Investigation of Employee Symptoms at an Indoor Waterpark

Investigation of Employee Symptoms at an Indoor Waterpark Lilia Chen MS Bich Dang MD Charles Mueller MS Kevin H Dunn MS CIH Daniel Almaguer MS Jennifer L Ernst BS Charles S Otto III MPS RS

Health Hazard Evaluation Report HETA 2007-0163-3062 Great Wolf Lodge Mason Ohio June 2008

DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention

WorkplaceSafety and Health

National Institute for Occupational 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

HighlightsoftheNIOSHHealthHazardEvaluation iv

Summary vi

Introduction1

Assessment7

Results11

Discussion19

Conclusions30

Recommendations31

References33

Appendix A Tables37

Appendix B Methods41

Appendix C OccupationalExposureLimitsandHealthEffects44

ACknowledgements AcknowledgementsandAvailabilityofReport52

Health Hazard Evaluation Report 2007-0163-3062 Page

ABBReviAtions

ACGIHreg AmericanConferenceofGovernmentalIndustrialHygienists ACH Airchangesperhour ASHRAE AmericanSocietyofHeatingRefrigeratingandAirConditioningEngineers ANSI AmericanNationalStandardsInstitute CDC CentersforDiseaseControlandPrevention CFD Computationalfluiddynamics cfm Cubicfeetperminute cm Centimeter DBP Disinfectionby-products DIN DeutschesInstitutfuumlrNormungeV(GermanInstituteforStandardization) DPD NNdiethyl-p-phenylenediamine EU Endotoxinunit ft Feet gL Gramsperliter GWL GreatWolfLodge HVAC Heatingventilatingandairconditioning INRS InstitutNationaldeRechercheetdeSecurite(NationalInstituteofResearchandSafety) LAL Limulusamoebocytelysate LOD Limitofdetection LOQ Limitofquantitation mgL Milligramsperliter mgm3 Milligramspercubicmeter mL Milliliter mj Millijoule mm Millimeter NAICS NorthAmericanIndustryClassificationSystem NCEH NationalCenterforEnvironmentalHealth NIOSH NationalInstituteforOccupationalSafetyandHealth no Number OEL Occupationalexposurelimit OSHA OccupationalSafetyandHealthAdministration PBZ Personalbreathing-zone PEL Permissibleexposurelimit ppm Partspermillion REL Recommendedexposurelimit RH Relativehumidity RLV Relativelimitvalue SQRT Squareroot STEL Shorttermexposurelimit TLVreg Thresholdlimitvalue TWA Time-weightedaverage microg Microgram

Page Health Hazard Evaluation Report 2007-0163-3062

ABBReviAtions (Continued)

microm Micrometer UV Ultraviolet WCCHD WarrenCountyCombinedHealthDistrict WEEL Workplaceenvironmentalexposurelevel WHO WorldHealthOrganization


HigHligHts of tHe

niosH HeAltH

HAzARd evAluAtion

The Warren County Combined Health District asked the National Institute for Occupational Safety and Health (NIOSH) to assist in investigating the cause of symptoms reported at the Great Wolf Lodge (GWL) indoor waterpark resort in Mason Ohio Symptoms included cough wheezing shortness of breath eye and nose irritation and skin rashes We conducted our investigation in March and April 2007

What NIOSH Did Wetestedtheairfortrichloraminesolublechlorine

compoundsandendotoxin

WetestedthewaterforfecalcontaminationLegionella mycobacteriaendotoxinsulfitesandsulfates

Wecheckedthewaterchemistryandreviewedthewater systemdesign

WeadministeredquestionnairestoGWLemployeesabout theirhealth

Wereviewedtheventilationsystemdesign

What NIOSH Found Wefoundtrichloramineconcentrationssimilartolevels

foundinotherindoorswimmingpoolstudiesandsome wereatlevelsreportedtocausemucousmembraneirritation

Wefoundairendotoxinconcentrationsatlevelsthathave beenassociatedwithcoughandfever

WedidnotfindfecalcontaminationLegionella mycobacteriasulfitesorsulfatesinthepoolwater

WefoundthatwaterchemistryresultsmetOhiostate standards

Wefoundthatlifeguardshadmorework-relatedsymptoms thanemployeesnotworkinginsidetheindoorpoolarea

Wefoundthatlifeguardshadmorework-relatedcoughand eyeirritationondayswhenthenumberofpeopleusingthe indoorpoolareawashigh

Wefoundthattheventilationsystemdesignmaynotprovide adequateairmovementanddistribution

What Managers Can Do Managersshouldfurtherassesstheventilationsystem

toensureenoughairmovementandproperremovalof contaminants

Managersshouldconsiderreducingwaterattractioncycle timesandusinglargerdropletdischargenozzlestoreduce aerosolizationofcontaminants

Managersshouldconsiderredesigningthesprayfeature pipingsystemtomakesurethatwaterusedinthepoolsis takendirectlyafterthefiltrationandtreatmentcycle

Page v Health Hazard Evaluation Report 2007-0163-3062

HigHligHts of tHe Managersshouldmonitoranddocumentanysymptoms niosH HeAltH reportedbyemployeesandpatrons

HAzARd evAluAtion What Employees Can Do(Continued) Employeesshouldreportanysymptomsthatmaybework-

relatedtotheirsupervisors

Health Hazard Evaluation Report 2007-0163-3062 Page v

summARy

Lifeguards had significantly more work-related symptoms than employees who did not work in the indoor pool area they had more symptoms on days when hotel occupancy was high We found airborne chloramines and endotoxin which may have contributed to reported symptoms We recommend evaluating the ventilation system design to identify ways to increase air movement and reduce air contaminant levels at the pool deck level

InMarch2007NIOSHreceivedatechnicalassistancerequest fromtheWCCHDtoinvestigatethecauseofsymptomsreported byemployeesattheGWLindoorwaterparkresortinMason OhioReportedsymptomsincludedrespiratorysymptomseyeand noseirritationandskinrashes

InMarch2007wevisitedthesiteforthefirsttimeWemetwith managementWCCHDrepresentativesandanemployeelifeguard representativetouredthefacilityandinterviewedworkersina privatesetting

InMarchandApril2007wecollectedareaairsamplesfor trichloraminesolublechlorinecompoundsandendotoxin WealsomeasuredairtemperatureandRHandadministered questionnairestoemployeesregardingmedicaljobandpersonal historyandwork-relatedsymptomsWaterchemistrytestswere performedandwatersampleswerecollectedforLegionellafecal coliformbacteriamycobacteriaendotoxinsulfitesandsulfates Areviewwasconductedofthewatersystemandventilationsystem designs Thetrichloramineconcentrationswemeasuredweresimilarto thosefoundinotherindoorswimmingpoolstudiesandsome wereatlevelsreportedtocausemucousmembraneirritationAir endotoxinlevelsinallpoolareasexceptthewaterfortexceeded theACGIHproposedRLVforendotoxinexposure(10times thebackgroundlevelwhensymptomsconsistentwithendotoxin exposurearereported)WaterchemistryresultsmetOhiostate standardsNoLegionellamycobacteriaorfecalcoliformbacteria werefoundinanyofthewatersamplescollected

Lifeguardshadsignificantlymorework-relatedrespiratory symptomseyeandnoseirritationfeverbodyachesandskin rashesinthe4weekspriortoquestionnairecompletionthan employeeswhodidnotworkintheindoorpoolareaThe prevalenceofwork-relatedcoughandeyeirritationamongthe lifeguardswassignificantlyhigherondayswhenhoteloccupancy washigh

Ventilationdesignconcernsincludetheplacementofairsupply diffusersandreturnairinletsatheightsof30ndash80ftabovedeck levelThisheightmakesitdifficulttoprovideadequateair movementandmixingatthepoolsurfaceanddecklevelsand createsthepotentialforshortcircuitingofsupplyairtoexhaust


summARy(Continued) Thisreportcontainsrecommendationsfordecreasingthe

chloramineexposuresthoughttocausethereportedsymptoms includingmodificationandredesignoftheventilationsystemto increaseairmovementatthepooldecklevel

Keywords NAICS 713990 (All Other Amusement and Recreation Industries) chloramines trichloramine nitrogen trichloride indoor waterpark pools hot tubs spas sulfates sulfites endotoxin fecal coliform relative humidity Legionella mycobacteria cough respiratory symptoms rash eye irritation


Thispageintentionallyleftblank

intRoduCtion InMarch2007NIOSHreceivedatechnicalassistancerequest fromtheWCCHDtoinvestigatethecauseofsymptomsreported byemployeesattheGWLindoorwaterparkresortinMason OhioReportedsymptomsincludedcoughwheezingshortness ofbreathchesttightnesssorethroateyeandnoseirritationand skinrashes

TheWCCHDbeganreceivinghealthcomplaintsfromGWL patronsinJanuary2007GWLmanagementrespondedby inspectingtheventilationsystemwaterfiltrationsystemand waterchemistryWaterchemistrytestswerealsoperformed bytheWCCHDandresultscompliedwithstatecodes[Ohio DepartmentofHealth2003]GWLhiredaconsultanttotake chlorineairsamplesonJanuary312007Theninechlorineair samplesweretakenover15minutesatvariouslocationsinthe poolareaandhadconcentrationsbelowtheNIOSHRELof05 ppmandtheOSHAPELof1ppmChlorinelevelswerehighest aroundtheleisureriverattractionat04ppmEventhoughthis levelwasbelowboththeNIOSHRELandOSHAPELGWL addedtwosupplydiffuserstotheairductsabovethisareaand onesupplydiffuserabovethehottubareaonMarch92007 GWLalsoincreasedwaterchemistrychecksfromevery4hours toevery2hoursreducedwaterchlorineconcentrationstothe lowestconcentrationpossiblewhilestillmaintainingitabovethe minimumstate-requiredlevelreducedpHloweredairtemperature andhumiditylevelsandaddedmorefreshwatertoallsystems HoweverWCCHDcontinuedtoreceivehealthcomplaintsfrom patronspromptingatechnicalassistancerequesttoNIOSH

InMarch2007wevisitedthesiteforthefirsttimeDuringthe sitevisitwemetwithmanagementWCCHDrepresentatives andanemployeelifeguardrepresentativetouredtheindoor waterparkandprivatelyinterviewedseverallifeguardsabouttheir medicalstatusMostoftheinterviewedlifeguardsreportedeyeand respiratoryirritationatworkTheyalsoreportedrecurrentcough withfeverLifeguardsreportedthattheirsymptomswereworse whenthebatherload(numberofpeopleusingtheindoorpool area)washighandwhenoutdoorairtemperatureswerecolder Basedonthosemedicalinterviewswedeterminedthatfurther investigationwaswarranted

InMarchandApril2007wecollectedareaairsamplesfor trichloraminesolublechlorinecompoundsandendotoxin WealsomeasuredtemperatureandRHandadministered


intRoduCtion (Continued) questionnairestoemployeesregardingmedicaljobandpersonal

historyaswellaswork-relatedsymptomsWaterchemistrytests wereperformedandwatersampleswerecollectedforLegionella fecalcoliformbacteriamycobacteriaendotoxinsulfitesand sulfatesAreviewwasconductedofthewatersystemandair distributionsystemdesignsAninterimletterwasprovidedon April92007withthepreliminaryresultsoftheairsampling performedonMarch202007

Process Description

GWLisanindoorwaterparkresortchainwith10locations acrosstheUnitedStatesTheMasonOhiofacilityopened onDecember142006andincludesroomsuitesanindoor waterparkconferencecenterfitnesscenterrestaurantsshops andanarcadeTheOhioDepartmentofAgriculturersquosDivision ofAmusementRideSafetymaintainsjurisdictionoverthe aquaticamusementridesandassociatedpoolsandtheWCCHD maintainsjurisdictionoverthetwohottubsTheapproximately 80000-ft2waterparkhas11waterslidestwoactivitypoolstwo hottubsawavepoolaleisureriverafour-storyinteractiveplay systemandavarietyofwaterfeaturesthatsplashsprayandaerate largeamountsofwaterThetotalwatervolumeattheGWLisover 400000gallonsthetotalwatersurfaceareaisover15000ft2and thedepthrangesfrom0to5ftThemaximumoccupancyforthe waterparkis3746[OhioFireCode2006]andguestscanvisitthe poolareafrom9amto10pm

GWLemploysabout500employeesattheMasonfacilityOfthe approximately100lifeguards50ndash60areunder18yearsofage Duetoemployeeturnoverthenumberoflifeguardsfluctuates butapproximately30workfull-timeand70workpart-time Lifeguardsworkmainlytwoshifts830amto430pmand400 pmto1100pmwithafewworkingthe1100amto800pm breakshiftLifeguardspatroladefinedsectionofthewaterpark androtatethroughdifferentlocationsevery30minutes

Water Systems

TheGWLhassevenmajorwatersystemsthatcirculatedisinfect andfilterwater24hoursadayEachwatersystemisself-contained withindividualmonitoringandregulatingcomponentsWater flowsbygravitythroughthemaindrainsandguttersystemsfrom


intRoduCtion (Continued) thepoolintodesignatedsurgetanksWaterforthesprayfeaturesis

drawndirectlyfromthesurgetanksHowevermostofthewateris pumpedoutofthesurgetankintothefiltrationsystemThefilter containssyntheticdiatomaceousearthfiltermediawhichremoves particlesdownto10micron[Zajo2008a]Filterbedsareagitated nightlytoredistributethefiltermediaandaccumulateddebrisinto auniformfilteringsurfaceFiltermediaisreplacedapproximately every3weeksThefilterinfluentandeffluentpressureischecked dailytomonitorthefiltrationefficiency

ThefilteredwaterthenpassesthroughaUVunitwhichoperates ataminimumof60mjcm2tobreakdowncombinedchlorineand providesecondarydisinfectionNaturallyoccurringlevelsofiron ormanganeseintheincomingpublicwatersupplymaydeposit asaresidueontheUVquartzsleevesWhenenoughresidue accumulatessothatthelightemittedthroughthequartzsleeve fallsbelow60mjcm2areal-timemonitoringsensorintheUV unitshowsalowdosereadingAdditionallytechnicianscheckthe sensorreadingsevery2hoursIfalowdosereadingisobserved thefouledsleevesarecleanedwithadiluteacidsolutiontoremove theresidue

Thewaterthenpassesthroughanautomatedchemicalcontroller systemthatmonitorsandmaintainswaterpHandfreechlorineAs neededthecontrollerinjectssulfuricacidsolution(toadjustthe pHofthewater)andsodiumhypochloritesolution(todisinfect thewater)intotherecirculationpipeAfterthewaterchemistryis adjustedthewaterisheatedtomaintainpooltemperatureThe wateristhensentbacktothepoolthroughfloordiffusers

Inadditiontotheautomatedchemicalcontrollersystem techniciansmanuallycheckwaterchemistryparametersincluding pHalkalinityfreechlorineandcombinedchlorineTechnicians takewatersamplesfromvalvesinstalledineachofthesystems neartheautomatedchemicalcontrollersandtestwaterchemistry TheresultsarerecordedinalogbookWatersamplesarealso collectedpoolsideatelbow-lengthdepthduringparkopeningand closingtimesandarecomparedwiththeautomatedchemical controllerreadingsGWLaimstomaintainpHbetween72and 74combinedchlorinelessthan02ppmandfreechlorine concentrationsbetween12and16ppmGWLrsquostargetrangefor totalchlorineis15to20ppmforpoolsand25to30ppmfor thehottubs


intRoduCtion (Continued) Waterlevelsarecheckedvisuallyevery2hoursbytechnicians

andcontinuouslybyautomatedautofilldevicesAnautofill devicemonitorsthewaterlevelbyusingfloatsinthesurge tanksandaddsfreshwaterwhenthewaterlevelfallsbelowa predeterminedsetpointGWLreplacesallwaterfromthefamily andadulthottubsatleastonceaweekTechniciansalsoperform acompletewaterchangeofthehottubsifthecombinedchlorine concentrationsriseabovesetlevels

ThewaterforGWLrsquoswaterfeaturescomesfromseparatewell fieldsonelocatedontheeastsideoftheLittleMiamiRiver BuriedValleyAquiferandtheotheratShakerCreekBuried ValleyAquiferIronandmanganeseareremovedbyaerationand filtrationfluorideandchlorineareaddedThesupplywaterisnot chloraminated

Ventilation System

Eightairhandlingunitsprovideheatingandventilationtothe GWLindoorwaterparkareaEachunitisdesignedtoprovide anairsupplyflowrateof18830cfmtothewaterparkthrougha 48-inchdiametermainductTheactualflowratehowevermay differdependingonthesystemdesignandinstallationTheunits operateindifferentmodesdependingonoutsideenvironmental conditionsandcontrolsetpointsTheunitsalsorecoverheatfrom theexhaustairThecontrolsetpointsforeachairhandlingunit are86ordmFairtemperatureand83ordmFwatertemperature[Zajo2008a] TheRHsetpointrangeis55ndash65Feedbackfromtemperature andhumiditysensorsinthereturnairductsofeachindividual airhandlingunitisusedtomaintaintheoveralltemperatureand humiditywithinthecontrolsetpoints

Whentheoutdoorairtemperatureisabove40ordmFtheairhandling unitsprovide100outdoorairwithnoairrecirculation[Neuman 2007]Below40ordmFtheairhandlingunitsrecirculateanincreasing amountofairtoamaximumof33(minimum67outdoor airsupply)basedontheoutdoorairtemperatureTworeturn airintakesarelocatedatdeckheightalongthenorthwallofthe waterparknearthefamilyhottubpoolandthewavepoolEach oftheseintakesreturnsapproximately19000cfmtotheair handlingunitsAnadditionalfourreturnairintakesarelocated approximately60ndash80ftabovethepooldeckonthenorthwallof themiddlehighbayareaofthewaterparkThesefourhighbay returnairductsare48inchesindiameterandreturnapproximately


intRoduCtion (Continued) 38000cfmeachAccordingtodesigndrawings70ofthereturn

airispulledfromthehighbayareaandapproximately30is pulledfromthelowerreturnairintakes

Theairhandlingunitshavethecapabilitytorecirculate100of thewaterparkairwhileintheldquounoccupiedmoderdquoThismodecan besetbasedonatimerorconditionsinthefacilityTheunitsare programmedtogointotheunoccupiedmodeonehalfhourafter thefacilityclosesuntil2hoursbeforethefacilityopensHowever theunitsmayremainintheldquooccupiedmoderdquoduringthesetimesif thehumidityinthefacilityisgreaterthan40RH

Airissuppliedtothewaterparkthroughaseriesof48-inch diameterductsthatrunalongtheceilingTheairsupplyductsare equippedwithdrum-typediffuserstypically10x30inchesinsize withasupplyflowrateofapproximately1800cfmeachInsome locationsalongthemainductsmallerdiffuserswithlowersupply airflowratesareusedThemainductdiameterisreducedinsizeas itextendsfurtherfromtheairhandlingunittoprovidebalancing ofairflowthroughtheoutermostairsupplydiffusersTheair supplydiffusersarelocatedapproximatelybetween30ndash80ftabove deckleveldependingonthelocationandthereturnairducts arelocatedbetween60ndash80ftabovedecklevelThefourmajorair supplyductsservice(1)leisureriverandwaterslide(2)leisure riverwavepoolandsouthconcessionarea(3)activitypoolsand playstructureand(4)childrenrsquosactivitypoolandhottubsTwo airhandlingunitssupplyeachoftheseductsdeliveringanominal flowrateofapproximately38000cfm

Association of Chloramines and Symptoms in Indoor Pool Environments

Numerouscasereportsofeyeandupperrespiratorytractirritation amongbathersandemployeeshavebeenreportedatchlorinated indoorswimmingpoolsAlthoughmanyDBPscanbeproduced bythemixtureofdisinfectantsandcompoundsfoundinpool waterchloraminesspecificallytrichloraminearesuspectedasa primarycauseofreportedirritationsymptomsbasedonexposure monitoringstudies[Heryetal1995Massinetal1998] ChloraminesareDBPsthatformwhenchlorinecombineswith nitrogen-containingcompoundssuchassweatandurineThey includetheinorganiccompoundsmonochloraminedichloramine andtrichloramineIncreasedbatherloadhasbeensignificantly


intRoduCtion (Continued) associatedwithanincreaseintrichloraminelevels[Jacobset

al2007]Thisismostlikelyduetotheincreaseintheamount ofnitrogencompoundsproducedsweatcontainsabout1gL ofnitrogen[WHO2006]andtheaverageamountofurine releasedintopoolwatersperbatheris25to30mL[Gunkeland Jessen1988]Behaviormodificationssuchasshoweringbefore enteringandleavingthepoolareaandtakingbathroombreaks candecreasetheamountofnitrogenouswastecontaminating poolwater[Dziubanetal2006]Otherfactorsaffectingthe chloramineconcentrationinindoorpoolenvironmentsinclude waterchemistryparameters(egchlorineconcentrationpH temperature)aerosolizationofparticlescausedbysplashingand sprayingandairrecirculation[Heryetal1995Massinetal 1998]

Trichloramineismorevolatilethanmonochloramineand dichloramineandisthemainchloraminecompoundpresent abovechlorinatedwatersurfaces[Holzwarthetal1984]Itisa strongmucousmembraneirritant[Barbee1983]andhasbeen associatedwitheyeandupperrespiratorytractirritationin swimmersandpoolattendants[Massinetal1998]Trichloramine poseslessofahealthconcerninoutdoorswimmingpoolsbecause itdissipatesintotheearthrsquosatmosphereHoweverenclosedindoor swimmingpoolscombinedwithinadequateventilationandpoor waterchemistrycontrolcancauseairborneDBPstoaccumulate

ResearchersattheINRSinFrancedevelopedasamplingand analyticmethodformeasuringchloraminesintheair[Heryetal 1998]NIOSHinvestigatorshavedevelopedadraftmethodthatis amodificationoftheINRSmethodAdetaileddescriptionofthe NIOSHsamplingandanalyticalmethodcanbefoundinAppendix BThesesamplingandanalyticmethodshavebeenusedina varietyofworkplacesincludingindoorswimmingpoolspoultry facilitiesandagreensaladprocessingplantwherechloramine exposurehasbeenlinkedtoeyeandupperrespiratoryirritation [Heryetal1995Heryetal1998NIOSH2003NIOSH2006]

AdditionalinformationonOELsandhealtheffectsofchloramines canbefoundinAppendixC


Assessment Water

OnMarch202007representativesfromWCCHDNIOSH andNCEHtouredtheaquaticfacilityincludingchemicalstorage disinfectionmonitoringandinjectionrecirculationandfiltration systemsandthesevenaquaticfeaturesPoolwaterwastestedfor pHfreeandtotalchlorineandalkalinityTheNCEHinvestigator reviewedtheconstructionplanstoassesswatersystemdesign includingwaterrecirculationfiltrationanddisinfectionprocesses

OnMarch282007environmentalhealthstafffromtheWCCHD andtheOhioDepartmentofHealthcompletedtheCDC EnvironmentalHealthOutbreakInvestigationSurveytoassistthe overallinvestigationThisenvironmentalhealthsystemassessment includedacomprehensivereviewoftheaquaticfacilityincludinga descriptionofthewatersystemswaterflowandtreatmentdesign andhygienepoliciesandpractices

Ventilation

Weinterviewedmaintenancemanagersandtheventilation designcontractortoobtaininformationontheoperationand maintenanceoftheairdistributionsystemsAvisualinspection wasmadeoftheventilationsystemservingthepoolareaincluding theairhandlingunitsandheightandlocationofsupplyand returndiffusersParameterssuchaspoolanddeckareaoverallair supplyflowrateandairchangeratesweredeterminedusingcopies ofmechanicalplansblueprintsandairhandlingunitdrawings providedbyGWLandtheirventilationcontractorNominal designairsupplyflowratesprovidedontheairhandlingunit drawingswerecomparedtothosemeasuredbyanindependenttest andbalancetechniciancertifiedbytheNationalEnvironmental BalancingBureauin2007Thetotalsquarefootageandvolume oftheindoorwaterparkareawerecalculatedandusedtocompute outsideventilationratesperpoolanddeckareaforcomparison withbuildingcodeandconsensusstandardsWealsocontacted theMasonbuildinginspectortodiscusstheOhioBuildingCode andinspectionprocess

Industrial Hygiene

Wehavehighlightedthesamplingmethodologyinthesections belowAdditionaldetailsonsamplingandanalyticalmethodscan befoundinAppendixB


Assessment (Continued) Chloramine Measurements

Trichloramineandsolublechlorinecompounds(monochloramine dichloraminehypochlorousacidandhypochlorite)werecollected usingthesamesamplingtrainthereforeunlessspecifiedtheterm chloraminesreferstobothtrichloramineandsolublechlorine compounds

Toassesstheeffectofbatherloadonairchloraminelevelswe collectedareaairsamplesforchloraminesonhighandlowbather loaddays(asapproximatedbyhoteloccupancy)March20(1153 guestsbooked)andApril14(1308guestsbooked)wereselectedas highbatherloaddaysandApril24wasselectedasalowbather loadday(70guestsbooked)NoPBZsamplesweretakenbecause PBZsamplingequipmentattachedtothelifeguardscouldinterfere withtheirrescuedutiesandgetwetChloraminesampleswere takenateightlocationsapproximately3ndash4ftabovethedeckinthe poolareaoftheindoorwaterparkandacontrolsamplewastaken inanadministrativeofficeoutsidethepoolareaAnadditional sampleatthewaterfortlocationwastakenonApril14only

OnMarch202007trichloramineconcentrationswere measuredoverone8-hourshiftin4-hourincrementsandthe solublechlorineconcentrationsweremeasuredin2-and4-hour incrementsThesolublechlorineconcentrationsweremeasured overvaryingtimeperiodstoassesswhetherthehumidityinthe poolareawouldsaturatethesamplingmediaOnApril14and April24bothtrichloramineandsolublechlorinesampleswere takenovertwoconsecutive8-hourshiftsin4-hourincrementsand overa2-hourincrementbeforethepoolopenedandafteritclosed

TemperatureandRHweremonitoredalongsideeachchloramine samplinglocationDatawasrecordedeveryminuteusingaHoboreg H8ProSeriesdata-logger(OnsetComputerCorporationPocasset Massachusetts)andspotmeasurementsweretakenwithaQshyTrakTMPlusmonitor(TSIModel8554ShoreviewMinnesota)

Endotoxin Measurements

Areaairandbulkwaterendotoxinconcentrationsweremeasured becauseoflifeguardreportsofrecurringfeverbodyachesand chest-flu(feverandcoughorpneumonia)symptomsBulkwater samplesforendotoxinweretakenpoolsidefromeachwater


Assessment (Continued) filtrationsystemandtwoofthesurgetanks(childrenrsquospooland

leisureriver)onApril142007Controlsamplesweretaken fromtherestroomtapwaterAreaairsamplesforendotoxin concentrationswerecollectedthroughoutthewaterparkanda controlsamplewastakeninanadministrativeoffice

Microbial Measurements

BulkwatersamplesforLegionellaandmycobacteriawereobtained toidentifyotherpossiblecausesofrespiratorysymptomsBulk watersamplesweretakenatninelocationswithatleastone samplecollectedpoolsidefromeachwaterfiltrationsystemandtwo ofthesurgetanks(childrenrsquospoolandleisureriver)onMarch28 2007Watersamplesweretakenforfecalcoliformbacteriaatthe samelocationsonApril242007tocheckforfecalcontamination

Sulfate and Sulfite Measurements

Bulkwatersamplesweretakenpoolsideforsulfatesandsulfites fromeachfiltrationsystemonMarch282007Thesewater samplesweretakenattherequestofGWLmanagementbecause ofcertainpatronsrsquobeliefsthattheirskinrashresultedfroma preexistingldquosulfurallergyrdquo

Medical Interviews

DuringtheinitialsitevisitNIOSHphysiciansconducted confidentialmedicalinterviewswith10lifeguardsfromtheday shiftManagementselectedeightlifeguardsandNIOSHselected twoInterviewquestionsconcernedpersonalcharacteristics medicalhistoryjobdutiesandwork-relatedsymptoms

Symptom Questionnaires

BetweenMarch20andApril24exposedindividuals(lifeguards workinginsidethepoolarea)andunexposedindividuals (employeesnotworkinginsidethepoolarea)filledoutaninitial questionnaireconcerningdemographicsworkplaceinformation smokingstatusmedicalhistoryepisodesofpneumoniaorchest fluwithfeverandcoughsinceworkingatGWLandwork-related


Assessment (Continued) symptomswithintheprior4weeksUnexposedindividualsworked

inGuestServicesArcadeBearClawCafeacuteBuckhornRetailand StarbucksAllparticipationwasvoluntaryweobtainedwritten informedconsentfromtheparentsofallstudyparticipantsunder theageof18years

Lifeguardscompletedanadditionalquestionnaireatthe endoftheirworkshiftondaysthatchloramineairsampling wasconductedItcontainedquestionsrelatingtosymptoms experiencedduringtheirworkshiftthatday

Healthoutcomesofinterestincludedwork-relatedrespiratory symptoms(coughwheezingshortnessofbreathchesttightness) mucousmembraneirritation(coughsorethroateyeandnose irritation)systemicsymptoms(feverbodyaches)andskin rashesParticipantswereaskednottoreportsymptomsassociated withacoldorrespiratoryinfectionSymptomswereconsidered work-relatediftheyoccurredonthedaysoreveningsthatthe employeeworkedandimprovedondaysoffworkQuestions aboutrecurrentepisodesofpneumoniaorchestfluwithfeverand coughexperiencedatGWLwereusedtoidentifypotentialcasesof hypersensitivitypneumonitis

Statistical Analysis

StatisticalanalysiswascarriedoutwithSASversion913software (SASInstituteCaryNC)One-wayanalysisofvariancewasused tocomparethehumidityandtemperaturearithmeticmeansfor variouslocationsinthepoolareaAP value le 005 was considered statisticallysignificantAveragechloramineconcentrationswere calculatedacrosslocationusingtime-weightedmeansTocalculate time-weightedmeanssamplingresultsthatwerebelowtheLOD wereassignedavaluebydividingtheLODbythesquarerootof twoValuesbetweentheLODandLOQwerecalculatedfromthe laboratoryrsquosbestestimate

Prevalenceratioswith95confidenceintervalswerecalculatedto comparework-relatedsymptomsinthelast4weeksfortheexposed andunexposedemployeesAprevalenceratiowasconsidered statisticallysignificantifthe95confidenceintervalexcluded thenumberoneGeneralizedlinearmodelswereusedtocompare respiratorysymptomsfortheexposuregroupswhilecontrolling forsmokingstatus(currentsmokerornot)andasthmastatus

Page 0 Health Hazard Evaluation Report 2007-0163-3062

Assessment (Continued) Anemployeewasdefinedashavingasthmaifheorshehadit

currentlyitwasdiagnosedbyahealthprofessionalanditbegan beforestartingworkatGWL

Wealsocalculatedprevalenceratiostocomparework-related symptomsforlifeguardsondaysofhighandlowhoteloccupancy Generalizedestimatingequationswereusedtoaccountforpossible correlationsbetweenresponseswhenalifeguardfilledoutthe additionalquestionnaireonmorethanonedayTheanalyses involvingrespiratorysymptomswereadjustedforsmokingstatus Employeeswithasthmawereexcludedfromtheseanalyses

Results Water

WaterchemistryresultsareoutlinedinTableA1inAppendixA ParametersincludedwaterpHandfreeandcombinedchlorine concentrationsMultiplemeasurementsineachsystemweretaken toidentifypotentialareasofinadequatewatercirculationThis canbeindicatedbydifferencesinwaterchemistryreadingstaken fromthesamewatersystemMostwatersystemshadconsistent measurementshoweverdifferenceswerenotedinsomewater systemsAtthechildrenrsquospoolwatercollectedatthegeyserspray featurehadapHof78whereaswatercollectedonthewestpool edgehadapHof70Inthechildrenrsquospoolwatersystemthe geysersourcewaterisdrawnfromthefeaturersquossurgetankwhich bypassesthetreatmentsystem

Theenvironmentalhealthsystemassessmentshowedthatthe facilitydesignandindividualaquaticfeaturesmetorexceededthe statersquosstandardsWiththeexceptionoftwolowpHreadings(70 and71)onMarch20disinfectionparameterswereacceptable TheselowpHreadingswerenotsignificantwhenaveragedwith otheracceptablereadingstakenfromthesamewatersystem ThewaterchemistrytestsperformedonMarch20andduring theenvironmentalhealthassessmentonMarch28metstateand localstandards[OhioDepartmentofHealth2003]Thefree andcombinedchlorineconcentrationsrecordedintheGWL recordkeepinglogsonthedaysofsamplingarelistedinTableA2 inAppendixA


Results Ventilation (Continued) BasedontheGWLblueprintstheindoorwaterparkareais approximately80000ft2andapproximately4millionft3intotal volumeUsingthesquarefootagevolumeandtheairsupply volumetricflowratestakenfromthetestandbalancereportthe calculatedmaximumairexchangerate(withoutrecirculation) isapproximately20ACHandtheminimumairchangerate isapproximately13ACH(with33ofairrecirculated)The minimumoutdoorairflowrateisapproximately88000cfmbased ontheresultsfromthetestandbalancereportandthemaximum recirculationconditionof33duringoccupiedoperations

Industrial Hygiene

Chloramines

Two-hundredandfiveareaairsamplesweretakeninsidetheGWL poolareaSummariesofmeasurementscollectedonhighhotel occupancydays1and2(March20andApril14respectively) andthelowhoteloccupancyday(April24)areshowninTables 1and2withmoredetailedresultsinTablesA3A4andA5in AppendixATables1and2alsoindicatethepercentageofsamples thatfellbelowtheLOD(non-detectable)betweentheLODand LOQ(trace)andabovetheLOQ(quantifiable)

Table 1 Trichloramine Air Concentrations Samples of Range LOD LOQ Samples Samples Hotel Occupancy between Samples (mgm3) (microgsample) below LOD above LOQ LOD LOQ

High Occupancy Day 1 High Occupancy Day 2 Low Occupancy

16 45 38

ND ndash 066 ND ndash 106 ND ndash Trace

20 9

30

56 170 230

6 18 97

0 62 3

94 20 0

ND = Non detectable (below the LOD) Trace = Values between the LOD and LOQ

Table 2 Soluble Chlorine Air Concentrations Samples of Range LOD LOQ Samples Samples Hotel Occupancy between Samples (mgm3) (microgsample) below LOD above LOQ LOD LOQ


22a

45 39

ND ndash Trace 009 ndash 025 ND ndash ND

70 5

20

250 16

150

94 0

100

6 20 0

0 80 0

ND = Non detectable (below the LOD) Trace = Values between the LOD and LOQ a In some locations two 2-hour soluble chlorine samples were collected for every 4-hour trichloramine sample


Results (Continued) TheLODandLOQvaluesvariedgreatlyoneachsamplingday

TheLODisthelevelatwhichthecompoundofinterestcanbe detectedanddistinguishedfromtheblankresponseTheLOD isdeterminedbythevariabilityoftheresponsesofblanksand lowlevelstandardsTheLOQistheminimumlevelthatcan bereportedwithconfidenceTheLOQisdeterminedeitheras 333timestheLODorthelevelatwhichtheminimumrecovery formediaspikesis75whicheverishigherTracevaluesor valuesbetweentheLODandLOQindicatesampleswherethe compoundwasdetectedhoweverlevelsweresolowthatthey couldnotbequantifiedreliably

Onhighoccupancyday138chloraminesamplesweretaken (16trichloramineand22solublechlorinesamples)Onthisday themajority(94)oftrichloraminesampleswasquantifiable andthecalculatedmeanwas044mgm3Meanconcentrations werecalculatedateachsamplinglocationThehighestmean trichloramineconcentrationbylocation(057mgm3)andthe overallhighesttrichloramineconcentrationcollected(066mgm3) wereattheleisureriverattractionwhichcontainswaterslides sprayfeaturesandsplashpoolsThemajority(94)ofsoluble chlorineconcentrationssampledonthisdayfellbelowtheLOD Thereforewedidnotcalculateameanvalueforsolublechlorine compoundsonthisdaySeeTablesA3ndashA5inAppendixAfor completechloramineresults

Onhighoccupancyday290chloraminesamplesweretaken(45 trichloramineand45solublechlorinesamples)Oftrichloramine samplescollectedonthisday82haddetectableconcentrations howeveronly20ofallsampleswerequantifiableAlthoughthis datahadmanynon-quantifiableconcentrationsitalsocontained thehighesttrichloramineconcentrationfound(106mgm3)of allsamplescollectedThishighconcentrationwasobtainedatthe leisureriverwhichalsohadthehighestmeanconcentrationby location(080mgm3)Themajority(80)ofsolublechlorine concentrationsonthisdaywasquantifiablewithamaximum concentrationof025mgm3andameansolublechlorine concentrationof017mgm3Nomajordifferenceswereobserved acrosslocationsforsolublechlorine


Results (Continued) Onthelowoccupancyday77chloraminesampleswerecollected

(38trichloramineand39solublechlorinesamples)Allofthe solublechlorinesamplescontainednon-detectableconcentrations Onlyonetrichloraminesamplecontainedadetectable concentrationwhichwasreportedatatracelevelTherefore meansfortrichloramineandsolublechlorinesampleswerenot calculated

Endotoxin

AirandwaterendotoxinlevelsareshowninTablesA6andA7in AppendixAAirendotoxinconcentrationsinthepoolarearanged from18to84EUm3withameanconcentrationof45EUm3 Theseairendotoxinlevelswereabout10to40timeshigherthan levelstakeninanadministrativeofficeoutsidethepoolarea Thelocationswiththehighestairconcentrationswerethewave pool(84EUm3)andleisureriver(67EUm3)Thehighestwater endotoxinconcentrationswerealsofoundinthewavepool(61 EUmL)andleisureriver(77EUmL)Endotoxinlevelswere similarinthewatersystemswheresamplesweretakenfromboth thesurgetanksandsurfacewaterEndotoxinconcentrationsin watersamplestakenfromthehottubswereverylowandinsome casesmeasuredlowerthanthosefoundintapwaterwhichwe sampledforcomparison

Air Temperature and Relative Humidity

AverageairtemperatureandRHresultsareshowninTableA8 inAppendixAAirtemperatureaveragestakenacrosslocations rangedbetween82ordmFand89ordmFwiththehighesttemperatures locatedatthetopoftheslidetowerRHaveragesacrosslocations rangedfrom43to69withhighobservationsnotedatthe towelrackandneartheleisureriverRHandtemperaturetaken atdecklevel(excludesmeasurementstakenatthetopoftower) differedsignificantlyacrosslocations(Plt001)Theaverage RHvariedbyabout37acrosslocationsatdecklevelonhigh occupancyday1anditdifferedbyover30acrosslocationsat decklevelonhighoccupancyday2andthelowoccupancyday

Microbials

NoLegionellafecalcoliformbacteriaormycobacteriawerefound inanyofthewatersamples


Results Sulfates and Sulfites(Continued) Sulfateconcentrationsinwatersamplesrangedfrom940mgLto 1600mgLNosulfitesweredetectedTheLODforsulfitewas05 mgL

Medical Interviews

The10interviewedlifeguardsallreportedacoughthatthey associatedwithworkandthatimprovedondaysoffworkThree employeeshadasthmabeforeworkingatGWLandonereported thatasthmasymptomshadworsenedsinceworkingatGWLTwo employeesreportedincidentsofvomitingcausedbyexcessive coughingsevenreportedeyeirritationthreereportednose irritationthreereportedskinrashandoneemployeereportedtwo episodesofflu-likesymptomswithcoughandfeverOneemployee reportedintermittentblurryandhalovisioninoneeyeWhenthe visualsymptomsoccurredtheyalwaysstartedafterthebeginning oftheshiftandtypicallyresolvedwithinacouplehoursofleaving workTheemployeeusedonecontactlensanddidnotexperience blurryvisionintheeyewiththelensIngeneralemployees reportedthattheirsymptomswereworsewhenthebatherloadwas highandwhentheoutsidetemperaturewascolder

Initial Questionnaire

Seventyof103exposedlifeguards(68)and74of99(75) employeesworkingoutsidetheindoorpoolareacompletedthe initialquestionnairewithinthetimeperiodMarch202007 ndashApril22007Dataanalysiswasrestrictedtoquestionnaires receivedMarch202007ndashApril22007becausethistimeperiod wascolderandmorerepresentativeoftheoutdoortemperature wheninitialsymptomswerereportedThisdaterestriction excludeddatafrom12exposedindividuals

DemographiccharacteristicsaresummarizedinTable3Exposed individualswereyoungerthanunexposedindividualsTheywere similarintermsofmeanworkhoursperweekpersonalhistoryof asthmadiagnosedbyadoctororotherhealthprofessionalpriorto employmentatGWLandpersonalhistoryofhayfeverorother non-drugallergies


Results (Continued)

Table 3 Demographic Characteristics

Characteristic Exposed (N = 69 ndash 70)

Unexposed (N = 74)

Age ndash average (range) 20 (16 ndash 50) 31 (15 ndash 61)

Male ndash no () 37 (53) 24 (32)

Months in present job class ndash average 28 41

Work hours per week ndash average 318 326

Smoking current ndash no () 16 (23) 12 (16)

History of

Asthma before GWL ndash no () 12 (17) 9 (12)

Hay fever or other non-drug allergies ndash no () 24 (34) 29 (39)

Eczema or atopic dermatitis ndash no () 2 (3) 12 (16)

Exposedindividualsweresignificantlymorelikelythanunexposed individualstoreportwork-relatedrespiratorysymptomsfever bodyachesandeyeandnoseirritationduringthe4weekspriorto surveycompletionasshowninTable4

Table 4 Work-Related Symptomsa Between Exposure Groups Exposed Unexposed Prevalence Ratio Symptom (N = 68 ndash 70) (N = 74) (95 CIb)

no of employees ()

Sore throat 22 (32) 2 (3) 1180 (288 ndash 4831)

Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c

Eye irritation 51 (73) 6 (8) 899 (412 ndash 1961)

Fever 14 (21) 2 (3) 762 (180 ndash 3230) Shortness of 26 (38) 4 (5) 670 (247 ndash 1820) c

breath

Chest tightness 19 (28) 3 (4) 667 (208 ndash 2135) c

Body aches 20 (29) 4 (5) 529 (190 ndash 1470)

Nose irritation 33 (48) 10 (14) 354 (189 ndash 662) a Symptoms experienced on the days or evenings that the employee worked within the prior 4 weeks and improving on days off work surveyed March 20 2007 ndash April 2 2007b CI denotes confidence interval c Adjusted for smoking and asthma status


Results (Continued) Exposedemployeeswerealso58timesmorelikelytoreportan

episodeofchestflu(definedasfeverandcough)orpneumonia sinceemploymentatGWLAmongthosewhoreportedatleast oneepisodetheaveragenumberofepisodeswas23

Allindividualswhoreportedahistoryofasthmadiagnosedbya doctororhealthprofessionalhadasthmabeforeworkingatthe GWLSixofthe10exposedindividualswhostillhadasthma reportedthattheirasthmaseemedworsewhenatworkwhereas noneofthesevenunexposedindividualswhostillhadasthma reportedthattheirasthmawasworseatwork

Theprevalenceofreportedskinrashwithintheprior4weeks was50timeshigherforexposedindividualsthanunexposed individuals(Plt001)Ofexposedindividuals41(2970) reportedhavingaskinrashcomparedto8(673)ofunexposed individualsAmongthelifeguardswhoreportedarashthemost commonlyaffectedareaswereleg(79)arms(34)andtrunk (28)

Daily Symptom Questionnaire

Fourteenof17exposedlifeguardscompletedthedailysymptom questionnaireduringthemorningshiftonhighoccupancyday1 2943duringthemorningandeveningshiftsonhighoccupancy day2and2733duringthemorningandeveningshiftsonthe lowoccupancydayforaparticipationrateof7667and82 respectivelyMostlifeguardsworkingonthehighoccupancydays reportedwork-relatedcoughandeyeirritationasshowninTable 5Nonereportedblurryfoggyorhalovisiononthelowoccupancy dayIncontrastonhighoccupancyday2929(31)reported blurryorfoggyvision


Results (Continued)

Table 5 Daily Work-related Symptomsa Among Exposed Lifeguards

Symptom High Occupancy Day

1 (N = 14)

High Occupancy Day 2

(N = 29)

Low Occupancy Day

(N = 27) no of employees ()

Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)

Wheezing 1 (7) 7 (24) 2 (7) Shortness of breath 2 (14) 6 (21) 4 (15)

Chest tightness 3 (21) 5 (17) 0

Sore throat 6 (43) 2 (7) 4 (15) Blurry or foggy vision mdashb 9 (31) 0

Blue-grey vision mdash b 3 (10) 1 (4)

Halo vision mdash b 3 (10) 0 a Symptoms experienced at work starting at beginning middle or end of shift b This information was not collected on the initial version of the questionnaire and therefore is missing for date 32007

Datafromhighoccupancydays1and2wascombinedtocalculate symptomprevalenceratioscomparinghighversuslowhotel occupancydaysWorkingonhighhoteloccupancydayswas associatedwithasignificantlyincreasedriskofexperiencingworkshyrelatedcoughandeyeirritationasshowninTable6

Table 6 Work-related Symptoms a Among Exposed Lifeguards On High versus Low Hotel Occupancy Days

Prevalence Ratio Symptom (95 CIb) Cough 223 (110 ndash 452) c

Eye irritation 196 (122 ndash 317)

Wheeze 243 (050 ndash 1187) c

Shortness of breath 105 (030 ndash 369) c

Nose irritation 216 (083 ndash 559)

Sore throat 127 (046 ndash 351)

Chest tightness undefinedd

a Symptoms experienced at work starting at beginning middle or end of shift b CI denotes confidence interval c Adjusted for smoking status excludes lifeguards having asthma d Undefined indicates that prevalence ratios could not be calculated because no one reported symptoms on the low hotel occupancy day


Results (Continued) Nosignificantassociationexistedforblue-greyvisionand

prevalenceratioscouldnotbedefinedforblurryfoggyorhalo visionbecausenoonereportedthosesymptomsonthelow occupancyday

disCussion TheGWLindoorwaterparkisacomplexpoolenvironmentdueto severalfactors(1)thesizeofthecontainedarea(about80000ft2) (2)highwatervolume(415000gallons)andwatersurfaceareaand (3)theamountofwateraerosolizationcausedbysprayfeatures waterslidesetcInadditiontheindoorpoolenvironmentis affectedbyotherfactorsincludingwaterqualitydisinfectantsand theirby-productsnumberofbathersenvironmentalconditions (airandwatertemperatureRHetc)andairhandlingunitdesign andfunctionAlsoindividualfactorsincludingthetimespentby employeesandpatronsinthepoolareaandpersonalsusceptibility toairbornecontaminants(egpreexistingasthmayoungchildren withimmaturerespiratorysystems)canaffecttheseverityof symptomscausedbyDBPsandothercontaminantsControlof symptomscausedbyDBPsandothercontaminantsrequiresa multidisciplinaryapproachincludingairhandlingunitdesign waterchemistrycontrolslimitingaerosolizingsprayfeaturesand poolproceduresandpolicies

Water Water Mixing and Circulation

Thewaterchemistrydifferencesinsomeofthewatersystems canbeattributedtoincompletemixingoftreatedwateroruseof partiallydisinfectedwaterInvestigationintothedifferencesin thewaterchemistryresultsbetweenthepoolandsprayfeatures ofthesamewatersystemshowedthatallthesprayfeaturesdraw waterdirectlyfromthesurgetanksBecausesurgetankwateris thestartingpointofthewaterfiltrationcycleitcouldcontain morecontaminantsthanwatertakenattheendofthefiltration cycleEventhoughthesprayfeaturescontributeaminuteamount ofwatertothepoolanywatercontaminantspresentcouldbe aerosolized

Completeandroutinewaterreplacementinbothhottubsmay havecontributedtotheirlowwaterendotoxinconcentrations Howeverthispracticemaynotbefeasibleforlargerbodiesof


disCussion (Continued) wateranddilutionisrecommendedDilutionisamethodof

addingfreshwatertodecreasetheconcentrationofDBPsnot removedbythewatertreatmentsystemTheWHOrecommends adilutionrateof30litersoffreshwaterperbathertodecreasethe concentrationofbather-generatedcontaminants[WHO2006] Adjustmentsoftheseratesneedtoaccountforevaporationrates splash-outelevatedcombinedchlorineandairrecirculationmode CurrentlyGWLdoesnotrecordtheamountofwaterusedto refreshthesystembutislookingatoptionstomeasureandbetter controltheamountofwaterthatisremovedandreplaced

Water Chemistry

Understandingmonitoringandcontrollingwaterchemistryisan importantfactorthatcanlimittheformationofDBPsandtheir migrationfromwaterintotheairSeveraloutbreakinvestigations ofrespiratoryandirritationsymptomsatindoorswimmingpools haveassociatedsymptomswithimproperwaterchemistrycontrol specificallyabnormallevelsofpHandcombinedchlorine[Bowen 2007Kaydos-Daniels2007Safranek2007]Thesestudiesshowed thatthecombinedchlorinelevelsinwaterforthemajorityof outbreakswereelevatedonthedayssymptomswerereportedOne Nebraskapoolhadacombinedchlorineconcentrationofatleast eighttimesthestatersquosmaximumallowablelevelwhensymptoms werereported[Safranek2007]

About80(1417)ofthepoolsurfacewatersamplesandnoneof thehottubsurfacewatermeasuredonMarch202007exceeded theNationalSwimmingPoolFoundationrsquosrecommended maximumcombinedchlorineThehighestcombinedchlorine levelsmeasured04ppmwhichwasnotexceptionallyhigh Howeverthecombinedchlorinevaluefoundinwaterdoesnot takeintoaccounthowventilationsystemsandairmovementaffect thechloraminelevelsintheairAnindoorpoolwithnormal combinedchlorinelevelscanhavehighairtrichloraminelevels ifthereisinsufficientintakeoffreshair[StottmeisterandVoigt 2006]Converselyanindoorpoolwithrelativelyhighcombined chlorinelevelscanhavenormalairtrichloraminelevelsifthe ventilationsystemishighlyefficientThereforeinterpretationof combinedchlorineresultsneedstotakeintoaccountventilation efficacy

ThestateofOhiodoesnothaveacombinedchlorinestandard howeverseveralotherconsensusguidelinesandstandardscanbe


disCussion (Continued) usedtocomparethecombinedchlorineconcentrationsmeasured

attheGWL(1)TheCertifiedPool-SpaOperatorHandbook [Ford2007](2)otherstatecodesand(3)theGermanDIN Standard19643[DIN196431997]TheNationalSwimming PoolFoundationrecommendsamaximumcombinedchlorine concentrationof02ppmforpoolsand05ppmforspasand hottubs[Ford2007]Theotherstandardsmentionedhave similarlimitstheGermanDINStandard19643listsamaximum combinedchlorineconcentrationof02ppm[Simonic2003]and severalstateshavecoderegulationsrangingfrom02ppmto10 ppm

Ventilation

Theguidelinesandstandardsdiscussedbelowweredevelopedto provideadequateventilationforstandardstillwater-typepools similartowhatonemightencounteratahotelorothersmall recreationalfacilityTheGWLdesignandactiveaquaticfeatures differgreatlyfromstandardpoolsthereforetheventilation guidelinescurrentlyinplaceforpoolfacilitiesmaynotbesuitable forthisenvironment

Comparison of Ventilation Rates with Consensus Standards and Guidelines

Anumberofdifferentconsensusstandardsandguidelines canbeusedtocomparetheventilationratesusedatthe GWLindoorwaterpark(1)TheASHRAEandtheANSI publicationANSIASHRAEStandard621-2007Ventilation for Acceptable Indoor Air Quality[ASHRAE2007a](2)The2006 WorldHealthOrganizationGuidelinesforSafeRecreational WaterEnvironmentsVolume2Swimmingpoolsandsimilar environments[WHO2006]and(3)The2007ASHRAE Handbook-HVACApplications[ASHRAE2007b]These standardsareperiodicallyupdatedbasedonthelatestscientific researchWhiletheventilationratesusedattheGWLmaymeet onestandardtheymaynotmeetotherguidelinesorstandards

ThestateofOhioincorporatestheoutdoorairventilation requirementsfromANSIASHRAEStandard62Ventilation for Acceptable Indoor Air QualityintotheOhioBuildingCodeand appliesthisstandardtoventilationofindoorpoolfacilitiesThe standardrecommendsminimumventilationratesforacceptable


disCussion (Continued) indoorairqualityofenclosedspacesAccordingtothisstandarda

minimumof24literssecondpermeter2(048cfmft2)ofoutdoor airisrecommendedtoventilatepoolanddeckareasofindoorpool facilitiesForGWLthisstandardcorrespondstoapproximately 40000cfmofoutdoorairBasedondesigninformationGWL exceedsthisrequirementbyprovidingaminimumof88000cfm duringmaximumrecirculationoperationThisANSIASHRAE standardventilationrateisbasedontheamountofairbelieved tobesufficienttodilutebuildingandoccupantgenerated contaminantsdowntoanacceptablelevelHoweverrecent researchonairqualityinindoorpoolshasshownthatmany poolsmayhavecomplaintsdespitemeetingtypicalventilation guidelinesTheWHOrecentlyupdatedtheirguidelinesforindoor poolenvironmentstorecommendaminimumof10litersoffresh airpersecondpermeter2ofwatersurfacearea(2cfmft2)[WHO 2006]

The2007ASHRAEHandbook-HVACApplicationsrecommends airexchangeratesbetween4and8ACHforindoorpoolfacilities dependingontheuseofthepoolThenumberofACHisthe ratioofairflowventilationtoroomvolumeGWLprovides 13to20ACHandthereforedoesnotmeetthisASHRAE guidelineTheuseofACHasaperformancestandardfor ventilationsystemshasbeeninplaceformanyyearsHowever itisnotalwaysseenasagoodmeasureofacceptableventilation forallapplicationsAtGWLalargemajorityofthefacilityair volumeisconcentratedinahighbayareaprimarilycomprisedof unoccupiedspaceThereforetherelianceonmeetingaminimum numberofACHmaynotbeapplicableforthissettingHowever theintroductionofmoreoutdoorairmaybenecessaryatGWLto effectivelydilutetheincreasedcontaminantloadduetothelarge numberofwatersprayfeaturesandhighbatherloads

Air Distribution Design

Thedesignoftheair-distributionsystemmaybemoreimportant thanairexchangerateSeveralcriterianeedtobemettoensure comfortwhilestillmaintainingacceptableairqualityFor instancewhilesomeairflowisrequiredacrossthepoolanddeck surfacestheamountofairflowshouldbeminimizedtoprevent draftsonswimmersandtoreduceevaporation[XieandCooper 2006]GeneralASHRAEguidancerecommendspositioning exhaustairinletstomaximizecaptureeffectivenessandminimize recirculationofchloramines[ASHRAE2007b]Chloramine


disCussion (Continued) compoundsareheavierthanairandaremorelikelytoconcentrate

closertothepoolsurfaceanddecklevelandsomeairflowis requiredtomovethemtowardsanairreturn

Adequateairflowratesatdeckandpoolsurfacesarenecessaryto movethecontaminantsfromthepooltothereturnductssothey canbeexhaustedfromthebuildingOneofthemajorchallenges withtheairdistributionsystematGWListheplacementofsupply andreturnairdiffusersatheightsof30ndash80ftabovethepooldeck inunoccupiedareasThismaycreateshortcircuitingofairflow fromthesuppliestothereturnsinthehighbayareaTheheight ofthesupplydiffusersabovethedeckalsohinderstheabilityof theventilationsystemtoprovideadequateairmovementatthe pooldeckareaAdditionallytheplacementoffourlargeairreturn ductsapproximately60ndash80ftabovethepooldeckmakesthem poorlypositionedtocaptureandremovecontaminantssuch aschloramineswhichconcentrateatdecklevelanddoesnot promotegoodairmovementintheareasofhighestoccupancy Theuseofcomputer-basedsimulationsmayprovidesomeinsight intothedesignandeffectofchangestotheairdistributionsystem CFDmodelingisananalyticaltoolthatcanprovideadetailed visualdescriptionofthefluidflowheattransferandcontaminant transportBysolvingthefundamentalequationsofconservation ofmassmomentumandenergyaCFDmodelcanprovide informationincludingvelocityfieldstemperaturedistribution andchemicalspeciesconcentrationwithinaregionofinterest CFDcouldbeusedtoanalyzeexistingairflowpatternsandtogain insightintotheeffectofnewdistributiondesigns

WeareawarethatGWLhaschangedtheairdistributionsystemto attempttoaddressconcernswithstagnantairatdecklevelsThese changesincludedloweringthreehighreturnairventstothedeck levelandinstallinghighthrowairdiffusersinselectedareasThe airhandingunitsrsquovolumeofairflowwasincreasedandductwork changesweremadetoincreaseairmovementtothefrontandback areasofthewaterparkGWLestimatesthatafterthesechanges weremade33ofthereturnairistakenfromthehighbayarea and67oftheairispulledfromthelowerreturnairintakes[Zajo 2008b]Thesechangeswerenotevaluatedasapartofthisstudy PriortothesechangesGWLrsquosventilationcontractorperformed qualitativeairflowtesting(usingcommercialfogmachines)inthe poolareatoobserveairflowpatternsNIOSHinvestigatorswere notpresentwhenthefogtestingoccurredandwedidnotreview theresults


disCussion (Continued) Air Temperature and Relative Humidity

PocketsofhigherlevelsofRHwereconsistentlyseenthroughout eachsamplingperiodThevariationsweresignificant(P lt001) andmayrepresentpoorairmovementatthedeckleveland potentialbuild-upofcontaminantsPocketsofhighcontaminant concentrationscanoccuratlocationswhereflowisinsufficient tomoveairtotheexhaustductswhereaerosolizationfromspray featuresoccursorwherestructuresmayobstructairmovement

Chloramines and Associated Symptoms

ThetrichloraminelevelsmeasuredattheGWLweresimilarto levelsfoundinotherindoorswimmingpoolstudiesandsomewere atlevelsreportedtocausemucousmembraneirritation[Heryetal 1995Massinetal1998Thickettetal2002Jacobsetal2007] ThesymptomsreportedbyGWLlifeguardsareconsistentwith thoseassociatedwithtrichloramineexposureandwerehigheron dayswhenhoteloccupancywashighHoteloccupancywasused asaproxyforbatherloadandincreasedbatherloadhasbeen significantlyassociatedwithanincreaseintrichloraminelevels [Jacobsetal2007]Twentyfivepercent(416)ofthetrichloramine samplestakenonhighoccupancyday1and20(945)takenon highoccupancyday2exceededaconcentrationof05mgm3the levelatwhichirritationsymptomshavebeendocumented[Heryet al1995]IntheHeryetalstudynoonereportedsymptomsuntil thechloramineconcentrationreached05mgm3andeveryone reportedsymptomswhenthelevelsreached07mgm3Inanother studyinvolving334lifeguardsand63indoorpoolstheprevalence ofmucousmembraneirritationamonglifeguardsexposedto trichloraminelevelsabove05mgm3was86foreyeirritation 61noseirritation29throatirritationand42drycough [Massinetal1998]Jacobsetalmeasuredtrichloraminelevelsat sixindoorswimmingfacilitiesandfoundanelevatedprevalenceof respiratorysymptomsinswimmingpoolworkersTheymeasureda meantrichloramineconcentrationof056mgm3withthehighest concentrationreaching134mgm3Generalrespiratorysymptoms weresignificantlyhigherinpoolemployeescomparedtotheDutch populationsample(oddsratiorangedfrom14to72)[Jacobsetal 2007]

Basedonconcentration-responsedatainmiceGagnaire etal recommendedaSTELof15mgm3andaTWAof05mgm3for


disCussion (Continued) trichloramine[Gagnaireetal1994]ATWAexposurereferstothe

averageairborneconcentrationofasubstanceduringanormal8- to10-hourworkdayAlthoughproposedstandardsandpaststudies indicatethatacomfortlevelforindoorpoolareaswouldbetokeep trichloramineconcentrationsbelow05mgm3therehavebeen someconcernsthatthislevelmaynotbelowenoughtoprevent symptoms[Massinetal1998]Astudycomparingtheprevalence ofhealthcomplaintsbetweenteenageswimmersandsoccer playersshowedasignificantincreaseinrespiratorycomplaintsat chloramineconcentrationsof037mgm3orgreater[Levesque etal2006]TheWHOrecommendsusinganairtrichloramine concentrationof05mgm3asaprovisionalvaluealthoughit statesthatmoreresearchisneededtoinvestigatehealtheffectsin peoplewhousethepoolforextendedperiodsoftimeandtherole oftrichloramineinpossiblycausingorexacerbatingasthma[WHO 2006]

Properairmovementanddistributionplayakeyroleinreducing chloramineconcentrationsandhealtheffectsIn1983an occupationalmedicinephysicianreportedaswimmerwho developedcoughingandwheezingonlywhenvisitingapool equippedwithanautomaticallycontrolledheatreclamationsystem [Penny1983]Symptomswereworseinthewintermonthswhen theheatreclamationsystemrecirculatedahigheramountofairto conserveenergyThepatienthadnorespiratorysymptomswhen hevisitedanolderpoolwithasimpleairextractorSpirometry demonstrateda24to33dropinforcedexpiratoryvolumein 1secondafterswimminginthenewpoolcomparedtoa6drop inforcedexpiratoryvolumein1secondafterswimminginthe olderpoolThephysiciansuspectedthattrichloraminecausedthe respiratorysymptomshowevernoacceptedmethodformeasuring trichloramineintheairwasavailableatthattime

Recentstudieshaveraisedquestionsaboutwhetherinhalation ofDBPsmaycauseorexacerbateexistingasthmaAstudyoftwo lifeguardsandaswimminginstructorshowedthatswimmingpool asthmacanoccurinworkerswhoareexposedtochloraminesThe researchersgeneratedtrichloraminesat05mgm3inachallenge chamberandexposedtheparticipantstoaseriesof10-minute exposuresfollowedbyspirometryResultsshowedadecreasein pulmonaryfunction[Thickettetal2002]Additionallynew researchindicatesthattheremaybeothervolatileDBPswith potentiallyirritantpropertiesinindoorpoolenvironments[Li 2007]


disCussion Waterattractionsthatcreatesurfacewaterdisturbancescan (Continued) increaseaerationofwatercontaminantsWefoundhigher concentrationsoftrichloramineinareasaroundtheleisureriver wherethereiscontinuouswatermovementandsplashingThis attractioncontainsahighwater-to-airsurfaceareainconstant motionwhichcanaccelerateevaporationAstudyconductedat anindoorswimmingpooldemonstratedthattheoperationof awaterslideincreasedthenumberofrespirableparticlesby23 foldandthatnumberincreasedby52foldwithfullwaterfeature use[Roseetal1998]Otherstudieshavelookedatchloramine concentrationdifferencesbetweenindoorleisurepools(pools containingwater-disturbingfeatureslikeslides)andstillwater poolsInonestudymeantrichloraminelevelswere024mgm3 atstillwaterpoolsand067mgm3atleisurepools[Massinetal 1998]Heryetalalsoreportedthatairchloramineconcentrations werehigherinleisurepoolsduetotheinfluenceofslidesbubbling bathswavesandotherwateractivities[Heryetal1995]

Systemic Symptoms

Lifeguardsweremorelikelytoreportwork-relatedcough feverandbodyachesaswellaschestfluwithfeverandcough orpneumoniasinceemploymentatGWLThesesymptoms togetherareconsistentwithhypersensitivitypneumonitis Hypersensitivitypneumonitisisarareconditioncausedbyinhaling foreignsubstancesThesesubstancescausethelungstobecome inflamedInindoorpoolenvironmentsthisconditioncanbe causedbyinhalationofbioaerosolssuchasendotoxinTheair endotoxinlevelsmeasuredatGWLwereseveraltimeshigherthan backgroundlevelsandexceededtheproposedACGIHRLVfor endotoxinexposure(seeAppendixC)Theaverageairendotoxin concentrationfoundatGWL(45EUm3)wascomparabletothe averageconcentrationsmeasuredduringsequentialoutbreaksof hypersensitivitypneumonitisatanindoorswimmingpoolwith watersprayfeaturesndash76EUm3duringthefirstoutbreakand28 EUm3duringthesecondoutbreak[Roseetal1998]

Apriorstudyoflifeguardsconcludedthathypersensitivity pneumonitiswasassociatedwithendotoxin-containingrespirable bioaerosolsgeneratedbywatersprayfeaturesFulluseofthewater featuresatthatpoolfacilityresultedina35to8foldincrease inmeanairendotoxinconcentrations[Roseetal1998]Water collectedfromthesprayfeaturesatthepoolgrewGram-negative bacteriawhichwaspresumedtobethesourceofendotoxinAt


disCussion (Continued) thisindoorswimmingpooleliminatingbacteriafoundinside

thesprayfeatureswaskeytodecreasingairendotoxinlevelsand symptoms

Skin Rash

GWLpatronsraisedquestionswhetherallergiestosulfa medicationswouldcausethemtohaveallergicskinreactions whenexposedtowatercontainingsulfuricacidSulfuricacid canbreakdowntosulfatesHoweveritishighlyunlikelythat theskinrashreportedbythelifeguardsisduetoasulfateallergy Sulfateallergiesareextremelyrareandsulfatesaresocommon thatmostpeoplehavebeenexposedtothemearlyinlife(ie sulfatesarecontainedinmostpersonalhygieneproducts) Additionallythemostcommonldquosulfurallergyrdquoassociatedwith medicationisduetosulfonamidewhichischemicallydistinct fromsulfates[Strometal2003]

WedidnottestforPseudomonasbacteriabecausethereported skinrashesdidnothavethetypicalcharacteristicoffolliculitisor Pseudomonasinfection

Themostcommonareasofskinrashreportedamongthe lifeguardsinvolvedthelegarmandtrunkTheseareasare mostfrequentlyexposedtoldquowetworkrdquowheretheskinisin waterPossibleoccupationalskinirritantsincludeheatwater andchlorinecompoundsSeverallifeguardsreportedarash betweenthethighsandintheabdominalskinfoldstheseareas tendtoremainwarmandmoistWatercanalsobeanirritant withchronicexposureandwater-inducedcontactdermatitis amongwetworkerssuchashairdressershospitalcleaners hydrotherapistsandbartendersiswelldocumentedinthe occupationaldermatologyliterature[Tsai1999Lazarov2005 Pardo2007]GWLlifeguardsrotatethroughseveralstations andattimesstandimmersedinwateruptowaistlevelto catchbatherstubesexitingfromthewaterslidesOftentimes theirbathingsuitsremainwetthroughoutanentireshiftIn additiontowaterexposurelifeguardsareexposedtochlorine compoundsinthewaterTherehavebeenafewcasereports ofcontactdermatitisassociatedwithswimminginchlorinated poolwater[Neering1977Sasseville1999]Howeverfewformal epidemiologicalstudiesexistandtheprecisemechanismhas notbeenelucidatedInarecentcross-sectionalstudyofchildren swimmingineitherchlorinatedorbrominatedpools4ndash8


disCussion (Continued) ofrespondentsdevelopedaskinrashwithin24hoursofpooluse

[Kelsall2001]Thesecasereportsandstudiessuggestthatseveral environmentalexposuresinsidetheindoorpoolareaincluding heatwaterandchlorinecompoundsallcancontributetothe higherrateofskinrashobservedamongthelifeguards

Visual Symptoms

Severallifeguardsreportedblurryblue-greyandorhalovision whileatworkAllreportedthatthevisualchangesweremostsevere duringthecoldwintermonthsWhileblurryvisioncouldbea reflectionofeyeirritationhalovisionismuchmoreunusualA varietyofaminecompoundshavebeenreportedtocausesimilar visualsymptomsForexampleaNIOSHinvestigationofblurry haloandblue-greyvisionatalabelprintingfacilitylinkedthe symptomswithexposuretoatertiaryaminecompoundInthat investigationcornealopacitywasthecauseofthesymptomsand appearedtobeduetodirectdepositionoftheaminecompound ontothecornea[Pageetal2003]Weofferedtohavethesame ophthalmologistwhoperformedtheeyeexamsinthelabelprinting healthhazardevaluationexaminelifeguardswithblurryorhalo visiontodetermineiftheyhadcornealopacityHoweveratthe timethequestionnaireswereadministeredtheenvironmental conditionsweremuchdifferentfromwhenvisualsymptoms reportedlypeakedAsaresultwemaynothavecapturedvisual symptomsduringatimeofpeaktrichloramineexposureandno lifeguardsreportedthesymptomswhentheophthalmologistwas availableInadditiontrichloraminediffersfromthetertiaryamine intheprevioushealthhazardevaluationbecausetrichloramineis inorganicandinsolubleinwater

Limitations

Duetoconcernthatthesamplingequipmentwouldinterfere withthelifeguardsrsquorescuedutiesandgetwetwedidnotmeasure personalexposurestochloraminesandendotoxinThislimited ourabilitytoevaluateanypossibleassociationbetweenchloramine concentrationsandreportedsymptomsAlsothedraftNIOSH chloraminesamplingandanalyticalmethodisstillindevelopment BecauseofthewidedifferencesintheLODsandLOQsforeach dayofsamplingwecouldnotcomparethedataacrossallsampling daysConcentrationsthatwereconsideredabovetheLOQone daymayhavebeenbelowtheLODonanotherdayTherefore


disCussion (Continued) observationscouldonlybemadewithdatafromwithinasampling

day

Outdoorenvironmentalconditionssignificantlydifferedbetween theperiodofpeakhealthcomplaints(JanuaryandFebruary) andthedaysthatNIOSHsamplingoccurredTheoutdoor temperatureaveraged35ordmFinJanuaryand20ordmFinFebruary Whenoutdoortemperaturesarebelow40ordmFtheairhandling systemstartsrecirculatingindoorairIncontrasttheoutdoor temperatureremainedabove40ordmFduringoursamplingperiods inMarch(monthaverage49ordmF)andApril(monthaverage52ordmF) BecauseindoorairwasnotrecirculatedduringthedatesofNIOSH samplingthetrichloramineandsolublechlorinelevelsmeasured inthisstudymaynotrepresenttheconcentrationspresentattime ofinitialreportsofsymptomsAlsobecauselifeguardsreported thattheirsymptomshadimprovedsignificantlywiththewarmer weatherthesymptomdatacapturedduringthisinvestigationmay notrepresentwhatthelifeguardsmighthaveexperiencedduring thecoldermonthswhenindoorairwasrecirculated

Alimitationoftheventilationassessmentwasthedifficulty intakingairflowmeasurementsStandardairflowevaluation techniquessuchastheuseofsmokevisualizationandtracergas testingweredifficultgiventhecomplexityandlargesizeofthe waterparkInsteadairhandlingsystemdesignswerereviewedto identifywaystoincreaseairmovementatthedecklevel

EnvironmentalandproceduralchangesmadefromJanuaryto MarchbyGWLinresponsetopatronhealthconcernscould havecontributedtoreducingaircontaminantconcentrationson thedayswesampledcomparedtowhenthesymptomswerefirst reportedAlsothenumberofbathersmayhavevariedfromwhen reportedsymptomspeaked(JanuaryFebruary)andoursampling days

Aroundthetimeofsurveycompletionthemediareported ontheoccurrenceofrespiratoryandskinsymptomsatGWL Becauseoftheheightenedawarenessrecallbiasmayhavebeen introducedintotheinitialquestionnaire(lifeguardsmayhave beenmoreinclinedtorecallsymptomsthanemployeesworking outsidethewaterparkarea)Alsoasthmaticsmaybemorelikely totakeupswimminginsteadofothersportsbecauseswimming isconsideredasportthatislesslikelytocauseexercise-induced asthmaThereforeswimmersmaybemorelikelytohaveasthma


disCussion (Continued) thanpeoplewhoparticipateinothersportsHowevercomparison

ofwork-relatedsymptomsamonglifeguardsondifferentdates shouldminimizethispotentialbiasandthecompletionofthe dailysymptomquestionnaireimmediatelyattheendoftheirshift shouldminimizerecallbias

Becauseonly68oflifeguardsfilledouttheinitialquestionnaire participationbiasmayhaveoccurredInadditionbecauseseveral lifeguardswerereportedtohavequitwithinthestudyperioddue towork-relatedsymptomsourresultsmayunderestimatethe prevalenceofsymptoms

ConClusions BasedonourreviewoftheventilationsystemRHand trichloraminemeasurementstheventilationsystematthetimeof ourevaluationmaynotbeprovidingsufficientairmovementand distributiontoallowadequatecaptureandremovalofchloramines atthepoolsurfaceanddecklevelsVentilationdesignconcerns includetheplacementofairsupplydiffusersandreturnairinlets atheightsof30ndash80ftabovedecklevelmakingitdifficultto providesufficientairmovementatthepoolsurfaceanddecklevels andcreatingthepotentialforshortcircuitingofsupplyairtothe exhaustductsAlsorecirculatingairduringtimesofhighbather loadmayincreaseconcentrationsofcontaminantsintheairThe factthatthefacilityrsquosoverallairexchangerateismuchlowerthan recommendedbyASHRAEisalsoaconcern

Trichloramineconcentrationsmeasuredweresimilartolevels foundinotherindoorswimmingpoolstudiesandsomewereat levelsreportedtocauseirritationsymptomsExposedindividuals weresignificantlymorelikelythanunexposedindividualsto reportwork-relatedrespiratorysymptomseyeandnoseirritation feverbodyachesandskinrashesinthe4weekspriortosurvey completionTheprevalenceofwork-relatedcoughandeye irritationamongtheexposedindividualswassignificantlyhigher ondayswhenhoteloccupancywashigh

ThewaterchemistrytestresultsatGWLmetOhiostatestandards andnoLegionellamycobacteriaorfecalcoliformbacteriawere foundinanywatersamplesAirborneendotoxinlevelsinallpool areasexceptthewaterfortexceededtheproposedACGIHRLV forendotoxinexposureandweremeasuredatlevelsthathavebeen associatedwithcoughandfever


ReCommendAtions Air Distribution System

Properventilationdesignisakeycomponenttoreducingthe levelsofairborneDBPssuchaschloraminesToaddressconcerns ofstagnantairatdecklevelGWLmodifiedtheairdistribution systembasedinpartonNIOSHrecommendationsmadeafter theinitialventilationdesignreviewWhilethechangestotheair distributionsystemmayhelpaddresstheissuesdiscussedinthis reportincludingairmovementandcontaminantremovalatthe poolsurfaceanddeckleveltheeffectofthesechangeswerenot evaluatedasapartofthisstudyThereforewerecommendthat GWLconductanevaluationoftheairdistributionsystemto determinetheeffectofthechangesmadeincluding

1 Considermeasuringdecklevelairvelocityaswell asroutinelymonitoringindirectmeasuresofsystem performancesuchastemperatureandRHatavarietyof locationsthroughoutthefacilitytohelpassessventilation effectiveness

2 Considerconductingventilationtestingsuchasair visualizationteststohelpidentifypotentialstagnantareas withinthefacility

3 ConsiderusingCFDmodelingtoevaluatetheimpact ofanyairdistributionsystemchangesonairmovement CFDisatoolthatmightbeusefultosimulatetheeffect ofanychangesonaircirculationpatternsandventilation efficiency

4 Evaluatethefacilityagainduringcoldweathertoassessthe airqualityduringtimesofhighbatherloadandlowoutdoor temperatures(whenmaximumairrecirculationoccurs)

5 Considerincreasingtheairexchangerateifimprovements inairdistributiondonotadequatelyreducechloramineand endotoxinlevels

Water System

1 Keepcombinedchlorinelevelsaslowaspossibleand continuetomaintainwaterchemistrywithinrecommended guidelines

2 Increasetheamountoffreshwaterexchangebasedon batherloadtodilutecontaminantsinthewater


ReCommendAtions (Continued) 3 Continuetoconductwaterchemistrychecksatpoolside

andcomparereadingstotheChemtrolmonitortoensure accuracyandconsistency

4 Takemultiplereadingsatvariouspoolsidelocationswithin eachwatersystematdifferenttimesofdayandatdifferent batherloadsasoftenasnecessarytofullycharacterizethe consistencyofwaterchemistryAlsomonitorwaterquality collectedfromsprayfeaturesregularlytoensuretheyare consistentwithstatestandardsandindustryguidelines

5 Considerredesigningthesprayfeaturepipingsystemtotake waterdirectlyafterthefiltrationandtreatmentcycle

6 Reducethegenerationofairbornerespirableparticlesby implementingthefollowing

a Usespraynozzlesthatproducelargerdropletswhich mayhelpreduceevaporationandaerosolizationofDBPs andbioaerosols

b Reducethecycletimeofwaterfeaturesthataerosolize water(largebucketdumpswavesetc)

7Developdisinfectionchemistrytrendsovertimeusingthe controllersrsquodataloggingfeaturesThesetrendscanhelp identifycontributingfactorsthatoccurwhensymptomsare reported

Procedure and Policy

1 Provideeducationandtrainingtoemployeesonrecognizing thesymptomsandsignsofeyeandrespiratoryirritation skinrashandasthma

2 Encourageemployeestoreportsymptomstomanagement earlyifneededreferemployeestoaphysicianpromptly

3 Keepalogofemployeesymptomsrelatedtoworkinginside theindoorpoolareaandperiodicallyreviewthelogsto lookfortrends

4 Educatepatronsontakingshowersbeforeenteringandafter leavingthepoolareaminimizingtimespentinthepool areaandencouragingchildrentouserestroomfacilities ratherthanurinatinginthepool


RefeRenCes ASHRAE[2007a]VentilationforAcceptableIndoorAirQuality ANSIASHRAEstandard621-2007AtlantaGAAmerican SocietyofHeatingRefrigeratingandAir-ConditioningEngineers Inc

ASHRAE[2007b]HeatingVentilatingandAir-Conditioning ApplicationsASHRAEHandbookAtlantaGAAmericanSociety ofHeatingRefrigeratingandAir-ConditioningEngineersInc

BarbeeSJThackaraJWRinehartWE[1983]Acuteinhalation toxicologyofnitrogentrichlorideAIHAJ44(2)145ndash146

BowenABKileJCOttoCKazerouniNAustinCBlount BCWongHNBeachMJFryAM[2007]Outbreaksofshortshyincubationocularandrespiratoryillnessfollowingexposureto indoorswimmingpoolsEnvHealthPers115(2)267ndash271

DIN19643DeutscheNormAufvereitungvonSchwimm-und BadebeckenwasserTeil12und3DINDeutschesInstitutfur NormungeVBeuth-VerlagBerlin1997

DziubanEJLiangJLCraunGFHillVYuPAPainterJMoore MRCalderonRLRoySLBeachMJ[2006]Surveillancefor waterborne-diseaseoutbreaksassociatedwithrecreationalwater mdashUnitedStates2003ndash2004MMWR55(SS12)1ndash24

FordRL[2007]Certifiedpool-spaoperatorhandbook Colorado SpringsCONationalSwimmingPoolFoundation

GagnaireFAximSBonnetPHechtGHeryM[1994] Comparisonofthesensoryirritationresponseinmicetochlorine andnitrogentrichlorideJApplToxicol14405ndash409

GunkelKJessenHJ[1988]Theproblemofureainbathingwater ZGesamteHyg34248ndash249

HeryMGerberJMHechtGSubraIPossozCAubertS DieudonneMAndreJC[1998]Exposuretochloraminesina greensaladprocessingplantAnnOccupHyg42(7)437ndash451

HeryMHechtGGerberJMGendreJCHubertGRebuffaud J[1995]Exposuretochloraminesintheatmosphereofindoor swimmingpoolsAnnOccupHyg39(4)427ndash439


RefeRenCes (Continued) HolzwarthGBalmerRGSoniL[1984]Thefateofchlorineand

chloraminesincoolingtowersWaterRes18(11)1421ndash1427

JacobsJHSpaanSvanRooyGBMeliefsteCZaatVA RooyackersJMHeederikD[2007]Exposuretotrichloramineand respiratorysymptomsinindoorswimmingpoolworkers EurRespirJ29(4)690ndash698

Kaydos-DanielsSCBeachMJShweTMagriJBixlerD[2007] Healtheffectsassociatedwithindoorswimmingpoolsasuspected toxicchloramineexposurePublicHealthEpub2007Jun25

KelsallHSimM[2001]Skinirritationinusersofbrominated poolsIntJEnvironHealthRes11(1)29ndash40

LazarovANevoKPardoAFroomP[2005]Self-reportedskin diseaseinhydrotherapistsworkinginswimmingpoolsContact Dermatitis53(6)327ndash331

LevesqueBDuchesneJFGingrasSLavoieRPrudrsquoHomme DBernardEBouletLPErnstP[2006]Thedeterminants ofprevalenceofhealthcomplaintsamongyoungcompetitive swimmersIntArchOccupEnvironHealth80(1)32ndash39

LiJBlatchleyE[2007]Volatiledisinfectionby-productformation resultingfromchlorinationoforganicndashnitrogenprecursorsin swimmingpoolsEnvironSciTechnol41(19)6732ndash6739

MassinNBohadanaABWildPHeacuteryMToamainJPHubert G[1998]Respiratorysymptomsandbronchialresponsivenessin lifeguardsexposedtonitrogentrichlorideinindoorswimming poolsOccupEnvironMed55(4)258ndash263

NeeringH[1977]Contacturticariafromchlorinatedswimming poolwaterContactDermatitis3(5)279

NeumanC[2007]TelephoneconversationonAugust142007 betweenCNeumanWaterTechnologyIncFGonzalesGreat WolfResortsandKDunnDivisionofAppliedResearchand TechnologyNationalInstituteforOccupationalSafetyandHealth CentersforDiseaseControlandPreventionUSDepartmentof HealthandHumanServices


RefeRenCes (Continued) NIOSH[2003]Hazardevaluationandtechnicalassistancereport

Bil-MarFoodsIncStormLakeIACincinnatiOHUS DepartmentofHealthandHumanServicesPublicHealthService CentersforDiseaseControlandPreventionNationalInstitutefor OccupationalSafetyandHealthNIOSHHETAReportNo2002shy0257-2916

NIOSH[2006]Hazardevaluationandtechnicalassistance reportSaraLeeFoodsStormLakeIACincinnatiOHUS DepartmentofHealthandHumanServicesPublicHealthService CentersforDiseaseControlandPreventionNationalInstitutefor OccupationalSafetyandHealthNIOSHHETAReportNo2006shy0153-3022

OhioDepartmentofHealth[2003]Disinfectionandqualityof waterInPublicSwimmingPoolsPublicSpasandSpecialUse Pools[httpwwwodhohiogovrulesfinalf3701-31aspx]Date accessedNovember202007

OhioFireCode[2006]MaximumOccupancyPermitin accordancewith13017-7-10(D)(3)Section10043

PageEHCookCKHaterMAMuellerCAGroteAAMortimer VD[2003]Visualandocularchangesassociatedwithexposureto twotertiaryaminesOccupEnvironMed6069ndash75

PardoANevoKVigiserDLazarovA[2007]Theeffectof physicalandchemicalpropertiesofswimmingpoolwaterandits closeenvironmentonthedevelopmentofcontactdermatitisin hydrotherapistsContactDermatitis50(2)122ndash126

PennyPT[1983]SwimmingpoolwheezingBrMedJ 287(6390)461ndash462

RoseCSMartynyJWNewmanLSMiltonDKKingTEBeebe JLMcCammonJBHoffmanREKreissK[1998]ldquoLifeguard lungrdquoendemicgranulatomouspneumonitisinanindoor swimmingpoolAmJPublicHealth88(12)1795ndash1800

SafranekTSemerenaSHuffmanTTheisMMagriJTorokT BeachMJBussB[2007]Ocularandrespiratoryillnessassociated withanindoorswimmingpoolmdashNebraska2006MMWR 56(36)929ndash932


RefeRenCes (Continued) SassevilleDGeoffrionGLowryN[1999]Allergiccontact

dermatitisfromchlorinatedswimmingpoolwaterContact Dermatitis41(6)347ndash348

SimonicM[2003]BathingwaterconditioningActaChimica Slovenica50587ndash591

StottmeisterEVoigtK[2006]Trichloramininderhallenbadluft ArchivdesBadewesens3158ndash162

StromBSchinnarRApterAMargolisDLautenbachE HennessySBilkerWPettittD[2003]Absenceofcross-reactivity betweensulfonamideantibioticsandsulfonamidenonantibiotics NEJM349(17)1628ndash1635

ThickettKMMcCoachJSGerberJMSadhraSBurgePS[2002] OccupationalasthmacausedbychloraminesinindoorswimmingshypoolairEurRespirJ19827ndash832

TsaiTFMaibachHI[1999]HowirritantiswaterAnoverview ContactDermatitis41(6)311ndash314

WHO[2006]Guidelinesforsaferecreationalwaterenvironments Volume2SwimmingpoolsandsimilarenvironmentsGeneva SwitzerlandWorldHealthOrganization

XieLCooperK[2006]NatatoriumstheinsidestoryASHRAE Journal48(4)16ndash27

ZajoT[2008a]NIOSHresponse31008docDocumentsentto LiliaChenMarch102008

ZajoT[2008b]07MasonVentilationChangesdocDocument senttoLiliaChenMarch202008


Appendix A tABles

Table A1 Water Chemistry ndash High Occupancy Day 1

Feature Chlorine (ppm) Sample Location No pH Free Combined

Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03

Waterfort 12 76 10 02

Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04

a A repeat measurement was taken at location 12


Appendix A tABles (Continued)

Table A2 Free and Combined Chlorine Concentrations in Water a

High Occupancy Day 1 High Occupancy Day 2 Low Occupancy Day Location

Free b Combined c Free b Combined c Free b Combined c

Activity pool 14 01-03 16 02-04 18 0-02 Leisure river 10 01-05 12 03-07 26 005-03 Childrens pool 24 03-04 10 04-05 18 01-02 Wave pool 14 0-04 20 02-06 18 0-02 Adult hot tub 20 02-04 30 02-03 36 0-02 Family hot tub 24 02-04 18 03-07 34 0-02 Waterfort 18 02-04 20 02-05 18 0-01 a All concentrations reported in ppm Data taken from the GWLrsquos Daily Air and Water Quality Logs b Measurements taken poolside at opening with DPD test kit c Measurements taken at valves near Chemtrol system with DPD test kit

Table A3 Trichloramine Air Concentrations by Location and Time ndash High Occupancy Day 1 Trichloramine Concentration (mgm3)Location 9 amndash1 pma 1 pm ndash 5 pma Meanb

Spirit Island food stand 036 ND 028 Lily pad pond 047 037 043 Leisure river by stairs 064 049 057 Top of slide tower 046 035 041 Splash pool by turn slide c 066 049 057 Adult hot tub by exhaust 055 038 047 Wave pool 061 042 052 Towel rack 039 039 039 Meanb 051 037 044 ND = Non detectable (below the LOD)a Approximate times b Used LODSQRT(2) for values below the LOD Means were calculated by taking a time-weighted average c Pump was damaged in the field so post-calibration reading was not possible To estimate post-calibration flow we incorporated the average percent error measured by the rest of the pre- and post-calibrated pumps to obtain a post-calibration flow



Table A4 Soluble Chlorine Air Concentrations by Location and Time ndash High Occupancy Day 2 Soluble Chlorine Concentration (mgm3)

Location 7 amshy9 ama

9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane

Spirit Island food stand 009 017 018 020 020 018 Lily pad pond 009 019 020 017 020 018 Leisure river by stairs Top of slide tower

019 009b

020 018

021 016

024 021c

015 021

021 017

Splash pool by turn slide 018 025 021 025 014 022 Adult hot tub by exhaust 009 020 020 020 019 019 Wave pool 009 021 023 021 023 020 Towel rack 009 016 016 015 018 015 Waterfort 009 011d 013 011 009 011 Meane 011 019 019 019 018 018 Values in bold are between the LOD and LOQ a Approximate times b Back portion of sample was lost c Pump failed Sampled for 43 minutes d Small amount of sample lost in transfer e Used LODSQRT(2) for values below the LOD Means were calculated by taking a time-weighted average

Table A5 Trichloramine Air Concentrations by Location and Time ndash High Occupancy Day 2 Trichloramine Concentration (mgm3)


9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb

Spirit Island food stand ND 040 043 042 041 038 Lily pad pond ND 078 088 083 060 072 Leisure river by stairs 009 077 093 106 074 080 Top of slide tower ND 039 045 ND 047 036 Splash pool by turn slide ND 075 090 089 070 073 Adult hot tub by exhaust ND 041 044 043 044 038 Wave pool ND 041 085 086 054 061 Towel rack ND 041 077 086 054 059 Waterfort 009 043 087 081 072 064 Mean b 007 053 072 076 057 058 Values in bold are between the LOD and LOQ ND = Non detectable (below the LOD)a Approximate times b Used LODSQRT(2) for values below the LOD Means were calculated by taking a time-weighted average



Table A6 Endotoxin Air Concentrations by Location ndash High Occupancy Day 2 Concentration Location Time (min) (EUm3)

Wave pool 500 84 Leisure river by stairs 422 67 Splash pool by turn slide 506 50 Lily pad pond 504 50 Adult hot tub by exhaust 508 46 Towel rack 509 42 Spirit Island food stand 503 25 Top of slide tower 489 25 Waterfort 507 18 Control ndash administrative office 510 2 Mean a 494 45 a Mean excludes control sample in administrative office

Table A7 Endotoxin Water Concentrations by Location ndash High Occupancy Day 2 Concentration Location (EUmL)

Surge tank ndash leisure river 77 Leisure river 76 Wave pool by mushroom fountain 61 Childrenrsquos pool 59 Surge tank ndash childrenrsquos pool 52 Control ndash womens room tap water 28 Activity pool 26 Waterfort 25 Family hot tub 19 Control ndash mens room tap water 15 Adult hot tub 054 Mean a 44 a Mean excludes control samples

Table A8 Mean Temperature and Relative Humidity

Location High Occupancy Day

1 High Occupancy Day

2 Low Occupancy Day

(F) () (F) () (F) () Spirit Island food stand Lily pad pond Leisure river by stairs Top of slide tower Splash pool by turn slide Adult hot tub by exhaust Wave pool Towel rack Waterfort

87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68

Mean 85 57 84 55 85 54 a No readings were taken at this location b Recording device failed at this location due to excessive water


Appendix B metHods

Chloramines

Asamplingpumppullsairthroughasorbenttubethattrapssolublechlorinecompoundsontosilica gelcoatedwithsulfamicacidSolublechlorinecompoundsincludemonochloraminedichloramine hypochloriteandhypochlorousacidTheairthenpassesdirectlyfromthesorbenttubethrougha37shymmpolystyrenecassetteloadedwithtwoquartzfiberfilterscoatedwithsodiumcarbonateanddiarsenic trioxidetocapturetrichloramine

TheairsampleswerecollectedusingcalibratedAircheckTM2000samplingpumps(SKCEightyFour Pennsylvania)ataflowrateof10literperminuteThesamplingpumpswerepre-andpost-calibratedwith aDryCalregDCLiteprimaryairflowmeter(BiosInternationalCorpButlerNewJersey)Sampleswere refrigeratedinthedarkandanalyzedwithin6daysofcollection

Foranalysisofthesorbenttubesthesamplesweredesorbedbyplacingtheimpregnatedsilicagelfrom thetubeintoa20mLvialTenmLofa10gLsulfamicacidsolutionwasaddedtoeachvialandthe sampleswereperiodicallyagitatedfor30minutesThesampleextractsweredecantedintoanothervial andrefrigerateduntilanalysisSampleswereanalyzedforchlorinebyinductivelycoupledplasmandashatomic emissionspectroscopyatawavelengthof134724nanometersTheLODandLOQweredeterminedfor eachsampleset

Duringanalysisofthefilterseachfilterwasremovedfromthecassetteandplacedina20mLsample vialAfter10mLofdeionizedwaterwasaddedthesampleswereperiodicallyagitatedfor30minutes Sampleswererefrigeratedandfilteredpriortoanalysisbyinductivelycoupledplasmandashatomicemission spectroscopyatawavelengthof134724nanometersTheLODandLOQweredeterminedforeach sampleset

SamplingcollectionandanalysiswasperformedaccordingtotheNIOSHdraftmethodwhichwas adaptedfromtheINRSmethod[INRS2007]

Endotoxin

Airsampleswerecollectedusinganendotoxin-free3-piece37-mmclosed-facecassettepreloadedwith045 micrompore-sizefiltersSampleswerecollectedwithAirCheck2000personalairsamplingpumpscalibrated at2litersminutepre-andpost-shiftwithaDryCalDCLiteprimaryairflowmeterWatersampleswere collectedwithsterilescrew-capcontainersfreeofdetectableendotoxinandsenttothelabforanalysis EndotoxinanalysiswasperformedbyAerotechPampK(CherryHillNJPhoenixAZ)Sampleswere analyzedforendotoxincontentwiththeKinetic-QCLreginstrumentationusingtheLALassay[Cambrex 2005]Fortheseanalyses6EUareequivalenttoonenanogramofendotoxinTheLODwas0005EU persample


Appendix B metHods (Continued)

Microbials

BulksamplesweretakenforLegionellamycobacteriaandfecalcoliformbacteriaFormicrobialsbulk watersamplesof100mLwerepouredintosterilebottlescoatedwithsodiumthiosulfatepreparedbythe contractlabSampleswerekeptcoldandinthedarkuntilanalysisAnalysisforLegionellamycobacteria andfecalcoliformbacteriawasperformedbyMicrobiologySpecialistsInc(HoustonTexas)TheColilert testprocedurewasperformedtotestfortotalcoliformsandEscherichia coli inwaterReagentwasadded to100mLofsamplewaterandincubatedfor24hoursAcolorchangeindicatedthepresenceoffecal coliformbacteriaAcolorchangethatfluorescesunderaUVlampindicatedthepresenceof Escherichia coliFormycobacteriaanalysisthesampleswereconcentratedwithacentrifugeTheconcentratewasthen placedinaBactechsystemandmonitoredweeklyfor6weeksSimultaneouslythesampleswereplatedon 7H10agarandculturedLegionellasampleswerecentrifugedplatedonbufferedcharcoalyeastextractagar andculturedfor7to10days

Sulfites and Sulfates

WatersamplesforsulfitesandsulfatesweretakeninsterilizedcontainerswithnoheadspaceAllbulk sampleswereplacedincoolersandstoredintherefrigeratoruntilpackagedoniceandshippedtothe analyticallaboratoryEachsamplewasfilteredusinga045micron25mmsyringefilterattachedtoa10 mLsyringeSulfatesandsulfiteswereanalyzedusingaDionexDX-120ionchromatographSampleswere analyzedusingtheEnvironmentalProtectionAgencyMethod3000[EPA1993]ForsulfatetheLODwas 03mgLandLOQwas083mgLforsulfitetheLODwas05mgLandLOQwas17mgL

Water Chemistry

Watertestingwasperformed withastandardcolor-matchingDPDtestkit(TaylorTechnologiesInc SparksMaryland)TwosolutionsDPD1and2wereaddedtothewatersamplewhichdevelopeda pinkish-redcolorproportionaltothefreechlorinelevelOncethefreechlorinelevelwasobtainedtotal chlorinewasthenfoundbyaddingtheDPD3solutionCombinedchlorinewascalculatedbysubtracting freechlorinefromthetotalchlorine[TaylorTechnologiesInc2007]

References

Cambrex[2005]LimulusAmebocyteLysate(LAL)Kinetic-QCLCatalogNumber50-650U WalkersvilleMD

EPA[1993]DeterminationofinorganicanionsbyionchromatographyCincinnatiOHEnvironmental MonitoringSystemsLaboratoryOfficeofResearchandDevelopmentEnvironmentalProtectionAgency Method3000Rev21



INRS[2007]NitrogentrichlorideandotherchlorinatedcompoundsParisFranceInstitutnationalde rechercheetdeseacutecuriteacuteDocument007V0101

TaylorTechnologiesInc[2007]Chemistrytopics[httpwwwtaylortechnologiescom ChemistryTopicsCMASPContentID=33]DateaccessedNovember2007


Appendix C oCCupAtionAl exposuRe limits And HeAltH effeCts

InevaluatingthehazardsposedbyworkplaceexposuresNIOSHinvestigatorsusebothmandatory (legallyenforceable)andrecommendedOELsforchemicalphysicalandbiologicalagentsasaguide formakingrecommendationsOELshavebeendevelopedbyFederalagenciesandsafetyandhealth organizationstopreventtheoccurrenceofadversehealtheffectsfromworkplaceexposuresGenerally OELssuggestlevelsofexposuretowhichmostworkersmaybeexposedupto10hoursperday40hours perweekforaworkinglifetimewithoutexperiencingadversehealtheffectsHowevernotallworkers willbeprotectedfromadversehealtheffectseveniftheirexposuresaremaintainedbelowtheselevelsA smallpercentagemayexperienceadversehealtheffectsbecauseofindividualsusceptibilityapre-existing medicalconditionandorahypersensitivity(allergy)Inadditionsomehazardoussubstancesmayactin combinationwithotherworkplaceexposuresthegeneralenvironmentorwithmedicationsorpersonal habitsoftheworkertoproducehealtheffectseveniftheoccupationalexposuresarecontrolledatthe levelsetbytheexposurelimitAlsosomesubstancescanbeabsorbedbydirectcontactwiththeskinand mucousmembranesinadditiontobeinginhaledwhichcontributestotheindividualrsquosoverallexposure

MostOELsareexpressedasaTWAexposureATWAreferstotheaverageexposureduringanormal8- to10-hourworkdaySomechemicalsubstancesandphysicalagentshaverecommendedSTELorceiling valueswherehealtheffectsarecausedbyexposuresoverashortperiodUnlessotherwisenotedthe STELisa15-minuteTWAexposurethatshouldnotbeexceededatanytimeduringaworkdayandthe ceilinglimitisanexposurethatshouldnotbeexceededatanytime

IntheUSOELshavebeenestablishedbyFederalagenciesprofessionalorganizationsstateand localgovernmentsandotherentitiesSomeOELsarelegallyenforceablelimitswhileothersare recommendationsTheUSDepartmentofLaborOSHAPELs(29CFR1910[generalindustry]29 CFR1926[constructionindustry]and29CFR1917[maritimeindustry])arelegallimitsenforceablein workplacescoveredundertheOccupationalSafetyandHealthActNIOSHRELsarerecommendations basedonacriticalreviewofthescientificandtechnicalinformationavailableonagivenhazard andtheadequacyofmethodstoidentifyandcontrolthehazardNIOSHRELscanbefoundinthe NIOSH Pocket Guide to Chemical Hazards[NIOSH2005]NIOSHalsorecommendsdifferenttypesof riskmanagementpractices(egengineeringcontrolssafeworkpracticesworkereducationtraining personalprotectiveequipmentandexposureandmedicalmonitoring)tominimizetheriskofexposure andadversehealtheffectsfromthesehazardsOtherOELsthatarecommonlyusedandcitedintheUS includetheTLVsrecommendedbyACGIHaprofessionalorganizationandtheWEELsrecommended bytheAmericanIndustrialHygieneAssociationanotherprofessionalorganizationTheTLVsand WEELsaredevelopedbycommitteemembersoftheseassociationsfromareviewofthepublishedpeershyreviewedliteratureTheyarenotconsensusstandardsACGIHTLVsareconsideredvoluntaryexposure guidelinesforusebyindustrialhygienistsandotherstrainedinthisdisciplineldquotoassistinthecontrolof healthhazardsrdquo[ACGIH2007]WEELshavebeenestablishedforsomechemicalsldquowhennootherlegal orauthoritativelimitsexistrdquo[AIHA2007]

OutsidetheUSOELshavebeenestablishedbyvariousagenciesandorganizationsandincludeboth legalandrecommendedlimitsSince2006theBerufsgenossenschaftlichesInstitutfuumlrArbeitsschutz (GermanInstituteforOccupationalSafetyandHealth)hasmaintainedadatabaseofinternationalOELs fromEuropeanUnionmemberstatesCanada(Queacutebec)JapanSwitzerlandandtheUS[httpwww


Appendix C oCCupAtionAl exposuRe limits And HeAltH effeCts (Continued)

hvbgdeebiagestislimit_valuesindexhtml]Thedatabasecontainsinternationallimitsforover1250 hazardoussubstancesandisupdatedannually

EmployersshouldunderstandthatnotallhazardouschemicalshavespecificOSHAPELsandforsome agentsthelegallyenforceableandrecommendedlimitsmaynotreflectcurrenthealth-basedinformation HoweveranemployerisstillrequiredbyOSHAtoprotectitsemployeesfromhazardsevenintheabsence ofaspecificOSHAPELOSHArequiresanemployertofurnishemployeesaplaceofemploymentfree fromrecognizedhazardsthatcauseorarelikelytocausedeathorseriousphysicalharm[Occupational SafetyandHealthActof1970(PublicLaw91ndash596sec5(a)(1))]ThusNIOSHinvestigatorsencourage employerstomakeuseofotherOELswhenmakingriskassessmentandriskmanagementdecisionsto bestprotectthehealthoftheiremployeesNIOSHinvestigatorsalsoencouragetheuseofthetraditional hierarchyofcontrolsapproachtoeliminateorminimizeidentifiedworkplacehazardsThisincludesin orderofpreferencetheuseof(1)substitutionoreliminationofthehazardousagent(2)engineering controls(eglocalexhaustventilationprocessenclosuredilutionventilation)(3)administrativecontrols (eglimitingtimeofexposureemployeetrainingworkpracticechangesmedicalsurveillance)and(4) personalprotectiveequipment(egrespiratoryprotectiongloveseyeprotectionhearingprotection) Controlbandingaqualitativeriskassessmentandriskmanagementtoolisacomplementaryapproach toprotectingworkerhealththatfocusesresourcesonexposurecontrolsbydescribinghowariskneedsto bemanaged[httpwwwcdcgovnioshtopicsctrlbanding]Thisapproachcanbeappliedinsituations whereOELshavenotbeenestablishedorcanbeusedtosupplementtheOELswhenavailable

Chloramines

Chloraminesareinorganiccompoundsformedbythereactionbetweenchlorinedisinfectantsand nitrogenouscompoundssuchasammoniaaminesororganicnitrogen-containingmaterialThespecies andconcentrationsofchloraminesareinfluencedbytheconcentrationofresidualchlorineammonia(or othernitrogensources)pHandtemperatureIngeneralthelowerthepHandthegreaterthechlorineto ammoniaratiothehigherthelikelihoodofproducingtrichloramine

Soluble Chlorine Compounds

Thetermsolublechlorinedesignatesacombinationofchlorinecompoundscollectedusingthesilica gelcontainingtubeportionofthesamplerusedThesechlorinecompoundsincludemonochloramine dichloraminehypochlorousacidandhypochloriteNoOELshavebeendevelopedforsolublechlorineor foritsspecificpossibleconstituents

Monochloramineanddichloraminearelessvolatilethantrichloraminemonochloramineisreleased intotheairabout300timessloweranddichloramineaboutthreetimesslowerthantrichloramine [Holzwarth1984]TheytendtobemoreabundantinwaterthaninairHoweverhighairconcentrations ofmonochloramineanddichloraminehavebeenfoundinenvironmentswherewaterisaerosolizedIn studiesofchloramineexposuresatpoultryfacilitiesandagreensaladprocessingfacilityeyeandupper



respiratoryirritationsymptomswereassociatedwithsolublechlorineconcentrationsInthesescenarios solublechlorinecompoundsaregeneratedfromthemixingofchlorinatedwaterwithnitrogenousproteins producedbyanimalsandplants[Heryetal1998NIOSH2003NIOSH2006]

Trichloramine

Trichloramineornitrogentrichlorideabrownish-yellowgashasapungentchlorineodorisastrong irritantandcausesexcessivetearingoftheeyes[Barbee1983]Trichloramineisthemostvolatileand prevalentchloraminecompoundintheairaroundswimmingpools[Thickettetal2002]haslow solubilityanddecomposesrapidlyinsunlightEyeandrespiratorytractirritationappeartobetheprimary effectsofexposureCurrentlynoNIOSHorOSHAOELsexistforairtrichloramineconcentration

Endotoxin

EndotoxinarelipopolysaccharideremnantsfromtheoutercellwallofGram-negativebacteriathatare releasedwhenitdies[Hagmaretal1990Olenchock1997]Gram-negativebacteriaareubiquitousinthe environmentEndotoxinhaveawiderangeofbiologicalactivitiesinvolvinginflammatoryhemodynamic andimmunologicalresponses

Inexperimentalstudieshumanvolunteersexposedviainhalationtohighlevelsofendotoxinexperience airwayandalveolarinflammationaswellaschesttightnessfeverandmalaiseandhaveanacutereduction inlungfunctionasmeasuredbyforcedexpiratoryvolumein1second[Castellan1995Milton1999] Airborneendotoxinexposuresbetween45and400EUm3havebeenassociatedwithacuteairflow obstructionmucousmembraneirritationchesttightnesscoughshortnessofbreathfeverand wheezing[Castellanetal1987Smidetal1994Miltonetal1996]Chronichealtheffectsthathave beenassociatedwithairborneendotoxinexposuresincludechronicbronchitisbronchialhyperreactivity chronicairwaysobstructionhypersensitivitypneumonitisandemphysema[Castellan1995]Apermanent decreaseinpulmonaryfunctionalongwithrespiratorysymptomshasbeenreportedinepidemiological studies[Milton1999]

Whileacausalroleforendotoxininhumanhealtheffectshasbecomemoregenerallyacceptedinrecent yearsnodose-responserelationshiphasbeenestablishedOnereasonisthatthemostcommonlyused methodofanalyzingendotoxintheLALassayisacomparativebioassay[Milton1999]Inotherwords changesintheLALtestproceduresthemselvescanerroneouslyappearaschangesinthemeasured endotoxinactivitylevelsUntilproblemswiththeLALtestareresolvedendotoxinresultscannotbe comparedtosamplescollectedatdifferenttimesoranalyzedbydifferentlaboratoriesForthesereasons ACGIHhasproposedthatRLVsratherthanthemoreusualTLVsbeusedasareferenceforendotoxin [Milton1999]



RLVsrequirethatsamplesbecollectedfromanareaconsideredtorepresentbackgroundlevelsof endotoxinandbeanalyzedatthesametimeasthesamplesfromareasofinterestTheRLVisa comparisonbetweentheenvironmentinquestionandbackgroundlevelsACGIHstatesthatifhealth effectsareconsistentwithendotoxinexposureandiftheendotoxinexposuresexceed10timesthe simultaneouslydeterminedbackgroundlevelsthentheRLVactionlevelhasbeenexceededand actionshouldbetakentoreduceexposure[Milton1999]TheproposedmaximumRLVrisesto30 timesthebackgroundlevelinanenvironmentwherenosymptomsarereported[Milton1999]When exposuresexceedtheRLVactionlevelormaximumRLVremedialactionstocontrolendotoxinlevelsare recommendedItisimportanttonotethatthenatureoftherelationshipbetweentheRLVandhealth effectshasnotbeenelucidatedatthistime

Legionella

IllnessesrelatedtoL pneumophilabacteriaaffectanestimated8000to18000peopleannuallyinthe UnitedStates[CDC2005]Atleast46speciesand70serogroupshavebeenidentifiedintheLegionella genusL pneumophilaisaubiquitousaquaticorganismthatthrivesinwarmenvironments(32degCndash45degC) andhasbeenassociatedwithover90ofthelegionellosiscasesintheUnitedStates[CDC2005] ThesourceofLegionellaisnotidentifiedinmostsporadiccasesoflegionellosis(casesoccurringinnonshyoutbreaksettings)Morecasesareusuallyidentifiedinthesummerandearlyfallbuttheycanoccurany timeofyear

EnvironmentalsamplingforLegionellacanbeusefulinafewveryspecificcircumstances(suchasin outbreakinvestigations)particularlywhenLegionellaisolatesareavailablefromoneormorecase-patients andcanthereforebetyped(specificallyidentified)andcomparedwithenvironmentalisolates[CDC 2001]OtherthaninthesespecificcircumstancesenvironmentalsamplingforLegionellaisgenerallynot recommendedbecausetheorganismsarefoundcommonlyintheenvironmentandhavebeenisolated fromnearlyeverynaturallocationwheretheyhavebeensoughtReservoirsforLegionella bacteriaare primarilyaqueous(involvingwater)andincludepotablewatersystemsair-conditioningcoolingtowers evaporativecondensersandhot-watersystems[Beninetal2002Fields2002OSHA2005aSabriaand Yu2008]

LegionellosiscanpresentintwoformsLegionnairesrsquodiseasetypicallyincludespneumoniaandcanaffect numerousorgansofthebodyillnessusuallyoccurswithin2to14daysafterexposuretothebacteria [CDC2005]TreatmentofLegionnairesrsquodiseaserequiresantibioticsPontiacfevertheotherclinicalform oflegionellosispresentsasaflu-likeillnessthatoccurswithin48to72hoursafterexposuretothebacteria [CDC2005]Pontiacfeveristreatedwithsymptom-basedtreatmentratherthanantibioticsComplete recoveryfromPontiacfevergenerallytakesplacewithinafewdaysEpidemiologicalevidenceindicatesthat theprimarymodeoftransmissionofLegionellaisviatheairborneroutefromaerosol-producingdevices [AWT2003OSHA2005b]Person-to-persontransmissionhasnotbeenreported




Nostandardorguidelinesexistforacceptablesulfiteandsulfateconcentrationsinswimmingpoolwater WatersamplesweretakenattherequestofGWLmanagement

Mycobacteria

Mycobacteriaarerod-shapedbacteriathathavecellwallswithahighlipid(fat)contentTheyarefound inagreatvarietyofnaturalandhuman-influencedaquaticenvironmentsincludinginandaround swimmingpoolshottubsandspastreateddrinkingwaterandaerosolsTheyarereadilyaerosolized fromaqueoussuspensionAerosolizationiscausedbythegenerationofairbornedropletsfrombubbles burstingatthewatersurfaceRecentlyreportshavelinkedexposuretovariousspeciesofmycobacteria inpoolsandnaturalwaterstothedevelopmentofvariousrespiratoryillnessesTheseincludebronchitis hypersensitivitypneumonitisgranulomatouspneumonitisandallergicalveolitis[Schaferetal2003]For exampleMycobacterium avium inspawaterhasbeenlinkedtohypersensitivitypneumonitisandpossibly pneumonia[Embiletal1997]Symptomswereflu-likeandincludedcoughfeverchillsmalaiseand headachesTheillnessesfollowedtheinhalationofheavilycontaminatedaerosolsgeneratedbythespa

Duetothehighlipidcontentoftheircellwallmycobacteriaareveryresistanttothedisinfectantsused inwatertreatmentincludingchlorineandozone[Engelbrechtetal1977Falkinham2003]Therefore itisessentialtomaintainrecommendeddisinfectionresidualsinhottubsspasandpoolsatalltimes toreducetherisksofacquiringswimmingpoolgranulomaorrespiratoryillnesscausedbymycobacteria Thoroughcleaningofsurfacesandmaterialsaroundpoolsandspaswheretheorganismmaypersistisalso necessary[Collinsetal1984]

References

ACGIH[2007]2007TLVsandBEIsregthresholdlimitvaluesforchemicalsubstancesandphysicalagents CincinnatiOHAmericanConferenceofGovernmentalIndustrialHygienists

AIHA[2007]2007Emergencyresponseplanningguidelines(ERPG)ampworkplaceenvironmental exposurelevels(WEEL)handbookFairfaxVAAmericanIndustrialHygieneAssociation

AWT[2003]Legionella2003AssociationofWaterTechnologies(AWT)McLeanVA[httpwwwawr orgIndustryResourcesLegionella03pdf]DateaccessedNovember202008

BarbeeSJThackaraJWRinehartWE[1983]AcuteinhalationtoxicologyofnitrogentrichlorideAmInd HygAssocJ44(2)145ndash146



BeninALBensonRFBesserRE[2002]TrendsinLegionnairesrsquodisease1980-1998decliningmortality andnewpatternsofdiagnosisClinInfectDis35(9)1039ndash1046

CastellanRM[1995]RespiratoryhealtheffectsofinhaledendotoxinsbyssinosisandbeyondIn McDuffieHDosmanJSemchukKOlenchockSedsAgriculturalHealthandSafety-Workplace EnvironmentSustainabilityBocaRatonFLCRCPresspp97ndash100

CastellanROlenchockSKinsleyKHankinsonJ[1987]Inhaledendotoxinanddecreasedspirometric valuesanexposureresponserelationforcottondustNEnglJMed317(10)605ndash610

CDC[2005]LegionellosisLegionnairesrsquodisease(LD)andPontiacfeverCentersforDiseaseControl andPreventionAtlantaGA[httpwwwcdcgovncidoddbmddiseaseinfolegionellosisghtml]Date accessedSeptember252007

CDC[2001]OutbreakofLegionnairesrsquodiseaseamongautomotiveplantworkersmdashOhio2001MMWR 50357-359[httpwwwcdcgovmmwrpreviewmmwrhtmlmm5018a1htmlDateaccessedSeptember 252007

CFRCodeofFederalRegulationsWashingtonDCUSGovernmentPrintingOfficeOfficeofthe FederalRegister

CollinsCHGrangeJMYatesMD[1984]MicrobiologicalhazardsInGuidelinesforsafe recreational-waterenvironments-volume2swimmingpoolsspasandsimilarrecreationalwater environmentsAugust2000reved[httpwwwwhointdocstorewater_sanitation_health Recreational_waterhtmVolume2recreatIIs-chap3htm]DateaccessedSeptember252007

EmbilJWarrenPYakrusMCorneSForrestDHershfieldE[1997]Pulmonaryillnessassociatedwith exposuretoMycobacterium-avium complexinhottubwaterChest111(3)534ndash536

EngelbrechtRSSeverninBFMassarikMTFarooSLeeSHHaasCNLalchandaniA[1977]New microbialindicatorsofdisinfectionefficiencyWashingtonDCUnitedStatesEnvironmentalProtection AgencyTechnologicalSeriesNoEPA6002-77-052

FalkinhamJO[2003]MycobacterialaerosolsandrespiratorydiseaseEmergInfecDis9(7)763ndash767

FieldsBSBensonRFBesserRE[2002]LegionellaandLegionnairesrsquodisease25yearsofinvestigation ClinMicrobiolRev15(3)506ndash526

HagmarLSchuumltzAHallbergTSjoumlholmA[1990]Healtheffectsofexposuretoendotoxinsandorganic dustinpoultryslaughter-houseworkersIntArchOccupEnvironHealth62159ndash164



HeryMGerberJMHechtGSubraIPossozCAubertSDieudonneMAndreJC[1998]Exposureto chloraminesinagreensaladprocessingplantAnnOccupHyg42(7)437ndash451

HolzwarthGBalmerRGSoniL[1984]ThefateofchlorineandchloraminesincoolingtowersWater Res18(11)1421ndash1427

MiltonDK[1999]Endotoxinandotherbacterialcell-wallcomponentsInMacherJed BioaerosolsassessmentandcontrolCincinnatiOHAmericanConferenceofGovernmental IndustrialHygienistspp23ndash1to23ndash14

MiltonDKWypijDKriebelDWaltersMDHammondSKEvansJS[1996]Endotoxin exposure-responseinafiberglassmanufacturingplantAmJIndMed293ndash13

NIOSH[2003]HazardevaluationandtechnicalassistancereportBil-MarFoodsIncStormLakeIA CincinnatiOHUSDepartmentofHealthandHumanServicesPublicHealthServiceCentersfor DiseaseControlandPreventionNationalInstituteforOccupationalSafetyandHealthNIOSHHETA ReportNo2002-0257-2916

NIOSH[2005]NIOSHpocketguidetochemicalhazardsCincinnatiOHUSDepartmentofHealth andHumanServicesCentersforDiseaseControlandPreventionNationalInstituteforOccupational SafetyandHealthDHHS(NIOSH)PublicationNo2005-149[httpwwwcdcgovnioshnpg]Date accessedNovember2007

NIOSH[2006]HazardevaluationandtechnicalassistancereportSaraLeeFoodsStormLakeIA CincinnatiOHUSDepartmentofHealthandHumanServicesPublicHealthServiceCentersfor DiseaseControlandPreventionNationalInstituteforOccupationalSafetyandHealthNIOSHHETA ReportNo2006-0153-3022

OlenchockS[1997]AirborneendotoxinInHurstCJKnudsenGRMcInerneyMJStetzenbach LDWalterMVedsManualofenvironmentalmicrobiologyWashingtonDCAmericanSocietyfor MicrobiologyPresspp661ndash665

OSHA[2005a]SafetyandhealthtopicsLegionnairesrsquodiseaseOccupationalSafetyampHealth Administration[httpwwwoshagovSLTClegionnairesdisease]DateaccessedNovember202007

OSHA[2005b]OSHATechnicalManualSectionIIIChapter7Legionnairesrsquodisease[httpwwwosha govdtsostaotmotm_iiiotm_iii_7html]DateaccessedNovember202007

SabriaMYuVL[2008]LegionellainfectionInFauciASKasperDLLongoDLBraunwaldEHauser SLJamesomJLLoscalzoJetsHarrisonrsquosPrinciplesofInternalMedicine17theditionpp929ndash933 McGraw-HillNewYork



SchaferMPMartinezKFMatthewsES[2003]Rapiddetectionanddeterminationoftheaerodynamic sizerangeofairbornemycobacteriaassociatedwithwhirlpoolsApplOccupEnvironHyg18(1)14ndash50

SmidTHeederickDHoubaRQuangerPH[1994]Dust-andendotoxin-relatedacutelungfunction changesandwork-relatedsymptomsinworkersintheanimalfeedindustryAmJIndMed25(6)877ndash888

ThickettKMMcCoachJSGerberJMSadhraSBurgePS[2002]Occupationalasthmacausedby chloraminesinindoorswimming-poolairEurRespirJ19827ndash832


ACknowledgements And

AvAilABility of RepoRt

TheHazardEvaluationsandTechnicalAssistanceBranch (HETAB)oftheNationalInstituteforOccupationalSafetyand Health(NIOSH)conductsfieldinvestigationsofpossiblehealth hazardsintheworkplaceTheseinvestigationsareconducted undertheauthorityofSection20(a)(6)oftheOSHAActof1970 29USC669(a)(6)whichauthorizestheSecretaryofHealthand HumanServicesfollowingawrittenrequestfromanyemployers orauthorizedrepresentativeofemployeestodeterminewhether anysubstancenormallyfoundintheplaceofemploymenthas potentiallytoxiceffectsinsuchconcentrationsasusedorfound

HETABalsoprovidesuponrequesttechnicalandconsultative assistancetofederalstateandlocalagencieslaborindustryand othergroupsorindividualstocontroloccupationalhealthhazards andtopreventrelatedtraumaanddiseaseMentionofcompany namesorproductsdoesnotconstituteendorsementbyNIOSH

ThisreportwaspreparedbyLiliaChenBichDangandCharles MuellerofHETABDivisionofSurveillanceHazardEvaluations andFieldStudiesKevinHDunnandDanielAlmaguerofthe EngineeringandPhysicalHazardsBranchDivisionofApplied ResearchandTechnology(DART)andJenniferLErnstof ChemicalExposureMonitoringBranchDARTwiththehelp ofCharlesSOttofromtheNationalCenterforEnvironmental HealthIndustrialhygienefieldassistancewasprovidedby ChandranAchutanNancyBurtonGregBurrChadDowell SrinivasDurgamLindaEwersAndreaMarkeyJessicaRamsey ManuelRodriguezandAaronSussellMedicalfieldassistance wasprovidedbyFangGongMargaretRiggsSaraLuckhaupt andAngelaWarrenAnalyticalsupportwasprovidedbyTamara WiseAerotechPampKandMicrobiologySpecialistsIncDesktop publishingwasperformedbyRobinSmithEditorialassistancewas providedbyEllenGallowayHealthcommunicationassistancewas providedbyStefanieEvansTheenvironmentalhealthevaluation wasperformedbyrepresentativesfromtheOhioDepartmentof HealthandWarrenCountyCombinedHealthDistrict

Copiesofthisreporthavebeensenttoemployeeandmanagement representativesatGreatWolfLodgetheWarrenCounty CombinedHealthDistrictandtheOSHARegionalOfficeThis reportisnotcopyrightedandmaybefreelyreproducedThereport




(Continued) maybeviewedandprintedfromthefollowinginternetaddress httpwwwcdcgovnioshhheCopiesmaybepurchasedfrom theNationalTechnicalInformationServiceat5825PortRoyal RoadSpringfieldVirginia22161


Below is a recommended citation for this report NIOSH [2008] Health Hazard Evaluation Report Investigation of employee symptoms at an indoor waterpark Mason OH Cincinnati OH US Department of Health and Human Services Public Health Service Centers for Disease Control and Prevention National Institute for Occupational Safety and Health NIOSH HETA No 2007-0163-3062

To receive NIOSH documents or information about occupational safety and health topics contact NIOSH at 1-800-CDC-INFO (1-800-232-4636) TTY 1-888-232-6348 E-mail cdcinfocdcgov

or visit the NIOSH web site at wwwcdcgovniosh

For a monthly update on news at NIOSH subscribe to NIOSH eNews by visiting wwwcdcgovniosheNews

Delivering on the Nationrsquos promise Safety and health at work for all people through research and prevention


Investigation of Employee Symptoms at an Indoor Waterpark

Employer Posting Regulation

Table of Contents13

Abbreviations13

Highlights of the NIOSH Health Hazard Evaluation13

Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13


Appendix C Occupational Exposure Limits and Health Effects13

Acknowledgements and Availability of Report13

Recommended citation for this report and additional contact information13

NIOSH Disclaimer statement This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally applicable Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved Additional HHE reports are available at httpwwwcdcgovnioshhhe

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



Summary vi

Introduction1

Assessment7

Results11

Discussion19

Conclusions30

Recommendations31

References33

Appendix A Tables37





ABBReviAtions






HigHligHts of tHe

niosH HeAltH

HAzARd evAluAtion

























summARy




















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13






Contents



Summary vi

Introduction1

Assessment7

Results11

Discussion19

Conclusions30

Recommendations31

References33

Appendix A Tables37





ABBReviAtions






HigHligHts of tHe

niosH HeAltH

HAzARd evAluAtion

























summARy




















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13






ABBReviAtions






HigHligHts of tHe

niosH HeAltH

HAzARd evAluAtion

























summARy




















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13









HigHligHts of tHe

niosH HeAltH

HAzARd evAluAtion

























summARy




















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13










summARy




















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13


















Process Description



Water Systems












Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13















Ventilation System

















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13



















Assessment Water



Ventilation


Industrial Hygiene

















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13




















Medical Interviews
















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13

















Results Water





Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13







Industrial Hygiene

Chloramines




16 45 38


20 9

30

56 170 230

6 18 97

0 62 3

94 20 0




22a

45 39


70 5

20

250 16

150

94 0

100

6 20 0

0 80 0










Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13













Endotoxin




Microbials




Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13







Medical Interviews






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13






Results (Continued)



Unexposed (N = 74)


Male ndash no () 37 (53) 24 (32)




History of






no of employees ()


Cough 48 (70) 5 (7) 1024 (433 ndash 2423) c

Wheezing 20 (29) 2 (3) 974 (236 ndash 4019) c



breath


Body aches 20 (29) 4 (5) 529 (190 ndash 1470)










Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13













Results (Continued)



1 (N = 14)


(N = 29)

Low Occupancy Day


Cough 9 (64) 16 (55) 6 (22)

Eye irritation 9 (64) 20 (69) 9 (33)

Nose irritation 4 (29) 10 (34) 4 (15)


























Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13















Water Chemistry







Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13








Ventilation





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13





























Systemic Symptoms






Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13








Skin Rash







Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13








Visual Symptoms


Limitations




day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13







day




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13




















Water System

































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13



































































Appendix A tABles



Leisure river 1 75 10 04 2 74 12 04 3 72 12 04 4 72 12 03

Wave 5 74 12 04 6 72 12 03 7 74 15 04

Activity 8 73 13 02 9 72 14 04 10 73 12 03 11 73 10 03


Repeata 74 10 03 13 72 12 02

Childrens 14 70 18 04 15 73 22 04 16 78 18 03

Adult hot tub 17 76 20 02 18 73 30 02

Family hot tub 19 71 25 04 20 72 35 04














9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13

















9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meane


019 009b

020 018

021 016

024 021c

015 021

021 017




9 amshy1 pma

1 pmshy5 pma

5 pmshy9 pma

9 pm- 11 pma

Meanb











2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13














2 Low Occupancy Day


87 85 84 88 85 85 86 83

Nonea

43 62 68 46 59 57 60 63

Nonea

84 84 83 88 83 84 86 82

NAb

46 58 60 44 57 51 54 69

NAb

86 85 84 89 85 85 86 83 83

44 50 57 41 54 57 54 63 68



Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13






Appendix B metHods

Chloramines






Endotoxin




Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13







Microbials




Water Chemistry


References

















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13



















Chloramines








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13








Trichloramine


Endotoxin







Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13








Legionella








Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13









Mycobacteria



References

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13

























































Table of Contents13

Abbreviations13


Summary13

Keywords13

Introduction13

Assessment13

Results13

Discussion13

Conclusions13

References13

Appendix A Tables13






Investigation of Employee Symptoms at an Indoor Waterpark

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Transcript of Investigation of Employee Symptoms at an Indoor Waterpark