:
Date:
Ifthemeasurementisoutsideaparticularrange,thenidentifyasbeing“notmeasured”.
blank
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BSISO
8573-8:2004
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