1、PUBLISHED DOCUMENT PD CR 12471:2002 Screening tests for nickel release from alloys and coatings in items that come into direct and prolonged contact with the skin ICS 39.060 PD CR 12471:2002 This Published Document, having been prepared under the direction of the Materials and Chemicals Sector Polic
2、y and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 30 September 2002 BSI 30 September 2002 ISBN 0 580 40486 2 National foreword This Published Document is the official English language version of CR 12471:2002. The UK participation in its pr
3、eparation was entrusted to Technical Committee STI/53, Jewellery, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred
4、 to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. aid enquirers to understand the text; present to the responsible interna
5、tional/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the CR tit
6、le page, pages 2 to 10, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsCENREPORT RAPPORTCEN CENBERICHT CR12471 August2002 ICS39.060 Englishversion Screenin
7、gtestsfornickelreleasefromalloysandcoatingsin itemsthatcomeintodirectandprolongedcontactwiththeskin Mthodedetripourlalibrationdunickeldesalliageset revtementsprsentssurlesarticlesdeconsommation entrantencontactdirectetprolongaveclapeau SchnelltestfrdieNickelabgabeausLegierungenund AuflagenaufGegenst
8、nden,diemitderHautindirekteund lngerandauerndeBerhrungkommen ThisCENReportwasapprovedbyCENon13April2002.IthasbeendrawnupbytheTechnicalCommitteeCEN/TC283. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Mal
9、ta,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2002CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMem
10、bers. Ref.No.CR12471:2002ECR12471:2002(E) 2 Contents page Foreword3 Introduction .4 1 Scope 5 2 Shortdescriptionofthemethods 5 3 Reagents.5 4 Equipment.5 5 Procedure .6 5.1 Preparationofsolutions 6 5.2 Samplepreparation .6 5.3 Testmethods 7 6 Interpretationofresults. 8 6.1 Positiveresult. 8 6.2 Nega
11、tiveresult . 9 6.3 Uncertainresult 9 7 Testreport . .9 Bibliography 10CR12471:2002(E) 3 Foreword Thisdocument(CR12471:2002)hasbeenpreparedbyTechnicalCommitteeCEN/TC283“Preciousmetals Applicationsinjewelleryandassociatedproducts“,thesecretariatofwhichisheldbyUNI.CR12471:2002(E) 4 Introduction Thisdoc
12、umenthasbeendevelopedasasimple,quickandinexpensivemeansforqualitativelytestingfornickel releasefrom(mainly)consumeritems.Ithasparticularrelevanceinrelationtoallergiccontactdermatitisdueto nickelallergy.Thetestsdescribedarequickandeasytoconductandtwoofthemaresuitableforapplication outsideofthelaborat
13、ory. EuropeanParliamentandCouncilDirective94/27/EC(OJNo.L188of22.7.94)hassetanickelreleaserate thresholdof0,5g/cm 2 /week.Althoughthepresentdocumentwillgiveinformationconcerningnickelrelease, resultsobtainedfromitsapplicationdonotconstituteconfirmationorotherwiseofcompliancewiththedirective.In order
14、toshowcompliancewiththedirective,itisnecessarythatitemsaretestedinaccordancewithEuropean StandardsEN1810,EN1811orEN12472,asappropriate,dependinguponthenatureoftheitemtobetested.CR12471:2002(E) 5 1Scope Thisdocumentpresentsascreeningprocedure,basedprimarilyontheuseofdimethylglyoxime,forthedetection o
15、fnickelreleasefromitemsthatcomeintodirectandprolongedcontactwiththeskin. Thetestsprovidequalitative,notquantitative,results. NOTEEN1811specifiesaquantitativereferencetestforthereleaseofnickel. 2 Shortdescriptionofthemethods Thetestmethodsarebasedontheformationofacolouredcomplexwhennickelionscomeinto
16、contactwith dimethylglyoximeordithiooxamide.Inordertoincreasethesensitivityofthemethod,pretreatmentwithartificial sweatandheatisusedtoinducecorrosionofthesurface,simulatingtheinfluenceofsweatwhentheitemisin contactwiththeskin.Thisscreeningmethodgivesaresultinashorttime.Theresultisindicativeandprovid
17、es guidancewhenevaluatingitemsfornickelrelease. 3Reagents Allreagentsshallbeof proanalysi gradeorbetter. 3.1 Deionizedwater 3.2 Ammoniasolution,about10%(m/m)NH 3 NOTEThissolutionmaybepreparedfromamoreconcentratedammoniasolution;forexample,onecontaining24%or30% (m/m)NH 3. 3.3 Sodiumchloride , NaCI 3.
18、4 Lacticacid,CH 3 CHOHCOOH, r =1,21g/ml,88% 3.5 Urea,CO(NH 2 ) 2 3.6 Dimethylglyoxime,C 4 H 8 N 2 O 2 ,99%,orteststripsforthedetectionofnickel,containingdimethylglyoximeor othercolorimetricreagent(s)withapproximatelyequivalentselectivityandsensitivitytonickel. 3.7 Ethanol,C 2 H 5 OH, 95% 3.8 Hydroge
19、nperoxide,H 2 0 2 ,approximately30%(m/V)solution(100volume).(Notrequiredforthepretest, 5.3.4orthefieldtest,5.3.6) 3.9 Dithiooxamide(rubeanicacid),C 2 H 4 N 2 S 2 .(Notrequiredforthepretestorthefieldtest) 3.10 Sodiumacetatetrihydrate,C 2 H 3 NaO 2 3H 2 O.(Notrequiredforthepretestorthefieldtest) 3.11
20、Aceticacid,glacial,C 2 H 4 O 2 .(Notrequiredforthepretestorthefieldtest) 4Equipment 4.1 Flatbottomeddish,madeofglassorothernonmetallicmaterial.(Notrequiredforthepretest) 4.2 Thermometer,(0C100C)1CCR12471:2002(E) 6 4.3 Pasteurpipetteor,forthefieldtest,adropdispensingbottlecapableofdispensingdropswith
21、an approximatevolumeof50I. 4.4 Cottonwooltippedsticks(white) 4.5 pHmeterornarrowrangepHpaper 4.6 Laboratoryoven,capableofmaintainingatemperatureof50C3C(requiredforthelaboratorytest,5.3.5) 4.7 Heating/dryingapparatus(requiredonlyforthefieldtest) 4.7.1 Handheldhairdryer, or 4.7.2 Apparatusconsistingof
22、alightbulb,reflectortype,(IEC887:R80;60Wto100W)mountedvertically downwardsinalampholderpositionedaboveaflatbase,suchthatthedistanceofthefaceofthebulbabovethe flatbasemaybevariedbetweenapproximately40mmand120mm. 5Procedure 5.1Preparationofsolutions Unlessotherwisespecified,thefollowingsolutionsaresta
23、blefor6monthsattemperaturesbelow25C. 5.1.1 Dimethylglyoxime,0,8%(m/V)alcoholicsolution.Weigh0,8g0,05gofdimethylglyoxime(3.6),dissolve andmakeupto100mlinethanol(3.7). 5.1.2 Artificialsweat.Transfer1g0,02gurea(3.5),5g0,1gsodiumchloride(3.3)and1,13g0,02g(940 l20l)lacticacid(3.4)intoa2litrebeaker.Add100
24、0mldeionizedwater(3.1)andstir.UsingapHmeteror pHpaper(4.5),adjustthepHto6,50,2bythedropwiseadditionofammoniasolution(3.2)withstirring.Artificial sweatisstablefor6monthswhenkeptinthedarkbelow8Cinaclosedcontainer. NOTETheuseofapHmeterispreferabletotheuseofnarrowrangepHpaper. 5.1.3 Dithiooxamide,0,5%(m
25、/V)alcoholicsolution.Weigh0,5g0,05gofdithiooxamide(3.9),dissolveand makeupto100mlinethanol(3.7). 5.1.4 Sodiumacetatebuffersolution,pH4.5.Weigh5,6gsodiumacetatetrihydrate(3.10)andadd2,4mlglacial aceticacid(3.11).Dissolveandmakeupto10mlwithwater. 5.2Samplepreparation 5.2.1 Thesurfacestobetestedarethos
26、ethatcomeintodirectandprolongedcontactwiththeskin.The surface(s)oftheitemtobetestedshallbecleanedwithethanol(3.7)usingacottonwooltippedstick(4.4). NOTE1Thiscleaningstageisintendedtoremoveextraneousgreaseandskinsecretionsduetohandling,butnotany protectivecoatings.However,itwillalsosubstantiallyremove
27、anynickelsaltspresentonthesurfaceofthetestitem.If thereis arequirementtodetectthepresenceofsurfacecontaminationbynickel,thiscleaningstageshouldbeomitted. NOTE2Anitemmaybecomposedofpartsmadeofdifferentmaterials,eachofwhichmayrequiretestingiftheycomeinto directandprolongedcontactwiththeskin. NOTE3Cont
28、aminationbyobjectscontainingnickel(paperclips,rivets,coins,etc.)maygivefalsepositiveresultsifsuch objectscomeintocontactwithtestitems,surfaces,reagentsorthehands.Thispossibilityshouldbeeliminatedbyavoidance of nickelcontainingobjects,washingthehandsbeforeperformingthetestsandperformingblanktests.CR1
29、2471:2002(E) 7 5.2.2 Thepresenceofcoatings,suchaspaint,lacquerandelectroplate,canpreventthedetectionofanickel releasingsubstrate.Therefore,abrasionofthesurfacepriortotestingfornickelreleaseshouldbeconsidered, especiallyifanegativeresult(see6.2)hasbeenobtainedontheunabradeditem.Thismaybeachievedusing
30、 emerypaper,emeryboardorothernickelfreeabrasivematerial. CAUTIONThisprocedureislikelytodamagetheitem. NOTEIfapositiveresultisobtainedinthesecircumstances,testinginaccordancewithEN12472isrequiredtocheck compliancewithEUDirective94/27/EC. 5.3Testmethods 5.3.1 Thepersoncarryingoutthetestsshallhaveanorm
31、alcolourvisioninregardtobeingabletodetectredand pinkcolours. 5.3.2 Checkthereactivityofthetestsolutions,asnecessary,byapplyingthetesttoaknownnickelreleasing surface,e.g.acupronickelcoin. 5.3.3 Eitherconductthepretest(5.3.4)and/orthelaboratorytest(5.3.5)orthefieldtest(5.3.6). a) Ifthepretestisconduct
32、edandapositiveresult(redcolouration)isobserved,furthertestingisunnecessary unlessthepresenceofironissuspected(see5.3.8); b) Ifthepretestisconductedandanegativeresult(absenceofredcolouration)isobserved,conductthe laboratorytest(5.3.5)orthefieldtest(5.3.6). NOTEThepretestonlygivesapositiveresultinthep
33、resenceofnickelsaltsorwherenickelisavailableforreleasefrom an itemwithoutpriorcorrosion(seeclause2). 5.3.4 Pretestfornickelrelease:moistenacottonwooltippedstick(4.4)withoneortwodropsof dimethylglyoximesolution(5.1.1)andonedropofammoniasolution(3.2).Checkthatthereisnodiscolouration. Rubfirmlythecotto
34、nwooltipfor15sagainstthesurfacetobetested.Viewthestickagainstawhitebackground. Theappearanceofaredcolour,fromlightpinktostrongcerise,indicatesnickelrelease. 5.3.5 Laboratorytest:placethetestitemonadish(4.1)andpreheatittoapproximately50C.UsingaPasteur pipette,transferonedropofartificialsweat(5.1.2)on
35、tothesurfacetobetested.Drytheiteminthelaboratory oven(4.6)untilitssurfaceiscompletelydry.Thetemperatureshallbe50C3C.Dryingtimewillbeabout15 min.Performthetestfornickelrelease(5.3.7,5.3.8or5.3.9,asappropriate). 5.3.6 Fieldtest:placethetestitemonadish(4.1)andusingaPasteurpipetteoradropdispensingbottle
36、4.3) putonedropofartificialsweat(5.1.2)onthesurfacetobetested.Drythesurfacecompletelywiththehairdryer (4.7.1).Ifnecessary,keeptheiteminplaceusinganysuitablemeans.Placeathermometer(4.2)closetothetest item.Thetemperatureshallnotexceed50C. Alternatively,thetestitemcanbedriedbytheheatfromanelectricligh
37、tbulbusingtheequipmentdescribedin 4.7.2.Thelightbulbisswitchedonandallowedtowarmup.RaiseorIowerthelampholdertoobtainaconstant temperatureofapproximately50Cjustabovethesurfaceontheflatbasedirectlybeneaththelamp.Placethe testitemonadishdirectlybeneaththecentreofthelamp.Preheattheitemforabout10minthenp
38、utonedropof artificialsweatonthesurfacetobetested.Allowthesurfacetodrycompletely. Performthetestfornickelrelease(5.3.7).CR12471:2002(E) 8 5.3.7 Testingfornickelrelease:allowtheitemtocoolforapproximately5min.Moistenacottonwooltipped stick(4.4)withoneortwodropsofdimethylglyoximesolution(5.1.1)andonedr
39、opofammoniasolution(3.2). Checkthatthereisnodiscolouration.Placethetipofthecottonwooltippedstickontotheareatobetestedand rubgentlyfor5s.Viewthestickagainstawhitebackground.Theappearanceofaredcolour,fromlightpinkto strongcerise,indicatesnickelrelease. Usingteststripsforthedetectionofnickel:Allowtheit
40、emtocoolandimmediatelyputonedropofammonia solution(3.2)onthedriedsalts.Placetheteststrip(3.6)ontothetreatedareafor5s.Viewthestripagainsta whitebackground.Theappearanceofaredcolour,fromlightpinktostrongcerise,indicatesnickelrelease. NoteDuetothecorrosioninducedbytheartificialsweatandformationofsaltso
41、nthesurface,shortertimeandpressureis neededforthetestingin5.3.7thanwhenperformingthepretest(5.3.4). 5.3.8 Checkingforinterferencebyiron(laboratorytestonly):whenstainlesssteelorotherironcontainingitems aretested,ferrousionscancausearedorreddishbrowncolouration.Thiscolourationcaninterferewiththe detec
42、tionofnickel.Inordertoeliminatetheinfluenceofiron,thetest(5.3.7)shouldbemodifiedinthefollowing way.Afterallowingthetestitemtocoolforapproximately5min,moistenthetipofacottonwooltippedstick(4.4) withoneortwodropsofdimethylglyoximesolution(5.1.1)andonedropofammoniasolution(3.2).Placeadropof hydrogenperoxidesolution(3.8)ontothesurfacetobetested.Thisoxidisesferrousions(Fe 2+ )toferricions(Fe 3+ ). Rubthetestareagentlywiththecottonwooltipfor5s.Viewthestickagainstawhitebackground.Theappearance ofareddishcolourindicatesnickelrelease.Theappearanceofotherco
