Service manual

23
Service Information
Inhalation Toxicity
HFC-134aposesnoacuteorchronichazard
whenitishandledinaccordancewithDuPont
recommendationsandwhenexposuresare
maintainedatorbelowtheDuPontAcceptable
ExposureLimit(AEL)of1,000ppm(8and12hour
Time-WeightedAverageorTWA).
AnAELisanairborneexposurelimitestablished
byDuPontscientiststhatspeciestime-weighted
average(TWA)airborneconcentrationstowhich
nearlyallworkersmayberepeatedlyexposed
withoutadverseeffects.TheAELforHFC-134a
hasthesamevalueastheThresholdLimitValues
(TLVs)establishedforCFC-12andHCFC-22.TLVs
areestablishedbytheAmericanConferenceof
GovernmentalandIndustrialHygienists(ACGIH).
However,inhalinghighconcentrationsofHFC-
134avapormaycausetemporarycentralnervous
systemdepressionwithnarcosis,lethargyand
anestheticeffects.Othereffectsthatmayoccur
includedizziness,afeelingofintoxicationanda
lossofcoordination.Continuedbreathingofhigh
concentrationsofHFC-134avaporsmayproduce
cardiacirregularities(cardiacsensitization),
unconsciousness,andwithgrossoverexposure,
death.Intentionalmisuseordeliberateinhalationof
HFC-134amaycausedeathwithoutwarning.This
practiceisextremely dangerous.
Ifyouexperienceanyoftheinitialsymptoms,move
tofreshairandseekmedicalattention.
Cardiac Sensitization
Ifvaporsareinhaledataconcentrationof75,000
ppm,whichiswellabovetheAEL,theheartmay
becomesensitizedtoadrenaline,leadingtocardiac
irregularitiesand,possibly,tocardiacarrest.The
likelihoodofthesecardiacproblemsincreasesif
youareunderphysicaloremotionalstress.
Medicalattentionmustbegivenimmediatelyif
exposedtohighconcentrationsofHFC-134a.
DO NOTtreatwithadrenaline(epinephrine)or
similardrugs.Thesedrugsmayincreasetherisk
ofcardiacarrhythmiasandcardiacarrest.Ifthe
personishavingdifcultybreathing,administer
oxygen.Ifbreathinghasstopped,givearticial
respiration.
Spills or Leaks
Ifalargereleaseofvaporoccurs,suchasfrom
alargespillorleak,thevaporsmayconcentrate
neartheoororlowspotsanddisplacetheoxygen
availableforbreathing,causingsuffocation.
Evacuateeveryoneuntiltheareahasbeen
ventilated.Useblowersorfanstocirculatethe
airatoorlevel.DONOTreentertheaffected
areaunlessyouareequippedwithaself-
containedbreathingapparatusorunlessan
areamonitorindicatesthattheconcentrationof
HFC-134avaporsintheareaisbelowtheAEL.
Alwaysuseself-containedbreathingapparatusor
anair-linemaskwhenenteringtanksorotherareas
wherevaporsmightexist.Usethebuddysystem
andalifeline.RefertotheMaterialSafetyData
Sheet(MSDS)forHFC-134aformoreinformation.
HFC-134avaporshaveaslightlysweetodorthat
canbedifculttodetect.Therefore,frequentleak
checksandtheinstallationofpermanentarea
monitorsmaybenecessaryinenclosedspaces.
RefertoASHRAEStandards15and34for
refrigerationmachineryrooms.
ToensuresafetywhenworkingwithHFC-134ain
enclosedareas:
1.  Routereliefandpurgeventpiping(ifpresent)
outdoors,awayfromairintakes.
2.  Makecertainareaiswellventilated,using
auxiliaryventilation,ifnecessary,tomove
vapors.
3.  Makesureareaisclearofvaporspriorto 
beginningwork.
4.  Installairmonitoringequipmenttodetect
leaks.
Skin and Eye Contact
Atroomtemperature,HFC-134avaporshave
littleornoeffectontheskinoreyes.However,in
liquidform,HFC-134acanfreezeskinoreyeson
contact,causingfrostbite.Followingcontact,soak
theexposedareainlukewarmwater,notcoldor
hot.Ifmedicaltreatmentcannotbeginimmediately,
applyalightcoatofanonmedicatedointment,
suchaspetroleumjelly.Iftheexposedareaisina
locationwherethepresenceoftheointmentwould
beawkward,suchasontheeye,applyalight
bandage.Inallcasesoffrostbite,seekmedical
attentionassoonaspossible.