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LicensedCopy:LondonSouthBankUniversity,LondonSouthBankUniversity,FriDec2217:28:23GMT+00:002006,UncontrolledCopy,(c)BSI

BRITISHSTANDARD

Compressedair—

Part8:Testmethodsforsolidparticlecontentbymassconcentration

ICS71.100.20

NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAW

BSISO

8573-8:2004

Britishstandards

BSISO8573-8:2004

LicensedCopy:LondonSouthBankUniversity,LondonSouthBankUniversity,FriDec2217:28:23GMT+00:002006,UncontrolledCopy,(c)BSI

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

4

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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.

6

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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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