Particulatecontamination
Attention:Airborneparticulates(includingmetalflakesorparticles)andreactivegasesactingaloneorin
combinationwithotherenvironmentalfactorssuchashumidityortemperaturemightposearisktothe
devicethatisdescribedinthisdocument.
Risksthatareposedbythepresenceofexcessiveparticulatelevelsorconcentrationsofharmfulgases
includedamagethatmightcausethedevicetomalfunctionorceasefunctioningaltogether.This
specificationsetsforthlimitsforparticulatesandgasesthatareintendedtoavoidsuchdamage.Thelimits
mustnotbeviewedorusedasdefinitivelimits,becausenumerousotherfactors,suchastemperature
ormoisturecontentoftheair,caninfluencetheimpactofparticulatesorenvironmentalcorrosivesand
gaseouscontaminanttransfer.Intheabsenceofspecificlimitsthataresetforthinthisdocument,youmust
implementpracticesthatmaintainparticulateandgaslevelsthatareconsistentwiththeprotectionofhuman
healthandsafety.IfLenovodeterminesthatthelevelsofparticulatesorgasesinyourenvironmenthave
causeddamagetothedevice,Lenovomayconditionprovisionofrepairorreplacementofdevicesor
partsonimplementationofappropriateremedialmeasurestomitigatesuchenvironmentalcontamination.
Implementationofsuchremedialmeasuresisacustomerresponsibility.
Table21.Limitsforparticulatesandgases
ContaminantLimits
Particulate
•Theroomairmustbecontinuouslyfilteredwith40%atmosphericdustspotefficiency(MERV
9)accordingtoASHRAEStandard52.2
1
.
•Airthatentersadatacentermustbefilteredto99.97%efficiencyorgreater,using
high-efficiencyparticulateair(HEPA)filtersthatmeetMIL-STD-282.
•Thedeliquescentrelativehumidityoftheparticulatecontaminationmustbemorethan60%
2
.
•Theroommustbefreeofconductivecontaminationsuchaszincwhiskers.
Gaseous•Copper:ClassG1asperANSI/ISA71.04-1985
3
•Silver:Corrosionrateoflessthan300Åin30days
1
ASHRAE52.2-2008-MethodofTestingGeneralVentilationAir-CleaningDevicesforRemovalEfficiencyby
ParticleSize.Atlanta:AmericanSocietyofHeating,RefrigeratingandAir-ConditioningEngineers,Inc.
2
Thedeliquescentrelativehumidityofparticulatecontaminationistherelativehumidityatwhichthedustabsorbs
enoughwatertobecomewetandpromoteionicconduction.
3
ANSI/ISA-71.04-1985.Environmentalconditionsforprocessmeasurementandcontrolsystems:Airborne
contaminants.InstrumentSocietyofAmerica,ResearchTrianglePark,NorthCarolina,U.S.A.
Telecommunicationregulatorystatement
Thisproductmaynotbecertifiedinyourcountryforconnectionbyanymeanswhatsoevertointerfacesof
publictelecommunicationsnetworks.Furthercertificationmayberequiredbylawpriortomakinganysuch
connection.ContactaLenovorepresentativeorresellerforanyquestions.
AppendixD.Notices177