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Evaluation of Histoplasmosis Concerns at a United States Post Office
Lilia Chen, MS
Ayodele Adebayo, MD, MPH
National Institute for Occupational Safety and Health
Health Hazard Evaluation Report HETA 2007-0216-3056 United States Postal Services Apply Valley, California Febuary 2008
DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention
Workplace Safety and Health
The employer shall post a copy of this report for a period of 30 calendar days at or near the workplace(s) of affected employees. The employer shall take steps to insure that the posted determinations are not altered, defaced, or covered by other material during such period. [37 FR 23640, November 7, 1972, as amended at 45 FR 2653, January 14, 1980].
Contents
RepoRt Abbreviations........................................................................ ii
Highlights.of.the.NIOSH.Health.Hazard.Evaluation............. iii
Summary............................................................................. iv
Introduction...........................................................................1
Assessment..........................................................................3
Results.and.Discussion........................................................4
Conclusions........................................................................10
Recommendations..............................................................10
References.........................................................................13
Appendix A Health.Effects.....................................................................16
Appendix B Additional.Information.on.IEQ.Issues.................................17
ACknowledgments Acknowledgements.and.Availability.of.Report....................19
Health Hazard Evaluation Report 2007-0216-3056 Page �
ABBReviAtions
ANSI AmericanNationalStandardsInstitute
APWU AmericanPostalWorkersUnion
ASHRAE AmericanSocietyofHeating,RefrigeratingandAirConditioningEngineers
AVPO AppleValleyPostOffice
cfm Cubicfeetperminute
CO Carbonmonoxide
CO2 Carbondioxide
EPA EnvironmentalProtectionAgency
ft2 Feetsquared
H. capsulatum Histoplasmacapsulatum
HEPA High-efficiencyparticulateair
HHE Healthhazardevaluation
HIV Humanimmunodeficiencyvirus
HVAC Heating,ventilating,andair-conditioning
IEQ Indoorenvironmentalquality
m3 Cubicmeter
MSDS Materialsafetydatasheet
NALC NationalAssociationofLetterCarriers
NIOSH NationalInstituteforOccupationalSafetyandHealth
PPE Personalprotectiveequipment
ppm Partspermillion
RH Relativehumidity
USPS UnitedStatesPostalService
Page �� Health Hazard Evaluation Report 2007-0216-3056
HigHligHts of tHe
niosH HeAltH
HAzARd evAluAtion
Health (NIOSH) received
(HHE) at the United
and air conditioning
2007.
The National Institute for Occupational Safety and
a union request for a health hazard evaluation
States Postal Service Office in Apple Valley, California. The request concerned workers at the post office potentially being exposed to pigeon droppings from pigeons roosting in the building’s heating, ventilating,
(HVAC) units. NIOSH investigators conducted an investigation in July
What NIOSH Did ● Weperformedconfidentialmedicalinterviewswithemployees
regardingtheirhealthsymptoms.
● Weinspectedthebuilding’sventilationsystemandreviewedthe system’sdesign.
● Wetookindoorenvironmentalqualitymeasurements (temperature,relativehumidity,andcarbondioxide[CO2
]).
● Wereviewedthebuildingventilationschematics,relevant healthandsafetyrecords,andpastsamplingreports.
What NIOSH Found ● Wefoundnospecificoccupationalorenvironmentalexposure
thatexplainsthehealthsymptomsthepostofficeemployees reported.
● Wefoundthatcomfortparametersatthepostofficewere withinacceptableguidelinesexceptforelevatedCO2
levels measuredinsomeworkareas,possiblyindicatinginadequate outdoorairintakeorunevenmixingofair.
● WefoundthattherooftopHVACunitshadbirdnettingin placetopreventpigeonentry.
● Wefoundnoevidenceofbirdsoranyotheranimalsinthe HVACunits.
What Managers Can Do ● Managersshouldmaintainnettingprotectionaroundthe
HVACunitstokeepbirdsout.
● Managersshouldensurethatoutdoorairdampersarenot completelyclosedtoallowadequateoutdoorairintake.
● Managersshouldensurethatregularhousekeepingactivities areperformedonaregularbasistoreducetheamountof particulatematterinthebuilding.
● Managersshouldhaveatestandbalanceoftheventilation systemdonetodeterminewhethertheHVACsystemis performingasdesigned.
What Employees Can Do ● Employeesshouldpromptlyreportanyconcernstheyhave
regardingbuildingconditionstomanagement.
● Employeesshouldtalkwiththeirphysiciansregardingany symptomstheybelievetobework-related.
Health Hazard Evaluation Report 2007-0216-3056 Page ���
summARy
The symptoms reported by employees can be caused by a variety of health conditions and illnesses and could not be attributed to a specific workplace exposure. After inspecting the
medical interviews, and taking into account the environmental requirements of H. capsulatum spores, we deemed that the potential for employees to contract histoplasmosis was
we do not recommend general testing for all
employees with persistent symptoms should contact their physician on a case-by-case basis to determine if individual testing is appropriate.
HVAC units, performing
very low. Therefore,
AVPO employees for histoplasmosis. However,
OnApril17,2007,NIOSHreceivedarequestfromNALCforan HHEonbehalfofworkersattheUSPSinAppleValley,California. NALCrepresentativesfiledtheHHErequestbecauseworkers atthepostofficewerepotentiallyexposedtopigeondroppings frompigeonsroostingontheroofandinthebuilding’sHVAC units.Someworkersreportedexperiencingdizziness,breathing difficulties,cough,andweakness,andwereconcernedthatthese symptomsresultedfromexposuretoH. capsulatum,afungusthat causeshistoplasmosis,afungallunginfection.Adead-animal odorinthebuildingwasreportedbyemployeesandadded totheirconcerns.TheNALCspecificallyaskedthatNIOSH conductorrecommendmedicaltestingforallAVPOemployeesto determinewhetherthesesymptomswererelatedtoexposuretoH. capsulatum,andconductanyadditionalsiteevaluationsdeemed necessarytoensurethehealthandsafetyofthepostalworkers.
OnJuly11-13,2007,NIOSHrepresentativesmadeasitevisit totheAVPO.NIOSHinvestigatorsheldopeningandclosing conferenceswithunionrepresentatives(NALC),managementof AVPO,thesafetymanager,representativesfromtheUSPSSan Diegodistrictoffice,andanindustrialhygienecontractorwho previouslyperformedenvironmentalsampling.WetookIEQ measurements(temperature,RH,andCO2
)andheldconfidential medicalinterviewswithUSPSemployees.Wealsoreviewed availableenvironmentaltestingreportsandmaintenancerecords.
Wefoundnodirectrelationshipbetweencurrenthealthsymptoms reportedbyAVPOemployeesandspecificoccupationalor environmentalexposures.Perceivedodorandbuildingventilation issueslikelycontributedtothesesymptoms.Wefoundthatthe potentialforemployeestocontracthistoplasmosiswaslowandthis potentialwasfurtherminimizedbycleaningandinstallingnets aroundtheHVACunits.WedonotrecommendtestingAVPO employeesforhistoplasmosis.However,ifindividualemployees feelthattheyshouldbetestedduetotheirsymptoms,theyshould discusstheirsymptomsandconcernswiththeirphysician.
Atthetimeofourinvestigation,wefoundcomfortparametersat thepostofficetobewithinacceptableguidelinesrecommended byASHRAEexceptforelevatedCO2
levelsinsomeworkareas, possiblyindicatinginadequateoutdoorairintakeorunevenmixing ofair.Allpigeonfecalmatterhadbeenclearedfromtheunitswe
Page �v Health Hazard Evaluation Report 2007-0216-3056
summARy (Continued) examinedand,overall,thebirdnettingappearedintact.Although wesawtwobirdfeathersinoneoftheHVACunits,wefoundno evidencethatbirdswereenteringorstilllivingintheunit.
Keywords: NAICS 491110 (Postal Service), histoplasmosis, pigeons, fecal matter, postal workers, indoor environmental quality, IEQ, ventilation, odors
Health Hazard Evaluation Report 2007-0216-3056 Page v
Thispageintentionallyleftblank.
intRoduCtionOnApril17,2007,NIOSHreceivedarequestfromtheNALC foranHHEonbehalfofworkersattheUSPSinAppleValley, California.NALCrepresentativesfiledtheHHErequestbecause workersatthepostofficewereconcernedaboutpigeondroppings frompigeonsroostingontheroofandinthebuilding’sHVAC units.Workersreportedexperiencingdizziness,breathing difficulties,cough,andweakness,andwereconcernedthatthese symptomsresultedfromexposuretoH. capsulatum,afungusthat causeshistoplasmosis,afungallunginfection.Adead-animalodor inthebuildingwasreportedbyemployeesandaddedtotheir concerns.TheNALCspecificallyaskedthatNIOSHconductor recommendmedicaltestingforallAVPOemployeestodetermine whetherthesesymptomswererelatedtoexposuretoH. capsulatum, andconductanyadditionalsiteevaluationsdeemednecessaryto ensurethehealthandsafetyofthepostalworkers.
TheAVPOislocatedinthedesertabout2hourseastofLos AngelesinSanBernardinoCounty.Thebuildingisaone-story 28,000ft2warehouse-likestructurebuiltin1988.AVPOemploys 96employees,67ofwhomarelettercarriersand29ofwhomare clerks,custodians,orsupervisors.Customerpostboxesandmail servicesarelocatedatthefrontofthebuilding.Thebackofthe buildinghousesthedistributioncenter,whereclerksandletter carrierssortincomingmail,andtruckdriverspickupoutgoing mail.
Typically,mailclerksstarttheirshiftat3:30a.m.andseparate incomingmailbyroutesforthelettercarriers.Lettercarriers begintheirshiftsat8:00a.m.andsortthemailfortheirroutes ina“case,”whichisathree-walledboothwithstanding-room onlyspace.Eachwallhasshelvesofholdingslotswheretheletter carriersorganizemail.Lettercarriersleavethebuildingtodeliver mailatapproximately10:30a.m.andreturnaround5:00p.m. Theyaverage3.5to4hoursinthebuildingand5or6hours ontheirroutes.Somelettercarriersalsoworkovertimetoa maximumof10hoursoftotalworkperday.Clerks,custodians, andsupervisorsspendthemajorityoftheirworkinghoursinthe building.
Managementreportedthatfacilitymaintenanceemployees dusthighareasonaquarterlybasis.However,theydonotkeep recordsofwhodusted,orwhen.TheAVPOusesanindependent contractorforpestcontrol,whosetstrapsandspraysforpests quarterly.
Health Hazard Evaluation Report 2007-0216-3056 Page �
intRoduCtion (Continued) AVPOemployeesarerepresentedbytwounions,theNALCand theAPWU.LettercarriersarerepresentedbytheNALC,and custodiansandclerksarerepresentedbytheAPWU.Complaints orconcernsofsafetyissuescanbebroughttotheattentionof theunionchiefstewards,whonotifymanagement;alternatively, employeescanfilloutaReportofHazard,UnsafeCondition orPractice(1767)formthattheymayanonymouslysubmitto management.Managementisrequiredtorespondtotheemployee onthecorrectiveactiontaken,eitherdirectlyorthroughameeting ofallemployees(inthecaseofanonymoussubmittal)withinthe sameworktour.
TheAVPOhasaSafetyandHealthCommitteecomposedof volunteeremployeesandmanagement.Managementandunion representativeshavestatedthattheyhavemissedsomemeetings andwouldliketoresumeregularcommitteemeetingsand activities.
InJanuary2006,agroupofAVPOemployeesperceivedadead-animalodorinandimmediatelyoutsidethebuilding.Thisodor wasreportedlyassociatedwithsymptomssuchasnausea,dizziness, headaches,light-headedness,cough,andbreathingdifficulty.Upon findingthatpigeonshadbeenlivingandnestingintherooftop HVACunits,managementprocuredaproposalfromacleaning andsanitizingcompanytoremovethepigeondebris,deadanimals, andnestingmaterial,andinstallbirdnettingforalloftheHVAC units.Thisproposalwasnotapprovedbecauseitwasdeemedtoo expensivebythepriorAVPOmanagement.
OnMarch6,2006,AVPOcontractedanHVACcontractorto eliminatetheodorproblem.Thecontractorfoundevidenceof nestinginoneoftheHVACunits;inaddition,filtersontwoof theunitsneededtobechanged.Thecontractorremovedthebird debrisandreplacedthefilters.However,employeesreportedthat theodorpersisted.
OnMay11,2006,theHVACcontractorreturnedtothepostoffice toservicethesupplyunitfortheemployeebreakroom,men’s lockerroom,andbathroom;areaswheretheodorwasreportedly worst.Theyfoundandfixedabrokenventpipe,whichwas thoughttobethesourceofthesmell.Theyalsoreportedclosing theoutdoorairdamper.Theodorwasreportedlylessnoticeable overtimeafterthesechangesweremade.
Page � Health Hazard Evaluation Report 2007-0216-3056
intRoduCtion (Continued) OnSeptember28,2006,thebudgetwasapprovedtocleanand removebirddebrisandinstallbirdnettingaroundtwoHVAC unitslocatedintherecessedareaontherooftop(proposalwas submittedinJanuary2006,bytheoriginalcleaningandsanitizing company).TwooftherooftopHVACunitsarecompletelyencased withnettinginacage-likestructure.Theothersevenunitshave nettingthatisattachedtothebottomoftheunitsandweighted totheroof,preventingbirdaccessintotheunitviatheoutdoor airdampers.Managementreportedthatthecompanytook severalweekstopressure-washthearea;removenests,birdfecal material,anddebris;andinstallthenetting.Althoughthecontract agreementwereviewedspecifiednettingforonlytwooftheHVAC rooftopunits,managementstatedthatalltheunitswerenettedat thattime.
InJanuary2007,severalemployeesraisedconcernsthathealth symptomstheyhadbeenexperiencingmaybeattributedto exposuretoH. capsulatuminthebirddroppings.Inresponse toemployeeconcerns,managementhiredanindependent environmentalconsultantonMarch6,2007,whotooktwo ambientairandonebulksample(fecalmatter)totestforavian-bornepathogens(H. capsulatum, Cryptococcus neoformans,and Chlamydophila psittaci).Airsampleswerecollectedonto37-millimeterpolycarbonatefiltersusinghigh-flowvacuumpumps calibratedat10litersperminuteandanalyzedbypolymerasechain reaction.Bothairsampleswerereportedbelowthedetectionlimit of100organisms/filteror<88organisms/m3,andnopathogens weredetectedinthebulksample.
OnMay23,2007,aUSPSbuildingengineerreportedthatone oftheHVACunitswasagaininfestedwithpigeons.OnMay30, 2007,theHVACcontractorremovedfeathers,pigeondebris,and deadpigeonsfrominsidetheHVACunit.Theotherunitshad nosignsofbirdactivityorroosting.Thecontractor’sworklog indicatedthattheycleanedtheeconomizersandcoolingcoils,and resealedanypossibleareasofpigeonentry.
Assessment OnJuly11-13,2007,wemadeasitevisittotheAVPO. NIOSHinvestigatorsheldanopeningconferencewithNALC representatives,AVPOmanagement,thesafetymanager, representativesfromtheUSPSSanDiegodistrictoffice,and anindustrialhygienecontractorwhoperformedtheprevious
Health Hazard Evaluation Report 2007-0216-3056 Page �
Assessment (Continued)
Results And disCussion
environmentalsampling.Wealsodirectlyaddressedallthe employeestoinformthemofthehazardevaluationandour proposedactivities.WetookIEQmeasurements(temperature,RH, andCO2)andheldconfidentialmedicalinterviewswithUSPS workers.Inadditiontoobservingtheworkarea,wereviewedthe buildingventilationschematics,anairsamplingreport,MSDSs, workorderspertainingtotheHVACunits,andReportofHazard Logs.WeheldaclosingconferenceonthemorningofJuly13to discusspreliminaryfindingsandrecommendations.
Medical Interviews
OnJuly11and12,2007,weinterviewedthirty-sevenemployees whowereinterestedinprivateandconfidentialinterviews.All interviewedemployeesreportedperceivingadead-animalodor thatwasworseontheeastsideofthebuilding.Nineemployees reportednosymptoms.Oftheremaining28employees,13 reportedfrequentheadaches,10reportedepisodictransient dizziness,and10reportedhavingfrequentepisodesofcommon cold,flu,orbronchitis.Othersymptomsreportedweresinus problemsbynineemployees;shortnessofbreathbyseven employees;musculoskeletalcomplaintssuchasneck,back,and shoulderpainandmusclespasmbysixemployees;andfatigue byfiveemployees.Nausea,hernia,andpalpitationswereeach reportedbytwoemployees.Abouthalfofthosewithsymptoms reportednoimprovementawayfromworkincludingduring vacation.Allbuttwoemployeesnotedthattheodorsubsidedwhen theareaaroundtheHVACunitswascleanedofpigeondroppings, andsomenotedconsiderableimprovementorresolutionof theirsymptomsaftertheHVACunitswerecleaned.Someofthe employeesinterviewednotedthattheirdeliveryroutesaredirt roadsandthoughtthatsomeoftheirsymptomsmaybedueto exposuretodust.
ThesymptomsreportedatAVPOcanbecausedbyavariety ofillnessesandenvironmentalconditions.Theseconditions andillnessescouldincludetheperceptionofunpleasantodors [Dalton1999;Shusterman1992;Bruvoldetal.1983;Amesand Stratton1991],poorindoorairquality[LindgrenandNorback 2005;ErdmannandApte2004;Skyberg2003;Nagdaand Hodgson2001;CrandallandSieber1996],thecommoncold,or histoplasmosis.Becausethesymptomsarefrequentlyassociated
Page � Health Hazard Evaluation Report 2007-0216-3056
Results And disCussion (Continued) withsomanytypesofillnesses,wecannotusesymptomsaloneto
pinpointtheexactcauseoftheworkers’concerns.Instead,we usesymptomsandtheotherfactorsdescribedinthisreportto determinetheprobabilityofawork-relatedexposure.
EmployeesmayhavebeenexposedtoH. capsulatumatAVPO,but thispossibilityisverylow,andwedonotrecommendtestingofall employeesforhistoplasmosisforthefollowingreasons:
● HistoplasmosisisnotendemicorprevalentinCalifornia. TheconditionsthatfavorthegrowthofH. capsulatumin soilareameantemperatureof71°Fto84°F,anannual precipitationof35to50inches,andarelativehumidityof 67%to87%[Deepe2004;Zeidbergetal.1955].Because theprevailingclimateinAppleValleyisnotfavorablefor thegrowthofH. capsulatum,thepotentialforexposureto H. capsulatumamongAVPOemployeesisverylow.
● Althoughsomeofthesymptomsreportedbyseveral employeeshavealsobeenreportedbypersonswith histoplasmosis,theconstellationofsymptomsreporteddid notsuggestthatemployeeshadactivehistoplasmosis.
● Becauseofinherentproblemsinthevariousclinicaltests forhistoplasmosissuchasfalsepositivity(positivetestresult intheabsenceofhistoplasmainfection),falsenegativity (negativetestresultinpersonswithhistoplasmainfection), andtheinabilityofsomeoftheteststodifferentiatepast fromcurrentinfection,areasonabledegreeofpretest probability(thelikelihoodofhavinghistoplasmosis)is neededtosupportcommunitytestinginordertoovercome inherenterrorsinthesetests.
Othermedicalconditionsthathavebeenassociatedwithexposure topigeonfecalmaterialandpigeonproteinsarepsittacosis, cryptococcosis,andhypersensitivitypneumonitis.Personswith psittacosis(infectionduetoChlamydophilia psittaci)usuallyhave symptomsofhighfeverwithchills,severecough,andnon-specific symptomssuchasheadache,joint,andmuscleaches[Schlossberg 2004].Personswithpsittacosismayhavechestpainwithshortness ofbreath[Schlossberg2004].Althoughlungsymptomsmayoccur inpersonswithcryptococcosis(diseasecausedbyCryptococcus neoformans),itisuncommonandpresentsasfever,cough,chest painandmalaise.Thecommonpresentationiscryptococcal meningitis,whosesymptomsarefever,confusion,headache,neck
Health Hazard Evaluation Report 2007-0216-3056 Page �
Results And disCussion (Continued) stiffness,andinseverecases,coma[Perfect2004].Basedonour
interviewsofemployees,wedonotthinkthatemployeesofAVPO currentlyhavetheseconditionsanddonotrecommendtesting ofallemployeesforthesediseases.Employeeswithpersistent symptomsshouldconsulttheirphysicianstodetermineiftestingis appropriateonacase-by-casebasis.
Hypersensitivitypneumonitisiscausedbythebody’simmune responsetoexposuretoorganicparticles,inthiscase,pigeon proteins(antigens).Acutediseaseusuallymanifestsasfluor atypicalpneumoniaandistypicallyself-limitingifexposure ceases[Rose2005].Subacuteandchronicdiseasesmaycause progressiveshortnessofbreath,cough,malaise,fatigue,weight lossanddecreasedlungfunction[Rose2005].Ourinterviewof employeesatAVPOdidnotsuggestthatemployeescurrentlyhave hypersensitivitypneumonitis.
Thepotentialforemployeestobeexposedtothecausativeagents ofthesemedicalconditionshasbeeneliminatedasaresultofthe cleaningandthenettinginstalledaroundtherooftopHVACunits. Thepotentialforexposureshouldnotoccuraslongastheintegrity ofthenetsismaintainedandpigeonroostingiseliminated.For moreinformationonhistoplasmosis,refertoAppendixAatthe endofthisreportandtheNIOSHdocument“Histoplasmosis: Protectingworkersatrisk,”[NIOSH2004],whichcanalsobe foundathttp://www.cdc.gov/niosh/docs/2005-109/.
Facility Survey
TheAVPOhasnineHVACunitsontheroof.Untilrecently,the USPSSanBernadinomaintenanceemployeeswereresponsible forchangingairfiltersforseveraldifferentpostalofficebuildings inthearea.AVPOmanagementsaidthatthesemaintenance employeesreplacedairfiltersquarterlyattheirfacility,butdidnot keepwrittenrecordsoftheseactivities.OnMay30,2007,AVPO establishedamaintenanceagreementwithanindependentHVAC contractortomaintaintheirHVACunits,includingfouryearly preventivemaintenancecheck-ups,includingfilterchange-outs, althoughtheSanBernadinoFacilitiesDepartmentstillsupplies thereplacementairfilters.
Duringthebuildingwalk-through,weopenedandinspectedtwo oftheHVACunitsontheroofandexaminedthefilters,outdoor
Page � Health Hazard Evaluation Report 2007-0216-3056
Results And disCussion (Continued) airdampers,coolingcoils,andbirdnetting.Inoneoftheunits,
wefoundapigeonfeatherinthefrontoftheairfilterandanother featherbehindthefilteronthecoolingcoils.Giventheproper positioningofthefiltersatthetimeofinspection,thefeather shouldnothavebeeninthisarea.Wespeculatedthatthefeathers mayhavebeenleftafterthecleaningprocessorhadbeenknocked offtheairfiltersontothecoilduringfilterchange-out.Nopigeon fecalmatterwasfoundinanyoftheHVACunits,andbirdnetting lookedintactaroundalltheunits,althoughsomenettinglocated inareaswheretheunitandductworkjoinedhadsmallgapsbig enoughforapigeontoenter.Also,wefoundfreshbirddroppings neartwooftheexhaustvents.Managementsurmisedthatthe pigeonswereattractedtothewarmairexhaustingfromthosevents andiscurrentlylookingintoinstallingbirdspikestodiscourage pigeonsfromgatheringaroundthevents.
Whileinvestigatingthehistoplasmosisconcerns,NIOSH investigatorsperformedanIEQevaluationtoidentifyany potentialissuesbytakingthermalcomfortmeasurementsand lookingattheventilationsystem.Oneofthemostcommon deficienciesintheindoorenvironmentistheimproperoperation andmaintenanceofventilationsystemsandotherbuilding components[Rosenstock1996].NIOSHinvestigatorshavefound thatcorrectingHVACproblemsoftenreducesreportedsymptoms. Moststudiesofventilationratesandbuildingoccupantsymptoms haveshownthatventilationratesbelow20cubicfeetperminute perperson,areassociatedwithoneormorehealthsymptoms [Seppanenetal.1999].WhenconductinganIEQsurvey,NIOSH investigatorsoftenmeasurethermalcomfortindicators,such asCO2
,temperature,andRHtoprovideinformationrelative tothefunctioningandcontrolofHVACsystems.Maintaining theseparametersatrecommendedlevelshasoftenbeenshownto resultinresolutionorsymptomaticimprovementsinoccupants. Thus,improvedHVACoperationandmaintenance,higher ventilationrates,andcomfortabletemperatureandRHcanall potentiallyservetoimprovesymptomswithouteveridentifying anyspecificcause-effectrelationships.Wehaveincludedadditional informationonIEQparametersinAppendixB.
CO isanormalconstituentofexhaledbreathanditisnot 2
consideredabuildingairpollutant.Itisanindicatorofwhether sufficientquantitiesofoutdoorairarebeingintroducedinto anoccupiedspace.ANSIandASHRAErecommendthatthe indoorCO2
concentrationbewithin700ppmoftheoutdoor
Health Hazard Evaluation Report 2007-0216-3056 Page �
Results And disCussion (Continued) concentrationforcomfort(odor)reasons[ANSI/ASHRAE
2007].ElevatedCO2concentrationssuggestthatotherindoor
contaminantsmayalsobeincreased.IfCO2concentrationsare elevated,theamountofoutdoorairintroducedintotheventilated spacemayneedtobeincreased.ASHRAE’sventilationstandard, ANSI/ASHRAE62.1-2007:Ventilation for Acceptable Indoor Air Quality,recommendsacombinedoutdoorairrateof17cfm/ personforofficespaces,andareaoutdoorairratesof0.12cfm/ft2 forshipping/receivingareasand0.06cfm/ft2forwarehouses,as longasstoredmaterialshavenopotentiallyharmfulemissions [ANSI/ASHRAE2007].
Wemonitoredtheworkareafortemperature,RH,CO,andCO2
usingaQ-TRAKPlusIndoorAirQualityMonitor,Model8554 (TSIIncorporated,Shoreview,Minnesota).COwasmeasured becauseitisacommoncomponentofvehicleexhaust.Mail carriertrucksarelocatedinaparkinglotabout30feetfromaset ofdoubledoors.Trucksthatbringincomingmailunloadfour differenttimesataseparateloadingdockbetween3:30a.m.and 8:30a.m.andloadthreeseparatetimestoremoveoutgoingmail from1:30p.m.until6:00p.m.NoCOwasdetectedwhentrucks wereleavingorreturningfromtheirroutes.
WetookCO2measurementsonJuly11afterthebuildingwalk-
throughwhenthebuildingwasatlowoccupancy,andonthe morningofJuly12duringhighoccupancy.Onaverage,CO
2
measurementswereunder1064ppm(averagedailyoutsideCO2
measurement+theASHRAErecommendedguidelineof700 ppm).However,whenthefacilitywasathighoccupancy,wefound CO
2levelsthatexceeded1064ppminpocketsaroundthemain
workarea.RefertoTable1formeasurementrangesandaverages.
Table 1*. Environmental condition measurements taken at AVPO Date Location Temp. (°F) RH (%) CO2 (ppm) CO (ppm)
Outside 86.7 17.8 330 0 July 11, 2007 Mail sorting area (low occupancy)
PM Range 70-74 25.5-30.5 547-745 0 Average 72 28 611 0 Outside 78 23.4 364 0
July 12, 2007 Mail sorting area (high occupancy) AM Range 69-71 26.1-32.3 633-1215 0
Average 71 29 875 0 * See Table B1 in Appendix B for ANSI/ASHRAE recommended thermal environmental condition levels.
Page � Health Hazard Evaluation Report 2007-0216-3056
Results And disCussion (Continued) Weobservedtheuseof2-inchmedium-efficiencyfiltersinthe
HVACunits.Prefilters,whichpreservetheintegrityofthemain filter,wereobservedinonlysomeoftheunits.Duringour inspection,wewereunabletotellifallthefilterswereinstalled correctlybecausethedirectionalarrowsonthefilterframes werenotalwaysvisible.Duetothepositionoftheoutdoorair dampersandpanelsintheHVACunits,wecouldnottellifthe damperswerecompletelyclosed.Closedornearlyclosedoutdoor airdamperslimittheamountofoutdoorairbroughtintothe building.
Wereleasedsmallpuffsofsmokeintotheairandobservedthe directionsmokeflowedtodeterminethegeneralairmixingand flowdynamicsinthearea.Thissmoketestwasdoneatbreathing zonelevelthroughoutthebuildingandweobservedthat,overall, thebuildingwasunderpositivepressure,whichmeansairmoves frominsidetooutsidethebuilding.Severalareasappearedtohave lowairflow.Thewomen’srestroomwasdeterminedtobeunder negativepressure(airflowsfromworkareaintobathroom,thenis ventedthroughtheroof)whichisrecommendedbyASHRAE,but themen’srestroomwasunderpositivepressure(airinbathroom flowsouttotheworkarea).
Weinspectedtwoairsupplyductsanddiffusers,oneontheceiling ofthemainworkingarea,theotherinanoffice.Blackparticles hadcollectedaroundthediffuserdeflectorsinapatternoftheair flow.Wedidnotobserveanyblackparticlesinsidetheduct.The blackparticulatemaybegeneratedinsidetheworkareaordrift intotheworkareafromtheoutside,whereitisthenimpacted ontothediffusersbythesupplyair.Aslongasfiltersareinstalled correctlyandtheHVACsystemisworkingproperly,theamountof particlesenteringtheroomfromtheductworkshouldbereduced, becauseairispassedthroughfiltersbeforereenteringthesupply duct.
ItwasreportedthatAVPOmaintenanceemployeesmayhave removedandcleanedthepigeonfecalmatterthemselvesbeforethe cleaningandsanitizingcompanywashired.Ifanyinfectiousagents arepresentinthefeces,itwouldbepossibleforaerosolizationto occurduringcleaningactivities.
Duringourwalk-throughofthebuilding,weobservedseveral looselightfixturesandstainedorsaggingceilingtiles.Thesharps boxinthemen’sbathroomhadfallenoffthewallandhadbeen
Health Hazard Evaluation Report 2007-0216-3056 Page �
ReCommendAtions (Continued) insecurelyreaffixedwithtape.Wealsoobservednumerousinsects
(blackbugs)inthemen’sroom.Workersreportedthatinsectshad beenpresentinofficesandotherlocationsofthebuildingfora considerableperiodoftime.
ConClusionsBaseduponmedicalinterviewswithworkersandanassessment ofenvironmentalconditionsattheAVPO,weconcludethat nodirectrelationshipexistsbetweencurrenthealthsymptoms reportedbyAVPOemployeesandspecificoccupationalor environmentalexposures.Perceivedodorandbuildingventilation issueslikelycontributedtothesesymptoms.Wefoundthatthe potentialforemployeestocontracthistoplasmosiswaslowand thispotentialwasfurtherminimizedbycleaningandinstalling netsaroundtheHVACunits.WedonotrecommendthatAVPO employeesbetestedforhistoplasmosis.However,ifindividual employeesfeelthattheyshouldbetestedduetotheirsymptoms, theyshoulddiscussthiswiththeirphysician.
Wefoundcomfortparametersatthepostofficetobewithin acceptableASHRAEguidelinesexceptforelevatedCO2
levels insomeworkareasduringhighoccupancy,possiblyindicating inadequateoutdoorairintake(possiblyduetoclosedormostly closedoutdoorairdampers)orunevenmixingofair.Allpigeon fecalmatterhadbeenclearedfromtheunitsweexaminedand, overall,thebirdnettingappearedintact.Atthetimeofour investigation,wesawtwobirdfeathersinoneoftheHVACunits, butnoevidencethatbirdswereenteringorstilllivingintheunit.
ReCommendAtions Basedontheobservationsandfindingsofthisevaluation,the followingrecommendationsareprovidedintheinterestof enhancinghealthandsafetyconditionsattheAVPO.
1. TestingofallAVPOemployeesforhistoplasmosisis notnecessaryandneednotbeconductedbecausethe potentialforcontractingsuchisverylow.Employeeswith healthproblemsshouldseekcarewiththeirphysicianfor appropriatemanagement.
2. Evenintheabsenceofinfectiousagents,anyemployee whowillberemediatinganimalfecesshouldbeprovided withhazardcommunicationinformationandappropriate PPE.Hazardcommunicationinformationshould includeawarningthatindividualswithcompromised
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ReCommendAtions (Continued) cell-mediatedimmunity(e.g.,anindividualwithHIV
infection,thelymphoma-leukemia-Hodgkin’sgroupof malignancies[cancers],orthoseonsteroidtherapyor otherimmunosuppressiveagents)areatgreaterriskof clinicaldiseaseshouldinfectionoccur.Individualswith compromisedcell-mediatedimmunityshouldbeadvised toconsulttheirpersonalphysicianconcerningtheneedto avoidexposuretomaterials(suchaslargeaccumulations ofoldpigeonfeces)possiblycontaminatedwithinfectious microorganisms.Onemethodofhazardcommunication includespostingsignsinappropriateareastoremind workersofthebirdfecesproblem.
3. Continuetomonitorthebirdnettingfordamageorholes toensurethatbirdsarenotabletonestintheHVACunits. Anygapsthatareidentifiedshouldbesealedimmediately.
4. TheHVACcontractor’sworkordernotedthattheyhad closedtheoutdoorairdampers.Toallowadequateintake ofoutdoorair,dampersshouldnotbecompletelyclosed. UseANSI/ASHRAEguidelinestodetermineminimum amountsofoutdoorairthatshouldbedeliveredintothe workareas[ANSI/ASHRAE2007].
5. SeveralhighCO2measurementsmayindicateinsufficient
outdoorairbeingbroughtintothebuilding,which mayimproveifdampersareopened.BasedontheCO
2
measurementsandsmoketuberesultsshowingareasof littleairmovement,atestandbalanceoftheventilation systemshouldbeperformed.Thecompanyperformingthe testingandbalancingshouldbecertifiedbytheNational EnvironmentalBalancingBureau(www.nebb.org)orother recognizedorganization.
6. Therestroomexhaustfansshouldbeevaluatedtoensure thatrestroomsareundernegativepressuresothatanyodors areexhaustedawayfromworkingareas.ANSI/ASHRAE standard62.1recommendsthatpublicrestroomshavea minimumexhaustrateof70cfmperunit(watercloset and/orurinal)whereperiodsofheavyuseareexpectedto occur,otherwisearateof50cfm/unitisacceptable[ANSI/ ASHRAE2007].
7. UseprefilterstoextendthelifeofthemainHVACair filters.Alsoensurethatthefiltersareplacedinthecorrect directioninrelationtoairflow.Filtersshouldbeplacedso thatflowdirectionarrowsareclearlyvisible,therebymaking iteasiertoobservewhetherfiltersareproperlyinstalled.
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ReCommendAtions (Continued) 8. Duetothedustyandwindyconditionsofthedesert,
considerinstallingapressure-sensingdevice,suchasa manometerorMagnehelicgaugetoprovideanaccurate andobjectivewayofknowingwhentochangeairfilters. Bycomparingthereadingsofapressure-sensingdevice whenthefilterisnewversusheavilyloaded(readytobe changed),alongwiththefiltermanufacturer’sinformation onpressuredropcharacteristics,youwillbeabletoreplace thefilterswhenneeded[NIOSH2003].Moreinformation onFiltrationandAir-CleaningSystemscanbefoundin theNIOSHdocument,“GuidanceforFiltrationandAir-CleaningSystemstoProtectBuildingEnvironmentsfrom AirborneChemical,Biological,orRadiologicalAttacks” athttp://www.cdc.gov/niosh/docs/2003-136/default. html#toc.
9. Performregularhousekeeping,includingdustingofsupply andexhaustventsandregulargeneraldustingtominimize particulatematter.Whenvacuuming,useanindustrial-typevacuumcleanerinstalledwithaHEPAfilter.We recommendfollowingthegreenorsustainablebuilding practice,whichaimstocreateahealthierandmoreresource-efficientmodelsofmaintenance.Additionalinformation onGreenBuildingscanbefoundattheEPAwebsite http://www.epa.gov/greenbuilding/.Informationon environmentalandhealth-friendlycleaningsuppliesand resourcesmaybefoundathttp://www.epa.gov/oppt/epp/ pubs/products/cleaner.htm.
10.Scheduleregularpestinspectionofthebuilding,andspray insecticideonlywhenneededandwhenthebuildingisnot occupied.Thiswillallowpesteliminationwhileminimizing employeeexposuretoinsecticides.
11.Continuetocommunicatewithbuildingoccupantsto discussissuesandsecureoccupants’cooperationwhen resolvingissuesorconcerns.Itisimportanttocontinue recording,respondingto,andresolvinghealthandsafety issuesinatimelymannertopreventthemfrombecoming majorhealthorcomfortproblems.TheHealthandSafety Committeememberscanhelpwiththisissue.
12.Replacestainedorsaggingceilingtilesandreaffixloose, hanginglightingfixtures.
13.Thesharpsboxinthemen’sroomshouldbesecurelyfixed tothewalltopreventaccidentalsharpinjuries.
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RefeRenCes AmesRG,StrattonJW[1991].Acutehealtheffectsfrom communityexposuretoN-propylmercaptanfromanethoprop (Mocap)-treatedpotatofieldinSiskiyouCounty,California.Arch EnvironHealth46(4):213–217.
ANSI/ASHRAE[2007].Ventilationforacceptableindoor airquality.AmericanNationalStandardsInstitute/ASHRAE standard62.1-2007.Atlanta,GA:AmericanSocietyofHeating, Refrigerating,andAir-ConditioningEngineers,Inc.
ANSI/ASHRAE[1999].Methodoftestinggeneralventilationair cleaningdevicesforremovalefficiencybyparticlesize.American NationalStandardsInstitute/ASHRAEstandard52.2.Atlanta, GA:AmericanSocietyforHeating,Refrigerating,andAir-ConditioningEngineers,Inc.
BruvoldWH,RappaportSM,WuTC,BulmerBE,DeGrange CE,KoolerJM[1983].Determinationofnuisanceodorina community.JWaterPollControlFed55:229–233.
CrandallMS,SieberWK[1996].TheNationalInstitutefor OccupationalSafetyandHealthindoorenvironmentalevaluation experience.Partone:buildingenvironmentalevaluations.Appl OccupEnvironHyg11(6):533–539.
DaltonP[1999].Cognitiveinfluencesonhealthsymptomsfrom acutechemicalexposure.HealthPsychol18:579–590.
DeepeGS[2004].Histoplasmacapsulatum.In:MandellGL, BennettJE,DolinR,eds.Principlesandpracticeofinfectious diseases.6thed.Vol.2.Philadelphia:ChurchillLivingstone Publisher,pp.3012–3025.
ErdmannCA,ApteMG[2004].Mucousmembraneandlower respiratorybuildingrelatedsymptomsinrelationtoindoorcarbon dioxideconcentrationsinthe100-buildingBASEdataset.Indoor Air14Suppl8:127–134.
LindgrenT,NorbackD[2005].Healthandperceptionofcabin airqualityamongSwedishcommercialairlinecrew.IndoorAir15 Suppl10:65–72.
NagdaNL,HodgsonM[2001]. Lowrelativehumidityandaircraft cabinairquality.IndoorAir 11(3):200–214.
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RefeRenCes (Continued) NIOSH[2003].Guidanceforfiltrationandair-cleaningsystemsto protectbuildingenvironmentsfromairbornechemical,biological, orradiologicalattacks.Cincinnati,OH:U.S.Departmentof HealthandHumanServices,PublicHealthService,Centers forDiseaseControlandPrevention,NationalInstitutefor OccupationalSafetyandHealth,DHHS(NIOSH)PublicationNo. 2003-136.
NIOSH[2004].Histoplasmosis:Protectingworkersatrisk. Cincinnati,OH:U.S.DepartmentofHealthandHuman Services,PublicHealthService,CentersforDiseaseControland Prevention;NationalInstituteforOccupationalSafetyandHealth. DHHS(NIOSH)PublicationNo.2005-109.[http://www.cdc.gov/ niosh/docs/2005-109/]Dateaccessed:September5,2007.
PerfectJR[2004].Cryptococcusneoformans.In:MandellGL, BennettJE,DolinR,eds.Principlesandpracticeofinfectious diseases.6thed.Vol.2.Philadelphia:ChurchillLivingstone Publisher,pp.2997–3009.
RoseCS[2005].Hypersensitivitypneumonitis.In:MasonRJ, BroaddusVC,MurrayJF,NadelJA,eds.MurrayandNadel’s textbookofrespiratorymedicine.4thed.Philadelphia:Elsevier SaundersPublisher,pp1783–1794.
RosenstockL[1996].NIOSHTestimonytotheU.S.Department ofLaboronindoorairquality.ApplOccupEnvironHyg 11(12):1365–1370.
SchlossbergD[2004].Chlamydophilia(Chlamydia)psittaci (Psittacosis).In:MandellGL,BennettJE,DolinR,eds.Principles andpracticeofinfectiousdiseases.6thed.Vol.2.Philadelphia: ChurchillLivingstonePublisher,pp.2256–2258.
SeppanenOA,FiskWJ,MendellMJ[1999].Associationof ventilationratesandCO concentrationswithhealthandother
2
responsesincommercialandinstitutionalbuildings.IndoorAir 9:226–252.
SkybergK,SkulbergKR,EduardW,SkaretE,LevyF,Kjuus H[2003].Symptomsprevalenceamongofficeemployeesand associationstobuildingcharacteristics.IndoorAir13(3):246–252.
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RefeRenCes (Continued) ShustermanD[1992].Criticalreview:thehealthsignificanceof environmentalodorpollution.ArchEnvironHealth47(1):76–87.
ZeidbergLD,AjelloL,WebsterRH[1955].Physicaland chemicalfactorsinrelationtoHistoplasmacapsulatumin soil.Science122:33–34.
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Appendix A: HeAltH effeCts
Histoplasmosis HistoplasmosisisaninfectiousdiseasecausedbyinhalingthesporesofafunguscalledHistoplasma capsulatum.Histoplasmosisisnotcontagious;itcannotbetransmittedfromaninfectedpersonoranimal tosomeoneelse.H. capsulatumgrowsinsoilsthroughouttheworld.Theproportionofpeopleinfectedby H. capsulatumishigherincentralandeasternstates(especiallyalongthevalleysoftheOhio,Mississippi, andSt.Lawrencerivers)andinanareaneartheRioGrande.Thefungusseemstogrowbestinsoils withhighnitrogencontent,especiallythoseenrichedwithbirdmanureorbatdroppings.Freshbird droppingsonsurfacessuchassidewalksandwindowsillshavenotbeenshowntopresentahealthrisk forhistoplasmosisbecausebirdsthemselvesdonotappeartobeinfectedbyH. capsulatum.Rather,bird manureisprimarilyanutrientsourceforthegrowthofH. capsulatumalreadypresentinsoil[NIOSH 2004].
Histoplasmosisprimarilyaffectsaperson’slungs,anditssymptomsvary.Thevastmajorityofinfected peopleareasymptomatic(havenoapparentilleffects),ortheyexperiencesymptomssomildtheydonot seekmedicalattentionandmaynotevenrealizethattheirillnesswashistoplasmosis.Ifsymptomsdo occur,theyusuallystartwithin3to17daysafterexposure,withanaverageof10days.Histoplasmosis canappearasamild,flu-likerespiratoryillnessandhasacombinationofsymptoms,includingmalaise(a generalillfeeling),fever,chestpain,dryornonproductivecough,headache,lossofappetite,shortnessof breath,jointandmusclepains,chills,andhoarseness.Rarely,amoreseveretypeofhistoplasmosisoccurs; personswhogetthemoreseveretypeofhistoplasmosisrequireantifungalmedicationstotreatthedisease [NIOSH2004].
Symptoms from Indoor Environmental Quality Thesymptomsreportedbybuildingoccupantsassociatedwithindoorenvironmentalconcernshave beendiverseandusuallyarenotsuggestiveofanyparticularmedicaldiagnosisorreadilyassociated withacausativeagent.Reportsdemonstratecloserassociationsofsymptomoccurrencewithoccupant perceptionsoftheindoorenvironmentratherthanwithanymeasurementofindoorcontaminantsor conditions[NIOSH1991;BerglundandCain1989].Atypicalspectrumofreportedsymptomsincludes headaches,fatigue,itchingorburningeyes,irritationoftheskin,nasalcongestion,dryorirritatedthroat, andotherrespiratorysymptoms.Thesesymptomsarealsooftenexperiencedbypeopleoutsideofthe workplaceandcouldberelatedtoanumberofdifferentcauses,suchasrespiratoryinfections,allergies, discomfortduetotemperatureandhumidity,andstress.Somestudieshaveshownthatpsychological, social,andorganizationalfactorsmaymodifyindividuals’andorganizations’responsestoconcernsin theofficeenvironment[Boxer1990;Ooi1997;Baker1989].Typically,workerssuspectaworkplacecause becausetheirsymptomsappeartobeworsewhileatworkandbetterwhenawayfromwork.
Lessoften,illnessesandreactionsmaybefoundtoberelatedtospecificexposuresincertainbuilding environments.Hypersensitivitypneumonitis,Legionnaires’disease,Pontiacfever,andCOpoisoningare allcausedbyspecificagent(s)thathavebeenfoundinsomebuildingenvironments.Thefirstthreeofthese conditionscanbecausedbymicroorganisms.
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Appendix B: AdditionAl infoRmAtion on ieQ issues
TemperatureandRHmeasurementsareoftencollectedaspartofanIEQinvestigationbecausethese parametersaffecttheperceptionofcomfort.TheANSI/ASHRAE Standard 55-2004:Thermal Environmental Conditions for Human Occupancy,specifiesconditionsinwhich80%ormoreoftheoccupantsareexpected tofindtheenvironmentthermallyacceptable[ANSI/ASHRAE2004].Temperaturesrecommendedby ANSI/ASHRAErangefrom68.5oFto77.0oFinthewinter,and75.0oFto81.5oFinthesummer(seeTable B1below).Thedifferenceislargelyduetoseasonalclothingselection.ANSI/ASHRAEalsorecommends thatRHbemaintainedatorbelow65%.TheUnitedStatesEPArecommendsmaintainingindoorRH between30%–50%.Valuesoutsidetheserangeshavebeenfoundtoproducesymptoms.RHbelow30% hasbeenshowntobeassociatedwithsymptoms[Wolkoffetal.2006;NagdaandHodgson2001],which maycontributetosomeofthesymptomsexperiencedbytheoccupants.Morespecificinformationon IEQissues,guidancetoolsformanagingIEQ,andventilationandcontrolstudiesoflarge,commercial buildingsmaybefoundattheEPAwebsite,http://www.epa.gov/iaq/largebldgs/index.html.
Table B1. ANSI/ASHRAE recommended thermal environmental conditions.
Relative Humidity (%) Winter Temperatures (oF) Summer Temperatures (oF)
30 69.5 to 77.0 75.5 to 81.5
40 69.0 to 76.5 75.5 to 81.0
50 68.5 to 76.0 75.0 to 80.5
References
ANSI/ASHRAE[2004].Thermalenvironmentalconditionsforhumanoccupancy.American NationalStandardsInstitute/ASHRAEstandard55-2004.Atlanta,GA:AmericanSocietyforHeating, Refrigerating,andAir-ConditioningEngineers,Inc.
BakerDB[1989].Socialandorganizationalfactorsinofficebuilding-associatedillness.OccupMed 4(4):607–624.
BerglundL,CainWS[1989].Perceivedairqualityandthethermalenvironment.In:Proceedings of IAQ ‘89: The Human Equation: Health and Comfort.Atlanta,GA:AmericanSocietyofHeating,Ventilating,andAir-ConditioningEngineers,pp.93–99.
BoxerPA[1990].Indoorairquality:apsychosocialperspective.JOccupMed32(5):425–428.
NagdaNL,HodgsonM[2001].Lowrelativehumidityandaircraftcabinairquality.IndoorAir11(3):200– 214.
NIOSH[2005].Histoplasmosis:Protectingworkersatrisk.Cincinnati,OH:U.S.DepartmentofHealth andHumanServices,PublicHealthService,CentersforDiseaseControlandPrevention;National
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Appendix B: AdditionAl infoRmAtion on ieQ issues (Continued)
InstituteforOccupationalSafetyandHealth.DHHS(NIOSH)PublicationNo.2005-109.[http://www. cdc.gov/niosh/docs/2005-109/]Dateaccessed:September5,2007.
NIOSH[1991].Hazardevaluationandtechnicalassistancereport:LibraryofCongress,Washington.D. C.Cincinnati,OH:U.S.DepartmentofHealthandHumanServices,PublicHealthService,Centersfor DiseaseControl,NationalInstituteforOccupationalSafetyandHealth,NIOSHReportNo.HHE88-364-2104.
OoiPL,GohKT[1997].Sickbuildingsyndrome:anemergingstress-relateddisorder?IntJEpidemiol 26(6):1243–1249.
WolkoffP,NojgaardJK,FranckC,SkovP[2006].Themodernofficeenvironmentdesiccatestheeyes? IndoorAir16(4):258–265.
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ACknowledgements And
AvAilABility of RepoRt TheHazardEvaluationandTechnicalAssistanceBranch(HETAB) oftheNationalInstituteforOccupationalSafetyandHealth (NIOSH)conductsfieldinvestigationsofpossiblehealthhazards intheworkplace.Theseinvestigationsareconductedunderthe authorityofSection20(a)(6)oftheOccupationalSafetyand Health(OSHA)Actof1970,29U.S.C.669(a)(6)whichauthorizes theSecretaryofHealthandHumanServices,followingawritten requestfromanyemployersorauthorizedrepresentativeof employees,todeterminewhetheranysubstancenormallyfound intheplaceofemploymenthaspotentiallytoxiceffectsinsuch concentrationsasusedorfound.
HETABalsoprovides,uponrequest,technicalandconsultative assistancetofederal,state,andlocalagencies;labor;industry;and othergroupsorindividualstocontroloccupationalhealthhazards andtopreventrelatedtraumaanddisease.Mentionofcompany namesorproductsdoesnotconstituteendorsementbyNIOSH.
ThisreportwaspreparedbyLiliaChenandAyodeleAdebayoof HETAB,DivisionofSurveillance,HazardEvaluationsandField Studies(DSHEFS).DesktoppublishingwasperformedbyRobin Smith.EditorialassistancewasprovidedbyEllenGalloway.
Copiesofthisreporthavebeensenttoemployeeandmanagement representativesatAppleValleyPostOffice;andtheOSHA RegionalOffice.Thisreportisnotcopyrightedandmaybefreely reproduced.Thereportmaybeviewedandprintedfromthe followinginternetaddress:http://www.cdc.gov/niosh/hhe.Copies maybepurchasedfromtheNationalTechnicalInformationService (NTIS)at5825PortRoyalRoad,Springfield,Virginia22161.
Health Hazard Evaluation Report 2007-0216-3056 Page ��
Recommended Citation for this report. NIOSH [2008]. Health Hazard Evaluation Report: Evaluation of Histoplasmosis
U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and
occupational safety and health topics, contact NIOSH at: 1-800-CDC-INFO (1-800-232-4636)
E-mail: [email protected]
or visit the NIOSH web site at:
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