Reopening higher education buildings in post-epidemic COVID-19 scenario: monitoring and assessment of indoor environmental quality after implementing ventilation protocols in Spain and Portugal

Indoor Air. 2022;32:e13040.   | 1 of 19 https://doi.org/10.1111/ina.13040 wileyonlinelibrary.com/journal/ina Received:28December2021 | Revised:23April2022 | Accepted:2May2022 DOI: 10.1111/ina.13040 ORIGINAL ARTICLE Reopening higher education buildings in postepidemic COVID19 scenario: monitoring and assessment of indoor environmental quality after implementing ventilation protocols in Spain and Portugal María L. de la HozTorres1 | Antonio J. Aguilar1 | Nélson Costa2 | Pedro Arezes2 | Diego P. Ruiz1 | María Dolores MartínezAires3 1DepartmentofAppliedPhysics, UniversityofGranada,Granada,Spain 2ALGORITMIResearchCenter,School ofEngineering,UniversityofMinho, Guimarães,Portugal 3DepartmentofBuildingConstruction, UniversityofGranada,Granada,Spain Correspondence AntonioJ.Aguilar,DepartmentofApplied Physics,UniversityofGranada,Av.Severo Ochoas/n,18071Granada,Spain. Email: [email protected] Funding information Thefirsttwoauthorswishtothankthe supportoftheMinisteriodeCiencia, InnovaciónyUniversidadesofSpain, underanFPUgrant.Thisresearchwas fundedbytheConsejoGeneraldela ArquitecturaTécnica(CGATE),andthe StateResearchAgency(AEI)ofSpain and European Regional Development Funds(ERDF)underprojectPID2019- 108761RB-I00.Fundingforopenaccess charge:UniversidaddeGranada/CBUA. Abstract Post-epidemicprotocolshavebeenimplementedinpublicbuildingstokeepindoor environmentssafe.However,indoorenvironmentalconditionsareaffectedbythis decision,whichalsoaffecttheoccupantsofbuildings.Thisfacthasmajorimplicationsineducationalbuildings,wherethesatisfactionandlearningperformanceof studentsmayalsobeaffected.Thisstudyinvestigatestheimpactofpost-epidemic protocols on indoor environmental conditions in higher education buildings of one PortugueseandoneSpanishuniversity.Asensormonitoringcampaigncombinedwith asimultaneousquestionnairewasconductedduringthereopeningoftheeducational buildings. Results showed that although renewal air protocols were effective and themeanCO2concentrationlevelsremainedlow(742ppmand519ppminPortugal andSpainuniversities,respectively),studentsweredissatisfiedwiththecurrentindoorenvironmentalconditions.Significantdifferenceswerealsofoundbetweenthe responses of Portuguese and Spanish students. Indeed, Spanish students showed warmerpreferences(thermalneutrality= 23.3℃)thanPortuguesestudents(thermal neutrality =20.7℃).Intermsofinvolvedindoorfactors,theobtaineddatashowed significantcorrelations(p <0.001)betweenacousticfactorsandoverallsatisfaction inthePortuguesestudents(ρ =0.540)andbetweenthermalfactorsandoverallsatisfactionintheSpanishstudents(ρ =0.522).Therefore,indoorenvironmentalconditionsshouldbeimprovedbykeepingspacessafewhileminimizingtheimpactof post-epidemicprotocolsonstudentlearningperformance. KEYWORDS buildingmanagement,builtenvironment,indoorenvironmentalquality,new-normalscenario, sensor monitoring ThisisanopenaccessarticleunderthetermsoftheCreativeCommonsAttribution-NonCommercial-NoDerivsLicense,whichpermitsuseanddistributionin anymedium,providedtheoriginalworkisproperlycited,theuseisnon-commercialandnomodificationsoradaptationsaremade. ©2022TheAuthors.Indoor AirpublishedbyJohnWiley&SonsLtd. 2 of 19 | de la HOZTORReS eT al. 1 | INTRODUCTION ThepandemicoutbreakofCOVID-19hasledtodisruptionsinhuman activities and the basic needs of the population worldwide. The rapidspreadofthesevereacuterespiratorysyndromecoronavirus- 2(SARS-CoV-2)hasresultedinthesuspensionofmanyagricultural, industrial,andcommercialactivities,causinganegativeimpacton both the global industrial and economic sectors and a deterioration in the global economy.1,2Theadoptedmeasurestolimitthespread ofSARS-CoV-2havealsoprofoundlyaffectedtheeducationsector worldwide.Morethan1.5billionlearners(89.4%ofthetotalenrolled learners)wereaffectedbytheclosureofeducationalbuildingswhen schoolsandhighereducationinstitutionswereclosedin185countriesonApril2020.3ThesouthwesternEuropeancountries,namely, SpainandPortugal,werealsoseverelyaffectedbytheCOVID-19 pandemic.ThestrictlockdownmeasuresweredecreedonMarch 12 and 13inPortugal and Spain, respectively.4,5Thesemeasures includedtheclosureofplaygrounds,schools,anduniversities,and thissituationlasteduntilearlyMayinSpainandJune20inPortugal. Educational institutions faced these circumstances and took steps to suddenly change the teaching activities and start using onlineteachingmethodologies.However,althoughthisadaptation allowedtheacademicprocesstocontinue,teachersandstudents founditdifficulttoadapttothisnewscenario.Arecentresearch studyconcludedthat50.43%oftherespondentsofSpanishuniversitiespresentedamoderate-to-severeimpactoftheoutbreak.6 In lightofthesefacts,educationalbuildingswerereopenedforsome learningactivities,duringepidemicconditions,inordertomitigate theimpactofonlineteachingonuniversitycommunities.Asaconsequence,thisprocessrequiredimplementingmeasurestoprotectthe health,safety,andwelfareofeducationalbuildingoccupantsfrom thespreadofSARS-CoV-2.Giventhatteachers,students,andstaff spendlongperiodsperdayinthesebuildings,thefirstconsideration tomaintainingahealthyenvironmentandreducingexposureriskis adilutionofpollutantswithintheindoorspace.Althoughindoorair managementwillnotstopthespreadofCOVID-19onitsown,itcan reduce the number of people infected when occupants also follow measurestocontrolandstopinfection(e.g.,theuseofmasksand practicinggoodhandhygiene).2 , 7 – 9 International organizations also published guidelines in which ventilation was considered an important factor in the safety of indoorspaces.WorldHealthOrganization(WHO)guidelinesrecommended1000ppmastheCO2 concentration limit.10TheFederation ofEuropean Heating, Ventilationand Air Containing Associations (REHVA)recommended8–10L/sperpersoninmeetingroomsand classrooms.11Inaddition,theguidelinesdrawnupbytheAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) also suggested lowering the number of building occupantsandincreasingoutdoorairventilation.Additionally,theyrecommended that ventilation systems must be run at a maximum of 2hrbeforeandafteroccupancyforpre-andpost-occupancyflushing.12Therefore,giventheimportanceofventilationineducational buildings,thecontingencyandactionplanforCOVID-19established inengineeringschoolsandfacultiesbySpanishandPortugueseuniversities also refer to ventilation among their defined measures. For example, the plan established by the University of Granada also considers the recommendation to ventilate before and after occupancyasareopeningmeasureforeducationalcenters,anditeven specified that“even ifthe weather conditions areadverse,ventilation must be carried out by means of natural ventilation through open windows and doors”.13Inaddition,the“PlanodeContingência” (ContingencyPlan)COVID-19drawupbytheUniversityofMinho alsostated“goodventilationandfrequentairrenewalmustbeensured,forexample,byopeningdoorsandwindows.Ifmechanical ventilationisused,itshouldbeinextractionmodeandneverinrecirculation mode”.14 Fortunately,theeffortsofresearchersandtherolloutofeffective vaccines have made society hopeful for a return to the “new normal.”OnSeptember1,2021,theproportionofthepopulation who had received all the doses prescribed by the vaccination protocolinPortugalandSpainwas75.5%and72.0%,respectively.15 Indeed,PortugalhadthehighestCOVID-19vaccinationrateinthe worldinSeptember.16Consequently,giventhepercentageofvaccinated people in the university community compared with that for the 2020–2021 academic year, the COVID-19 contingency plans approved by the different faculties and engineering schools were adaptedtoallowforthehighestpossibleattendanceinthe2021– 2022academicyear.Themainobjectivewastoensureasafe,secure, Practical implications - Althoughtheapplicationofpost-epidemicprotocolsin highereducationbuildingshaskeptthemeanCO2 concentration levels under control by providing an effective airrenewal,theimplementationoftheseprotocolsaffected the degree of satisfaction of indoor environmental variables that deserves to be considered. - The main dissatisfaction causes indicated by the students are outdoor noise from several sources and low thermal comfort, which are clearly related to the applicationofthepost-epidemicprotocols,andtherefore, theyshouldberevisedtobetakenintoconsideration. - Priorities for the revision of post-pandemic protocols should be focused on minimizing the interference in student learning with special care in those preferences of individuals in accordance with the climatic area that they live in. - Well-definedpatternsareidentifiedforfine-tuningthe final protocols in accordance with the specific circumstances, for example, prioritizing the improvement of acousticconditionsduringmid-seasonshouldbeconsideredinthecaseoftheAzurémCampus,andminimizing the impact of thermal conditions in the case of the FuentenuevaCampus. 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 3 of 19 de la HOZTORReS eT al. andsuitableindoorspaceforfullface-to-faceattendanceinanew- normalscenarioofpost-epidemicconditions.13,17Inthissense,exceptforthe1.5-micromanometersocialdistance,allthemeasures statedintheCOVID-19contingencyplansremainedinplaceinthe educational buildings. Inthiscontext,thestartofthe2021–2022academicyearbegan withface-to-facelearningandtheapplicationofaconditionallynormalscenario.However,sincethesemeasuresandprotocolsaffect the indoor environmental conditions in this new-normal scenario, theoccupantsatisfactionandtheindoorenvironmentalquality(IEQ) of educational building may be affected by them. Increasing the amountofoutdoorairaffectsindoorenvironmentalfactors(such as the background noise, air temperature, and relative humidity (RH)),andasaconsequence,occupants’performancemaybeaffected.1 8 – 2 1 Indeed,previousresearchstudiesconcludedthatapoorindoorenvironmentalqualityisassociatedwithadversehealtheffects andillness,leadingtostudentabsenteeism.22,23However,giventhe short time that has elapsed since society has suddenly been forced to adapt to the “new normal,” very little research has been publishedrelatedtotheimpactofthenewpost-epidemicprotocolson theindoorenvironmentalvariablesineducationalbuildings.Toaddressthisgap,theaimofthisstudywastoanalyzethesatisfaction andperceptionofuniversitystudentsinthisnewscenarioofpost- epidemicconditions.Forthispurpose,ameasurementcampaignwas conducted in educational buildings in Portugal (Azurém Campus, UniversityofMinho)andSpain(FuentenuevaCampus,Universityof Granada).Thisstudyassessedtheindoorenvironmentalconditions and the sensation and satisfaction of the students with the indoor acoustic,lighting,andthermalconditionsalongwiththeirsubjective perception of the impact of these variables on their academic performance.Thefindingswillsupportdecisionmakingfortheredesign anddevelopmentofprotocols,thusminimizingstudentdissatisfaction and ensuring that educational centers are safe. 2 | MATERIALS AND METHODS AquestionnaireandIEQmonitoringwereconductedattheAzurém Campus (University of Minho, Guimarães, Portugal) and at the FuentenuevaCampus(UniversityofGranada,Granada,Spain).Field measurements were performed during the reopening of the educationalbuildingsinthe2021/2022academicyear(duringtheperiod ofSeptember–November2021). 2.1 | Educational building case studies GuimarãesislocatedinthenorthernpartofPortugal(41°26′42″N -8°17′27″W),andtheclimatebelongstoCsbcategoryaccording totheKöppen–Geigerclimateclassification.Thisareaischaracterizedbycoldandrainywintersandhotandslightlyhumidsummers, withanaverageannualtemperaturerangefrom5to28℃. Granada islocatedinthesouthernpartofSpain(37°10′41″N-3°36′03″W), TABLE 1 Summaryoftheinvestigatedbuildings Campus Building Number of surveyed students (n) Average occupancy density (m2/person) Lighting system Type of windows Finish materials Floor Wall Ceiling Azurém (Portugal) B1 42 1.3 Suspendedandmounted fluorescent luminaire Aluminum/metal glazedwindows Wood Gypsum plaster Acoustic plasterboard B2 49 1.2 Vinyl/wood Gypsum plaster/ wood Plaster B3 81 1.2 Ceramictile Gypsum plaster/ cork Acoustic plasterboard B4 45 1.3 Vinyl Gypsum plaster/ wood Acoustic plasterboard Fuentenueva (Spain) B5 111 1.1 Mountedfluorescentluminaire Aluminumglazed windows Terrazzo Gypsum plaster Registrable suspended ceiling B6 113 1.8 Naturalstone Ceramictile Registrable suspended ceiling 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 4 of 19 | de la HOZTORReS eT al. anditsclimateisclassifiedasCsa.Granadaischaracterizedbycold winters(partlycloudy)andhotsummers.Theannualtemperature varies from 0 to 34℃,andatcertaintimesoftheyear,thethermal oscillationduringthedayislarge,oftenexceeding20℃ in 1 day. Inbothlocations,ananalysisofthecharacteristicsofteaching and learning spaces was conducted to select representative classroomsonbothcampuses.Forthispurpose,buildingmanagerswere askedtoidentifythedifferentspacesusedforundergraduatelectureclassesofeachcampus.Theseclassroomsusedfortheundergraduate students were chosen since they have the largest number ofoccupants.Amongtheseclassrooms,themeasurementcampaign wascarriedoutinthoseoneswiththedimensions,occupation,and layout representative of the spaces used for this activity in each of thebuildings.Theselectioncriteriawerethesameinbothcampuses. Asaresultofthisprocess,8classroomsdistributedin4buildingsat theAzurémCampusand7classroomsdistributedin2buildingsat theFuentenuevaCampuswereselectedintheIEQmeasurement campaign. Asummaryoftheselectedbuildings,classrooms,andnumberof surveyed students is shown in Table 1. 2.2 | IEQ sensors and experimental setup TheIEQmonitoringcampaignwasconductedduringnormallessons (1.5–2 hr), during the mid-season (from September to November 2021)inbothlocations.Differentindoorparameterswererecorded duringtheIEQmeasurement:airtemperature(℃),radianttemperature(℃),RH(%),airvelocity(m/s),CO2concentration(ppm),and light intensity (lux). Inaddition,thesoundpressurelevel (dBA) in each classroom was measured. Table 2 shows a summary of the main characteristicsoftheusedsensors.Allparametersweremeasured in1-minloggingintervals.Thesensorswereplacedinthemiddleof theclassrooms,separated>1 m from the surrounding surfaces and ataheightof0.6m. Outdoor climatological data were taken from meteorologicalstationsclosetothestudyarea.FortheareaofPortugal,the datawere obtained fromIPMA(Portuguese InstituteforSeaand Atmosphere),24andfortheareaofGranada,thedatawereobtained fromAEMET(StateMeteorologicalAgency25). Additionally,basedontheindoorairtemperaturesandradiant temperaturesvaluesobtainedfromthesensormonitoringcampaign, theoperativetemperatureswerecalculated.Thisvariableisusedin SpanishandPortugueselegislationtodefineupperandlowerlimit requirementsofthermalqualityintheindoorenvironment.Inthe caseofSpain,tworangesaredefined.Forthesummermonths(assuming 0.5 clo value and an estimated percentage of dissatisfied between 10% and 15%), the range (RS - S ) is from 23 to 25℃. For thewintermonths(assuming1clovalueandthe sameestimated percentageofunsatisfied),therange(RS - W )isfrom21to23℃.The Portugueselegislationonlyestablishesanannualrange(RP),which iswiderthanthatestablishedintheSpanishlegislation,andsetsthe operatingtemperaturelimitsfrom20to25℃.Theoperativetemperature values obtained from the field measurements were comparedwiththeindoorthermalqualityrequirementrangesofeach country. 2.3 | Data collection and analysis from questionnaires Apaper-basedcross-sectionalquestionnairewasconductedinthis study.Theconstructionofthequestionnaireinvolvedthefollowingsteps:Firstly,theprototypequestionnairewasbuiltbytheresearchgroupusingtheUNE–CEN/TR16798–2:2019Standardfor theevaluationoftheindoorenvironmentalquality.Specifically,this study followed the recommended procedures and questionnaires giveninthisStandardforthesystematicregistrationofsubjective reactionsofbuildingoccupants.Thequestionnairewasdividedinto sectionscontainingitemsrelatedtothermal,lighting,acoustic,and airqualityindoorenvironment.Theseitemsfollowedtheguidelines established in UNE-EN 10551:2019 for subjective assessment of physicalenvironment.Subsequently,inordertovalidatetheprototypequestionnaire,afocusgroupcomprisedofanexpertpanelwas conducted.Atotalof8expertsparticipatedinthisprocess,including professors and students of the related disciplines in university TABLE 2 IEQsensorcharacteristics Variable Sensor Range Accuracy Meanradianttemperature FPA805GTSAHLBORN –50to200°C 0.1℃ Airvelocity HD403TS2DeltaOHM®0.1to5m/s ±0.2 m/s +3%f.s Airtemperature FHAD46-C41AAHLBORN −20to+80°C Typical±0.2Kat5to60°C maximum ±0.4Kat5to60°C maximum ±0.7Kat−20to+80°C Relative humidity FHAD46-C41AAHLBORN 0to98%RH ±2.0%RHinrangefrom10to90%RH ±4.0%RHinrangefrom5to98%RH CO2 concentration HOBO®MX1102 0to5.000ppm ±50ppm±5%ofreading Lightintensity HOBO®MX1104 0to167,731lux ±10%typicalfordirectsunlight Soundpressurelevel Imperum-RTECNITAX® Ingeniería 35to115dBA ±1dBA 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 5 of 19 de la HOZTORReS eT al. degrees.Asaresultofthisexpertpanel,theclarityoftheformulation,andtheadequacyofthespecificvocabularyforthetextual productwereanalyzed.TheitemsrelatedtoIndoorAirQualityin theoriginalUNE–CEN/TR16798–2:2019Standardwerenotusedin our research because the experts mentioned the possible bias in the subjectiveassessmentofthisfactor,sincethestudentshadtowear afacemaskatanytimeduringthelectureclass.Finally,theresults obtainedfromthisprocesswereanalyzedandthequestionnaires were set up. Thequestionnairewasdividedintoageneralinformationsection, sections addressing the acoustic, lighting, and thermal comfort,andasectionthataddressedtheoverallevaluationoftheIEQ. Thegeneralinformationsectioncollecteddemographicdata(such astheageandgenderofthesubjects),aswellasthetypeofmask andclothingthatthesubjectswerewearingduringthesurvey.The clothesselectedfromachecklistbytheparticipantswereusedto estimate the clothing insulation value (EN ISO 7730).26 Based on thesedata,togetherwiththeoperativetemperatureandthemetabolicrate,thepredictedmeanvote(PMV)wascalculated. Regarding the IEQ questions, the thermal satisfaction vote (TSAV),lightingsatisfactionvote(LSAV),andacousticsatisfaction vote(ASAV)wereexaminedinthequestionnairebasedona7-point scale(from−3for“verydissatisfied”to3for“verysatisfied”).Inaddition,a7-pointscalewasalsousedtoexaminethethermalsensation vote(TSV,from−3for“cold”to3for“hot”),lightingsensationvote (LSV,from−3for“verybright”to3for“verydark”),andacoustic sensationvote(ASV,from−3for“verynoisy”to3for“verysilent”). Participantswereaskedtoselectthecausesofdissatisfactionusing achecklistcoveringthethermal,lighting,andacousticsituations. Moreover,toexaminetheperceivedinterference/enhancement of the indoor environmental conditions on the performance of the students, the perceived thermal impact on learning performance (PTILP),perceivedacousticimpactonlearningperformance(PAILP), andperceivedlightingimpactonlearningperformance(PLILP)were alsoassessed.Forthispurpose,thequestionnaireincludedthefollowing three direct questions: “Does the acoustic quality in your classroom space enhance or interfere with your ability to get your academicworkdone?”“Doesthelightingqualityinyourclassroom space enhance or interfere with your ability to get your academic workdone?”And“Doesthethermalqualityinyourclassroomspace enhanceorinterferewith yourabilitytogetyouracademicwork done?”A7-pointscalewasusedinthesequestions(from−3for“interferesalot”to3for“enhancesalot”).Itshouldberemarkedthat this study subjectively evaluates the perceived impact of indoor environment on the performance of students. Finally, two questions about the overall indoor environmental conditions were included in the questionnaire. The first one was abouttheoverallsatisfaction(OV1)(witha7-pointLikertscalefrom −3for“verydissatisfied”to3for“verysatisfied”).Thelastdirect question(OV2)was“Pleaseestimatehowyourproductivityisincreased or decreased by the environmental conditions in this building(i.e.,thermal,lighting,andacoustics).”Thiswasalsogradedwith alsoa7-pointscale(from−3for“decreasesalot”to3for“increases alot”).Thequestionnairewasvalidatedbyafocusexpertgroupprior to be applied to the respondents. Thefieldstudyfollowedtherecommendedproceduresstated inAnnexFofUNE-CEN/TR16798-2:2019andISO10551:2019in ordertoprovideconsistency,reliabilityofresults,andmeaningful comparisondataobtainedfrominvestigationinternationally.The questionnairesurveyswereconductedduringmiddlemorningor middleafternoon,nojustafterarrivalorafteralunchbreak.The questionnaireswerefilledoutduringthelast15minofeachlectureclasstolessenthelecturedisturbance.Thisdecisionwasintendedtomaximizetheexposureoftheuniversitystudentstothe indoor environmental condition of the classroom since the survey wasconductedattheendoftheclass(ensuringthatthestudents hadbeensittingintheclassroomforatleast1hrandminimizing the influence of metabolic rate on the thermal evaluations by the students). Afterthefieldmeasurementcampaign,thecollecteddatawere analyzedtoestimatethesatisfaction,sensationandimpactonthe learning activities of the students with the indoor environmental conditions.Theaveragesatisfactionscorewascalculatedforeach question as an arithmetic mean of the votes obtained from each campus.Moreover,fromtheresultsobtainedforthethermal,lighting,andacousticsatisfactionquestions,therateofsatisfaction(RS) anddissatisfaction(RD)wascalculatedforeachoftheindoorenvironmentalvariables(seeEquations1and2): Inaddition,therateofinterference(RI)andtherateofenhancement (RE)wereestimatedforeachvariablefromtheresultsobtainedfrom thePTILP,PLILP,andPAILPquestions(Equations3and4): (1) RateofDissatisfaction (RD) "Verydissatisfied"votes + "Dissatisfied"votes + "Slightlydissatisfied"votes Totalvotes [% ] (2) RateofSatisfaction (RS)= "Verysatisfied"votes + "Satisfied"votes + "Sightlysatisfied"votes Totalvotes [% ] (3) RateofInterference (RI)= "Interferealot"votes + "Interfere"votes + "Slightlyinterfere"votes Totalvotes [% ] (4) RateofEnhancement (RE)= "Enhancealot"votes+"Enhance"votes+"Slightlyenhance"votes Totalvotes [% ] 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 6 of 19 | de la HOZTORReS eT al. 2.4 | Statistical analysis In order to determine whether there are significant differences betweentheprobabilitydistributionsoftheresultsforbothcampuses, a statistical analysis of the data obtained in the measurement campaignswascarriedout.Forthispurpose,theprobabilitydistributionofthedatawasevaluatedusingtheKolmogorov–Smirnovtest. Nonparametrictest(theMann–WhitneyUtestortheKruskal–Wallis test)wasappliedtothenon-normallydistributedmeansofdatain order to examine the statistical significance of the possible difference between both campuses. Furthermore, the Spearman correlationtestwasdeterminedbetween:(1)thesatisfactionandthe interferenceonthelearningperformanceforeachIEQfactor;(2)the satisfactionofIEQfactorandtheoverallsatisfaction;and(3)interferenceofeachIEQfactorandtheoverallinterference. Inaddition,atendencyanalysiswascarriedoutontheobtained datasets.LinearandpolynomialfitswereusedtoassesstherelationshipbetweenthevaluesofthesubjectiveandobjectiveIEQfactors. IBMSPSSstatistic(version23.0)wasusedtoperformallthestatistical analyses. 3 | RESULTS ThegeneralinformationofrespondentsissummarizedinTable 3.A totalof440students(217fromtheAzurémCampusand223from theFuentenuevaCampus)participatedinthisfieldstudy.Sinceall the university students who participated in the surveys were sitting andlisteningtothelecturersduringthemeasurements,ametabolic rateof1.1wasmet,asstatedinISO7730.26Onbothcampuses,the majorityofrespondentswerebetween18and25yearsold(87.1% ontheAzurémCampusand91.0%ontheFuentenuevaCampus), andmostofthemwerewearingasurgicalmask(90.3%and70.4%on theAzurémCampusandFuentenuevaCampus,respectively). Regardingthetypeofclothingthestudentswerewearing,the value for the clothes was estimated using the conventional clo table definedinISO7730.26 Figure 1 shows the distribution of the clothinginsulationvaluesforthestudentsfromtheAzurémCampusand theFuentenuevaCampus. 3.1 | Indoor environmental monitoring results Theresultsobtainedfromthesensormonitoringinbothcampuses aresummarizedinTable 4.Themeanoutdoorairtemperatureobtained during the measurement survey was very similar in both locations(18.6℃inGuimarãesand19.5℃inGranada).However,the rangewaswiderinGranada(from6.8to30.2℃)thaninGuimarães (from 15.2 to 23.7℃). The difference between the mean operative temperatures during the survey in both locations was less than 1℃.Asinthecaseoftheoutdoortemperature,therangeofvalues measuredattheAzurémCampus(max.25.5℃andmin20.5℃)was narrowerthanthatofthosemeasuredattheFuentenuevaCampus (max.28.1℃andmin16.8℃). Basedonthedataobtainedfromthefieldmeasurements,the PMVwascalculated.Figure 2AshowsthemeanPMVvaluesobtained in each classroom against the indoor operative temperature. Regarding the operative temperature values obtained from theAzurémCampus,mostofthemwere in therangedefinedby thePortugueselegislationforindoorthermalquality(RP).However, half of them were below the lower limit for category 4 stated by theUNE-ENISO7730:2006Standard.Withrespecttothevalues obtainedfromtheFuentenuevaCampus,theoperativetemperature hadawiderrangethantheAzurémCampus.Onlythreeofallthe valuesareinoneofthetworanges(RS - W and RS - S )establishedinthe Spanishlegislation.However,althoughsomeofthesevaluesareoutsidetheseranges,theyareinthecategoriesdefinedbytheUNE-EN ISO7730:2006Standard. Figure 2B shows the operative temperature versus the outdoortemperature.Thelimitsoftheadaptivemethoddefinedinthe UNE-EN 16798–1:2020 Standard are included in the figure. This method is used when thermal conditions can be regulated through theopeningandclosingofwindowsanddoors,whichisapplicable duringintermediateseasons(i.e.,springandautumn).Onbothcampuses,theobtainedvaluesareincategoriesIandII,asdefinedin theStandard. RegardingtheRH,themeanindoorvaluewaslowerinGranada (38.3%) than in Guimarães (52.4%), and the indoor air velocity was similar in both locations. The CO2 concentration level value in Guimarães (ranging from 400 to 1100 ppm) was higher than thevaluesmeasuredinGranada(rangingfrom399to617ppm).If boththeaverageCO2 concentration levels are compared with the recommended limit values stated in the international guidelines, it should be noted that the average level is below the limit recommended by the REHVA (800 ppm) and the WHO (1000 ppm). Therefore, although the maximum level measured at the Azurém Campusis100ppmabovetheWHOrecommendedlimit,itispossible to state that the ventilation protocols were effective in most ofthescenariosanalyzed.Inaddition,themeanlightingvaluewas TABLE 3 Generalinformation Variable Response Portugal Spain Age n/a 9(4.1%) 11(5.0%) 1 8 – 2 5 189(87.1%) 203(91.0%) +25 19(8.8%) 9(4.0%) Sex n/a 0(0%) 1(0.4%) Male 91(41.9%) 144(64.6%) Female 126(58.1%) 78(35.0%) Typeofmask n/a 1(0.5%) 6(2.7%) FFP2 6(2.8%) 39(17.5%) Surgical 196(90.3%) 157(70.4%) Cloth 12(5.5%) 17(7.6%) Other 2(0.9%) 4(1.8%) 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 7 of 19 de la HOZTORReS eT al. 301luxinGuimarãesand434luxinGranada.Finally,theaverage backgroundnoisesoundpressurelevelLAeq value obtained at the AzurémCampuswas47.2dBA,andattheFuentenuevaCampus,it was49.7dBA. 3.2 | Subjective indoor environmental evaluation The results obtained from the analysis of the data collected in the field surveys are shown in this section. Figure 3summarizes theTSAV,LSAV,andASAVresultsobtainedfromthestudentson theenvironmentalindoorconditionsduringthefieldsurvey.First, basedontheseresults,itcanbestatedthatthegreatestdifferenceintheRSbetweenbothcampusesisinrelationtothethermal environment.TheRDwasonly10%intheAzurémCampus,while in the Fuentenueva Campus, it amounted to 36%. In addition, regarding the results of the response from the students to their lightingandacousticsatisfaction,theobtainedRSvaluesaresimilarfortheAzurémCampusandtheFuentenuevaCampus(77% and83%inthecaseoflightingRS,and74%and69%regarding acousticRS,respectively). The results regarding the response from the students for the TSV(Figure 4)showthatthemeanvalueswere0.41inGuimarães and−0.05inGranada.Itshouldbenotedthatthestudentstended tofeelneutralinbothlocations;infact,nostudentattheAzurém Campusidentifiedtheindoorthermalenvironmentaseithercoldor hot.Atthiscampus,thesumof“cool”and“slightlycool”responses was12%,andthesumof“slightlywarm”and“warm”wasequalto 41%. Incontrast, the numberofstudentswhovoted thatthe indoorspacewas“cold”and“hot”attheFuentenuevaCampuswas 2%inbothcases.Thesumoftheresponsesthatindicate“cool”and “slightlycool”ishigherthanthatobtainedfortheAzurémCampus (31%),whilethesumof“slightlywarm”and“warm”providesavalue of30%. AsstatedinASHRAE-55(2004),whenatleast80%ofthevotes from occupants are within the three central categories of the scale (i.e.,−1,0,and1),theindoorthermalenvironmentisperceivedas comfortableoracceptable.Inthisstudy,79%and70%ofvotesfrom thestudentsarewithinthethreecentralcategoriesfortheAzurém CampusandtheFuentenuevaCampus,respectively. WithrespecttotheLSVresponsesfromthestudents(Figure 5), the mean obtained values were 0.91 in Guimarães and 0.43 in Granada.Atotalof61%ofthestudentsfromtheAzurémCampus indicatedthat lighting inside classroom was “dim,”“very dark,” or “dark.”However,onlya10%ofthestudentsindicatedthattheindoorlightingenvironmentwas“light,”“bright,”or“verybright.” InthecaseoftheFuentenuevaCampus,theresultsareverydifferentthanthosefromtheAzurémCampus.Only21%indicatedthat itwas“dim,”“dark,”or“verydark.”ItisworthnotingthatiftheseresultsarecomparedwiththeLSAV,thestudentsweresatisfiedwith theseconditionseventhoughtheymainlyratedtheLSVas“neutral,” “dim,”and“dark”inbothlocations. Regarding the responses from the students about the ASV (Figure 6),theresultsshowalowerdistributionofvotesfor“neutral”thanfortheTSVandLSV.ThemeanASVvalueswere0.96in Guimarãesand0.63inGranada.Thesumoftheresponsesfromstudents who indicated that the indoor acoustic environment was “very noisy,”“noisy,”or“slightlynoisy”was16%fortheAzurémCampus. Thisvalueincreasedto26%fortheFuentenuevaCampus.Thelocationofthecampusandtheactivitiesthattakeplacearoundthem areaspectstoconsiderwhenevaluatingtheseresults.TheAzurém CampusislocatedinalargerareathantheFuentenuevaCampus, and its educational buildings are surrounded by green spaces and landscapedareas.Incontrast,theFuentenuevaCampusislocated inthecenterofthecityofGranada,atramwaycrossesthecampus, and its buildings are surrounded by main streets with a high volume of traffic. In addition to an analysis of the sensation votes and satisfaction votesonthethermal,lighting,andacousticsoftheindoorenvironmentalconditions,theRIandREofthePTILP,PLILP,andPAILPresponseswereanalyzed(Figure 7).RegardingtheAzurémCampus, the obtained results show that the environmental condition that most contributes to enhancing student performance in class is the lighting condition (RS = 77%) followed by the thermal condition (RS=71%)and,toalesserextent,theacousticcondition(RS=67%). Infact,itistheacousticconditionthatshowedthehighestRIvalue (20%). Nevertheless, the responses obtained from the survey conductedattheFuentenuevaCampusshowthattheindoorenvironmental factor that generates the greatest interference with student learningperformanceisthethermalcondition(RI=36%)followed bytheacousticcondition(RI=23%)and,toamuchlesserextent,the lightingcondition(RI=12%). Regarding the overall environmental conditions (Figure 8), it should be noted that the RS for the students at the Azurém Campus(77%)wasslightlyhigherthanthatforthestudentsatthe FuentenuevaCampus(71%).However,adifferentdistributionwas foundintheresponsesgiventheOV2question(Figure 9):75%of students at the Azurém Campus indicated that their productivity FIGURE 1 Distributionofinsulationclothingvalues 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 8 of 19 | de la HOZTORReS eT al. wasatleastslightlyincreasedbytheenvironmentalconditions(i.e., thermal,lighting,andacoustic)inthebuildingwhiletheyweredoing thequestionnaire. Incontrast,thisvalue increasedto48%inthe FuentenuevaCampus.Inaddition,thepercentageofstudentsgivinganeutralanswertothisquestionwashigherattheFuentenueva CampusthanattheAzurémCampus. 3.3 | Causes of dissatisfaction Figures 10 and 11 show the main causes of dissatisfaction at theAzurém Campus and the Fuentenuevacampus, respectively. RegardingtheAzurémCampus,studentswerefoundtobedissatisfiedwiththethermalenvironmentduetodrafts(25%),theHVAC systems not working quickly enough (14%), slow air movement (13%),andhumiditythatwastoohigh(13%).Inrelationtoindoor lighting,themaincausesofdissatisfactionwerenotenoughdaylight(29%),thespacewastoodark(26%),andnotenoughelectric lighting(16%).Indeed,71%ofthecausesofdissatisfactionwere relatedtothelackorshortageoflightingintheclassroom.This can be also observed in the data obtained during the field monitoringcampaignonthiscampus(theminimum is112lux).Interms ofacousticdissatisfaction,studentshighlightedpeopletalkingin neighboringspaces(36%)andexcessiveechoes(30%)asthemain causes.Otherexternalnoiserepresentedonly11%.Theopeningof doorsandwindowsinfluencesindooracousticconditions.Almost 50%ofthecauseswererelatedtothisfactor.Infact,noisefrom corridors and indoor/outdoor common areas was the main dissatisfactioncause.Itshouldbenotedthatone-thirdofthedissatisfactionwascausedbyclassroomarchitecturaldesign(i.e.,echoes).In addition,it shouldbenoted that the meansoundpressurelevel (backgroundnoise)measuredintheclassroomswasabovethelevel recommendedbytheWHO. AmongthecausesofthermaldissatisfactionontheFuentenueva Campus(Figure 11),wefoundthatdraftsweretheprimarycause, withavalueof26%.Thiscausewasfollowedbyhot/coldsurroundingsurfaces(16%)andhighairmovement(13%).Twoofthesethree causes are closely related to the measure of increasing the air exchangeratiointheclassroomthroughnaturalventilation(opening doorsandwindowsgeneratedraftsinsideaclassroom). Regardingtheindoorlightingenvironment,studentshaveidentifiedshadoweffectintheirworkspace(23%),toomuchbrightness (18%),andtoomuchelectriclighting(17%)asbeingthecausesofthe mostdissatisfaction.Thesecausesareoppositetothoseindicated bythestudentsattheAzurémCampus. In terms of acoustic dissatisfaction, outdoor traffic noise accounted for about one-third of the votes among the causes of acousticdissatisfaction(32%).Otherexternalnoise(25%)andpeopletalkinginneighboringspaces(22%)representedalmosthalfof the causes of dissatisfaction.Aspointed outin the previoussection,theFuentenuevaCampusislocatedinthecenterofthecityof Granada,sourbannoises(e.g.,trafficnoiseandnoisefromoutdoor activities)influencetheacousticenvironmentalconditionsinsidethe TABLE 4 Resultsobtainedfromthefieldmeasurements Country Indoor air temperature (°C) Radiant temperature (°C) Operative temperature (°C) RH (%) Air velocity (m/s) CO2 (ppm) Lighting (lux) LAeq (dBA) PaSaP S P S P S P S P S P S P S Max 25.6 28.0 25.4 28.5 25.5 28.1 69.7 50.1 0.08 0.09 1100 617 567 691 58.0 58.0 Min 20.5 16.3 20.5 17.3 20.5 16.8 28.7 28.1 0.01 0.01 400 399 112 316 38,6 43.6 Average 23.2 23.3 23.0 24.0 23.1 23.7 52.4 38.3 0.03 0.03 742 519 301 434 47.2 49.7 Median 23.4 25.3 23.2 25.8 23.3 25.6 54.9 37.6 0.02 0.01 791 517 277 377 45.7 47.8 SD 1.9 4.0 1.8 3.8 1.8 3.8 16.0 6.9 0.02 0.03 215 83 177 113 7.5 4.9 aPindicatesPortugal(AzurémCampus),andSindicatesSpain(FuentenuevaCampus). 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 9 of 19 de la HOZTORReS eT al. FIGURE 2 (A)Predictedmean votePMVversusoperativetemperature and(B)operativetemperatureversus outdoortemperature.Theblacksquares arefromthePortugaldataset,andthe bluesquaresarefromtheSpaindataset FIGURE 3 TSAV,LSAV,andASAVvaluesobtainedinPortugalandSpain.*indicatesthepercentageis<5% FIGURE 4 TSVvaluesobtainedinPortugalandSpain.*indicatesthepercentageis<5% 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License 16 of 19 | de la HOZTORReS eT al. Additionally,itshouldbenotedthatthetargetpopulationinthis study were young university students who may be not as sensitive toindoorenvironmentalconditionsasothergroups(e.g.,elderpeople41).Sincethisisourtargetpopulation,theresultsshouldnotbe extrapolated to other population groups without further analysis andverification.Therefore,furtherresearchwouldbeneededto expandthisanalysistodifferentpopulations(e.g.,childrenorolder adults)sincetheirdistinguishingfeaturesandcharacteristicsmayaffect the reported results. Inaddition,itisnoteworthythattheindoorairtemperaturewas close to the outdoor air temperature due to the continuous ventilationstrategies.Therefore,therewasnotasignificantthermalgradient since the indoor environmental condition is highly affected by the outdoor conditions. These factors influenced the natural airflowrate,whichisgeneratedbytwodrivingforces(windand temperaturedifferences),andtheymaychangequickly.Although the average air velocity obtained from the field measurements did notexceed0.1m/sinsidetheclassroom,thestudentsclosestto theopenings(windowsordoors)couldfeelit.Therefore,thePMV method may be unreliable under these circumstances and it should beusedasanorientativeorreferencevalueforthisstudy,since the thermal sensation of the occupants has been directly measured throughthethermalsensationvoteobtainedfromthequestionnaire survey. 6 | CONCLUSIONS Thisstudyevaluatedindoorenvironmentalconditionsduringthereopeningofeducationalbuildingsinthepost-epidemicCOVID-19scenariofollowing the implementation of the“new-normal” strategic measuresinSpainandPortugal.Althoughpost-epidemicprotocols haveprovidedeffectiveairrenewalandthemeanCO2 concentrationlevelsremainedbelow900ppm,theresultssuggestthattheir implementation have a significant impact on the degree of satisfactionwithindoorenvironmentalvariables.Theresultsofthisstudy indicate that students are mostly dissatisfied with the acoustic and thermal conditions. Inaddition, the students indicated thatthese variables also affected their learning performance. Inaddition,statisticallysignificantdifferenceswerefoundbetweenthepreferencesofthestudentfromFuentenuevaCampus andtheAzurémCampus:Spanishstudentsindicatedawarmerpreference (neutral temperature = 23.3℃) than Portuguese students (neutraltemperature= 20.7℃).In thissense, actions are needed to minimize the interference on students’ learning performances considering the preferences of individuals. This research shows thattheimpactfollowswell-definedpatternsthatcanbeusedfor fine-tuningthefinalprotocolsthatwouldbeappliedinthesepost- epidemiccircumstances.Forexample,basedontheresultsobtained inthisresearch,theadaptationoftheprotocolsduringmid-season shouldconsiderprioritizingtheimprovementofacousticconditions inthecaseoftheAzurémCampus,andminimizingtheimpactof thermalconditionsinthecaseoftheFuentenuevaCampus.Inany case,post-epidemicmeasuresimplementedduringconditionalnormality scenario in educational buildings should improve these indoor environmentalconditions,keepingspacessafewhileminimizingthe impactofpost-epidemicprotocolsonstudentlearningperformance. AUTHOR CONTRIBUTION MaríaL.delaHoz-TorresandAntonioJ.Aguilarinvolvedintheconceptualization, formal analysis, methodology, investigation, data curation,andwritingoftheoriginaldraft.NélsonCostaandPedro Arezesinvolvedintheconceptualizationandmethodology,contributedtoresources,andwrote,reviewed,andeditedthemanuscript. DiegoP.RuizandMªDoloresMartínez-Airesinvolvedintheconceptualizationandmethodology,contributedtoresourcesandproject administration,acquiredfunding,andwrote,reviewed,andedited the manuscript. CONFLICT OF INTERESTS Theauthorsdeclarethattheyhavenoknowncompetingfinancial interests or personal relationships that could have appeared to influencetheworkreportedinthispaper. DATA AVAILABILITY STATEMENT Dataareavailableuponrequest. PEER REVIEW Thepeerreviewhistoryforthisarticleisavailableathttps://publo ns.com/publo n/10.1111/ina.13040. ORCID María L. de la HozTorres https://orcid. org/0000-0003-1657-1572 Antonio J. Aguilar https://orcid.org/0000-0001-5045-8560 Nélson Costa https://orcid.org/0000-0002-9348-8038 Pedro Arezes https://orcid.org/0000-0001-9421-9123 Diego P. Ruiz https://orcid.org/0000-0001-5559-7383 María Dolores MartínezAires https://orcid. org/0000-0002-9292-5048 REFERENCES  1. MarinelloS,ButturiMA,GamberiniR.Howchangesinhumanactivitiesduringthelockdownimpactedairqualityparameters:Areview. 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APPENDIX A TABLE A1ResultsobtainedfromtheKruskal–WallistesttodeterminethesignificantdifferencesbetweenthedataobtainedinPortugaland Spain Satisfaction Sensation Interference TSAV LSAV ASAV TSV LSV ASV PTILP PLILP PAILP χ249.910 2.048 5.537 15.377 16.480 5.629 77.394 14.648 25.144 p-value <0.001 0.152 0.019 <0.001 <0.001 0.018 <0.001 <0.001 <0.001 TABLE A2Statisticalinformationofregressionbetweensubjectiveandobjectivevariables Input variables: TSAV– Top LSAV– lighting ASAV– LAeq PTILP– Top PLILP– Lighting PAILP– LAeq Spain R20.521 — 0.210 0.548 0.070 p-value 0.047 — 0.183 0.050 — 0.432 S.E. 0.730 — 0.506 0.478 — 0.510 F4.595 — 2.077 4.474 — 0.677 Portugal R20.110 0.274 0.192 0.263 0.293 0.094 p-value 0.422 0.449 0.278 0.466 0.420 0.461 S.E. 0.487 1.144 0.603 0.386 0.652 0.497 F0.744 0.942 1.424 0.892 1.038 0.619 TABLE A3Statisticalinformationofregressionbetweensubjectiveandoverallresponses Input variables: OV1– TSAV OV1– LSAV OV1– ASAV OV2– PTILP OV2– PLILP OV2– PAILP Spain R20.699 0.654 0.047 0.699 0.467 0.129 p-value 0.001 0.003 0.521 0.001 0.02 0.278 S.E. 0.268 0.287 0.477 0.251 0.334 0.427 F20.906 16.982 0.447 20.899 7.897 1.335 Portugal R20.584 0.364 0.677 0.570 0.526 0.894 p-value 0.027 0.113 0.012 0.030 0.042 <0.001 S.E. 0.397 0.491 0.350 0.408 0.4286 0.199 F8.412 3.434 12.557 7.960 6.654 52.590 39. BerglundB,LindvallT,SchwelaDH&WorldHealthOrganization. Occupational and Environmental Health Team. (1999). Guidelines for community noise.WorldHealthOrganization.https://apps.who. int/iris/handle/10665/66217 40. BrinkHW,LoomansMG,MobachMP,KortHS.Classrooms’indoor environmental conditions affecting the academic achievement of students and teachers in higher education: a systematic literature review. Indoor Air.2021;31(2):405-425.10.1111/ina.12745 41. Xiong J, Ma T, Lian Z, de Dear R. Perceptual and physiological responses of elderly subjects to moderate temperatures. Build Environ.2019;156:117-122.10.1016/j.buildenv.2019.04.012 How to cite this article:delaHoz-TorresML,AguilarAJ, CostaN,ArezesP,RuizDP,Martínez-AiresMD.Reopening highereducationbuildingsinpost-epidemicCOVID-19 scenario: monitoring and assessment of indoor environmentalqualityafterimplementingventilation protocolsinSpainandPortugal.Indoor Air. 2022;32:e13040. doi:10.1111/ina.13040 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License | 19 of 19 de la HOZTORReS eT al. TABLE A4Statisticalinformationofregressionbetweensubjectiveandoverallresponses Input variables: TSV– Top Spain R20.930 p-value <0.001 S.E. 0.250 F118.819 Portugal R20.353 p-value 0.121 S.E. 0.361 F3.269 TABLE A5Spearman'scorrelationanalysisbetweensubjectiveandobjectivevariables Input variables: TSAV– Top LSAV– lighting ASAV– LAeq PTILP– Top PLILP– lighting PAILP– LAeq Spain ρ0.305 −0.019 −0.044 0.307 0.026 −0.024 p-value <0.001 0.777 0.515 <0.001 0.694 0.719 Portugal ρ0.030 0.114 −0.289 −0.049 0.030 −0.129 p-value 0.659 0.094 <0.001 0.474 0.665 0.058 ρindicatesSpearman'srhocoefficient. TABLE A6Spearman'scorrelationanalysisbetweensubjectivevariablesandoverallresponses Input variables: OV1– TSAV OV1– LSAV OV1– ASAV OV2– PTILP OV2– PLILP OV2– PAILP Spain ρ0.522 0.477 0.490 0.375 0.389 0.403 p-value <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 Portugal ρ0.492 0.400 0.540 0.609 0.546 0.581 p-value <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 ρindicatesSpearman'srhocoefficient. 16000668, 2022, 5, Downloaded from https://onlinelibrary.wiley.com/doi/10.1111/ina.13040 by Universidad De Sevilla, Wiley Online Library on [27/02/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License