11

Residential Residential Indoor Air Quality: Indoor Air Quality:

An OverviewAn Overview

William J. Angell and David GrimsrudWilliam J. Angell and David GrimsrudIndoor Air Quality ProjectIndoor Air Quality Project

University of MinnesotaUniversity of Minnesota©© 20042004

22

Three PartsThree Parts

Why Indoor Air Quality? Why Why Indoor Air Quality? Why Residential IAQ?Residential IAQ?What’s New and Not New with Radon?What’s New and Not New with Radon?What is the Current Scientific What is the Current Scientific Understanding of Residential IAQ?Understanding of Residential IAQ?

What is New with Residential Ventilation What is New with Residential Ventilation Standards?Standards?

Note red slides mark major transitionsNote red slides mark major transitions

33

Why Indoor Air?Why Indoor Air?Why Residential IAQ?Why Residential IAQ?

Indoor air pollutants pose significant health risk Indoor air pollutants pose significant health risk in many indoor environmentsin many indoor environments

Pollutant concentrations higher indoors than outdoors Pollutant concentrations higher indoors than outdoors Indoor sources Indoor sources

Contaminate small indoor volumesContaminate small indoor volumesCloser proximity to peopleCloser proximity to people

Indoor pollutant up to 1000X greater chance of being inhaled Indoor pollutant up to 1000X greater chance of being inhaled than the same pollutants outdoors (Smith, 1988)than the same pollutants outdoors (Smith, 1988)

Time spent indoors greater than outdoors Time spent indoors greater than outdoors (90 to 95% vs. (90 to 95% vs. 5 to 10%)5 to 10%)

Sensitive populations spend more time in homesSensitive populations spend more time in homese.g., children 75% of time vs. adults at 60% of time (CARB, e.g., children 75% of time vs. adults at 60% of time (CARB, 2004) 2004)

44

Why Indoor Air?Why Indoor Air?Why Residential IAQ?Why Residential IAQ?

In addition,In addition,Many studies show exposures related as Many studies show exposures related as

personal > indoor > outdoorpersonal > indoor > outdoore.g.: Adgate, e.g.: Adgate, et alet al., 2004, Wallace, 1995, ., 2004, Wallace, 1995, 1996, 20011996, 2001

5

What is Not New with Radon?

Radon is a known cause of human cancerCDC, ALA, AMA, WHO and other health organizations agree that radon in U.S. homes causes thousands of lung cancer deaths each yearDocumentation of risk is 100s, if not 1000s, of times stronger than that of moldNational Academy of Sciences (1999) estimates about 15,400 to 21,800 deaths each year - but this could range from 3,000 to 32,000 per year

Risk of dying from home radon induced lung cancer for the general U.S. population is 2.3%

66

What is Not New with Radon?What is Not New with Radon?

Iowa Radon Lung Cancer StudyIowa Radon Lung Cancer Study(Fields, RW, (Fields, RW, American Journal of EpidemiologyAmerican Journal of Epidemiology, 151, 2000), 151, 2000)

Uses glass detector to measure longUses glass detector to measure long--term term residential radon exposureresidential radon exposure

Developed by D. Developed by D. SteckSteck, SJU, & R. Lively, UM, SJU, & R. Lively, UMFor exposures equivalent to 15 years spent at For exposures equivalent to 15 years spent at an average radon exposure equal to the EPA’s an average radon exposure equal to the EPA’s action level of 4 pCi/L… action level of 4 pCi/L…

…found about a 50% increased risk of lung cancer.…found about a 50% increased risk of lung cancer.

http://http://www.cheec.uiowa.edu/misc/radon.htmlwww.cheec.uiowa.edu/misc/radon.html

77

Radon: How Strong is the Radon: How Strong is the Health Evidence?Health Evidence?

1.1. Extensive epidemiologic Extensive epidemiologic studies with large numbers studies with large numbers and consistency riskand consistency risk

2.2. Extensive review by Extensive review by national/international national/international groupsgroups

National Academy of National Academy of Sciences (NAS)Sciences (NAS)World Health Organization World Health Organization (WHO)(WHO)International Commission on International Commission on Radiological Protection Radiological Protection (ICRP(ICRP--50)50)

3.3. Identified as a serious Identified as a serious public health risk by public health risk by organizations with organizations with scientific/medical expertisescientific/medical expertise

American Medical AssociationAmerican Medical AssociationAmerican Lung AssociationAmerican Lung Association

4.4. Risk model derived from Risk model derived from human data by NAShuman data by NAS

5.5. WellWell--characterized characterized exposure of the general exposure of the general population based on population based on National Residential SurveyNational Residential Survey

88

Radon: How Strong is the Radon: How Strong is the Health Evidence?Health Evidence?

6.6. Classified as a known Classified as a known human carcinogen by WHOhuman carcinogen by WHO

7.7. NAS examined the NAS examined the differences in mines/ differences in mines/ homeshomes

8.8. Extrapolation from miner to Extrapolation from miner to home risk is NOT largehome risk is NOT large

Miner risk observed at Miner risk observed at exposures as low as 40 exposures as low as 40 WLMWLMHome risk @ 4 pCi/L = 54 Home risk @ 4 pCi/L = 54 WLMWLM

9.9. Extensive peer reviewExtensive peer reviewEPA's Independent SAB EPA's Independent SAB CDCCDC

Journal of Risk AnalysisJournal of Risk Analysis

10.10. Detailed uncertainty Detailed uncertainty analysis, e.g., smoking, analysis, e.g., smoking, gender, breathing ratesgender, breathing rates

11.11. Animal studies confirm Animal studies confirm radon carcinogenicityradon carcinogenicity

12.12. International consensus International consensus on risk and U.S. action on risk and U.S. action levellevel

99

What is Not New: Reducing What is Not New: Reducing Radon ExposureRadon Exposure

Measure radon in all homes including Measure radon in all homes including apartments below the third levelapartments below the third level

If measurement is If measurement is >> 4pCi/L, install a 4pCi/L, install a mitigation system to reduce radon levelsmitigation system to reduce radon levels

Use radon resistant new construction Use radon resistant new construction techniques in new houses in higher techniques in new houses in higher probability zonesprobability zones

EPA Radon Probability MapEPA Radon Probability MapMinnesota: 45% > 4 pCi/l in living area of homes (short-term), 4th highest state

mean: 4.8 pCi/l, 5th highest state

Based upon- Geological factors- Bi-214 gamma

emissions- Soil Conservation

Service soil surveys- State Residential

Radon Surveys- Foundation type

1111

What is New with Radon?What is New with Radon?

EPA increased the risk estimate for EPA increased the risk estimate for residential 50% to 21,100 LCD/yearresidential 50% to 21,100 LCD/year (10/03)(10/03)

Risk evidence for radon is among the Risk evidence for radon is among the strongest for indoor air pollutantsstrongest for indoor air pollutants

e.g., ‘1000s X greater than mold’e.g., ‘1000s X greater than mold’

US HUD implemented a recommendation US HUD implemented a recommendation for radon testing to all FHA mortgage for radon testing to all FHA mortgage applicants applicants (02/04; Mortgage Letter 2004(02/04; Mortgage Letter 2004--04 and form HUD04 and form HUD--9256492564--CN [12/03])CN [12/03])

12

Critical Residential IAQ Scientific Review

For the Radiation and Indoor Environments National Laboratory, US Environmental Protection Agency

Survey and Critical Review of the Scientific Literature on Indoor Air Quality, Ventilation, and Building-related Health Effects in Residences Angell, WJ, Grimsrud, DT, Lee, H

2900 papers identified primarily: from North American and Europemost published 1998-2002

Asbestos, ETS, lead, pesticides, and radon excluded from review

1313

Critical Review ContentsCritical Review Contents

Health EffectsHealth EffectsCauses of BuildingCauses of Building--Related Health EffectsRelated Health EffectsPollutant Concentrations in HomesPollutant Concentrations in HomesResidential Ventilation Residential Ventilation Prevention and Mitigation StrategiesPrevention and Mitigation StrategiesRecommendationsRecommendations

1414

Health Effects: PollutantsHealth Effects: Pollutants

AsbestosAsbestosBenzeneBenzeneBiocontaminantsBiocontaminants

House Dust Mites House Dust Mites (HDM), Insects, Mold, (HDM), Insects, Mold, PetsPets

Carbon Monoxide (CO)Carbon Monoxide (CO)Environmental Tobacco Environmental Tobacco Smoke (ETS)Smoke (ETS)Formaldehyde (HCHO)Formaldehyde (HCHO)

Nitrogen Dioxide (NONitrogen Dioxide (NO22))Particles (PM)Particles (PM)PesticidesPesticidesPolycyclic Aromatic Polycyclic Aromatic Hydrocarbons (PAH)Hydrocarbons (PAH)RadonRadonSulfur Dioxide (SOSulfur Dioxide (SO22))Volatile Organic Volatile Organic Compounds (VOC)Compounds (VOC)

1515

Health Effects: DiseaseHealth Effects: DiseaseRespiratory DiseasesRespiratory Diseases(organ system most directly affected) (organ system most directly affected) –– ETS, HCHO , NOETS, HCHO , NO2 2 , SO, SO22

Allergies and Other Immune System DiseasesAllergies and Other Immune System Diseases(growing importance ~ research) (growing importance ~ research) –– HDM, Molds, NOHDM, Molds, NO22, ETS, Insects, Pets, ETS, Insects, Pets

CancerCancer (focus on lung cancer) (focus on lung cancer) –– Rn, ETS, HCHO, Molds?, +Rn, ETS, HCHO, Molds?, +

Skin and Mucous Membrane EffectsSkin and Mucous Membrane Effects–– HCHO, VOCs, ETS, NOHCHO, VOCs, ETS, NO22 ~ >Temperature & >Relative Humidity~ >Temperature & >Relative Humidity

Sensory and Central Nervous System EffectsSensory and Central Nervous System Effects(aka Sick Building Syndrome) (aka Sick Building Syndrome) –– VOCs, HCHO, ~ >Temp & >RhVOCs, HCHO, ~ >Temp & >Rh

Cardiovascular System EffectsCardiovascular System Effects –– ETS, CO, particlesETS, CO, particles

Liver and Other Organ Systematic EffectsLiver and Other Organ Systematic Effects (little evidence)(little evidence)Reproduction EffectsReproduction Effects (few non(few non--occupational studies) occupational studies)

1616

Major Building Related Major Building Related Factors: Pollutant GroupFactors: Pollutant Group

BioaerosolsBioaerosolsBacteria?Bacteria?House Dust Mites and CockroachesHouse Dust Mites and CockroachesMold and Fungal Products including ParticlesMold and Fungal Products including ParticlesPollutants Associated with DampnessPollutants Associated with Dampness

Combustion PollutantsCombustion PollutantsCarbon MonoxideCarbon MonoxideNitrogen DioxideNitrogen DioxideParticlesParticles

Volatile Organic CompoundsVolatile Organic Compounds

1717

Building Related Factors: Building Related Factors: Common Pollutant SourcesCommon Pollutant Sources

BiocontaminantsBiocontaminantsWet materials, house dust, Wet materials, house dust, HDM, cockroachesHDM, cockroaches

Carbon MonoxideCarbon MonoxideUnvented or malfunctioning Unvented or malfunctioning gas, propane, and woodgas, propane, and wood--burning appliancesburning appliancesAttached garagesAttached garages

ETSETSTobacco productsTobacco products

FormaldehydeFormaldehydeComposite wood products, Composite wood products, furnishings, paintsfurnishings, paints

Nitrogen DioxideNitrogen DioxideUnvented or malfunctioning Unvented or malfunctioning combustion appliancescombustion appliances

ParticlesParticlesCigarettes, wood stoves and Cigarettes, wood stoves and fireplaces, cooking, candles, house fireplaces, cooking, candles, house dustdust

Sulfur DioxideSulfur DioxideOutdoor sources, attached garages, Outdoor sources, attached garages, unvented combustion appliancesunvented combustion appliances

Volatile Organic CompoundsVolatile Organic CompoundsSolvents, adhesives, building Solvents, adhesives, building materials, carpets, paints, cleaning materials, carpets, paints, cleaning productsproducts

1818

IOM’s 2000 IOM’s 2000 Clearing the AirClearing the Air: : Asthma Asthma DevelopmentDevelopment EvidenceEvidence

Sufficient causalSufficient causalHouse dust miteHouse dust mite

Sufficient associationSufficient associationETS in preschool childrenETS in preschool children

Suggestive associationSuggestive associationCockroaches in preschool Cockroaches in preschool childrenchildrenRespiratory Syncytial virusRespiratory Syncytial virus

Insufficient associationInsufficient association (partial (partial list)list)

CatCatCockroachCockroachCow or horseCow or horseDogDog

Domestic birdsDomestic birdsRodentsRodentsEndotoxinsEndotoxinsETS in children & adultsETS in children & adultsFungiFungiHouseplantsHouseplantsNONO22PesticidesPesticidesPollenPollenPlasticizersPlasticizersVOCsVOCsHCHOHCHOFragrancesFragrances

1919

IOM’s 2000 IOM’s 2000 Clearing the AirClearing the Air: : Asthma Asthma ExacerbationExacerbation EvidenceEvidence

Sufficient causalSufficient causalHouse dust miteHouse dust miteCat*Cat*Cockroach*Cockroach*ETS in preschool children*ETS in preschool children*

Sufficient associationSufficient associationDog*Dog*Fungi*Fungi*Rhinovirus*Rhinovirus*NONO2 2 (~poor vent. kit. gas (~poor vent. kit. gas appliance)*appliance)*

Suggestive associationSuggestive associationInfectious agents Infectious agents (e.g. RSV)(e.g. RSV)Domestic birdsDomestic birds

ETS in children & adultsETS in children & adultsHCHOHCHOFragrancesFragrances

Insufficient associationInsufficient association(partial list)(partial list)

EndotoxinsEndotoxinsHouse PlantsHouse PlantsInsects other than Insects other than cockroachescockroachesPesticidesPesticidesPlasticizersPlasticizersVOCsVOCs

* = at this or higher evidence level for exacerbation but not cause

2020

IOM’s 2000 IOM’s 2000 Clearing the AirClearing the AirRecommendationsRecommendations

Need to completely characterize Need to completely characterize exposures when that are linked together exposures when that are linked together when studying asthmawhen studying asthma

CoCo--pollutants ~ SBS, damp buildings, and pollutants ~ SBS, damp buildings, and combustion devicescombustion devices

Need to improve understanding of physical Need to improve understanding of physical built environment as well as exposurebuilt environment as well as exposure

Must link health and building studiesMust link health and building studies

2121

Important New Asthma StudyImportant New Asthma Study(Bornehag, et al,. 2004, Environmental Health Perspectives, ehpo(Bornehag, et al,. 2004, Environmental Health Perspectives, ehponline.org, July 15)nline.org, July 15)

Nested caseNested case--control study of allergic control study of allergic reactions in children and inreactions in children and in--home home phthalate concentrationsphthalate concentrations

Associated with Associated with RhinitisRhinitis (symptoms ~ nasal irritation or inflammation) (symptoms ~ nasal irritation or inflammation)

Eczema Eczema (aka dermatitis)(aka dermatitis)

AsthmaAsthmaUsed in PVC, latex adhesives, nail polish, etc.Used in PVC, latex adhesives, nail polish, etc.

Use and exposure increased dramatically since Use and exposure increased dramatically since WW II WW II

2222

Damp Buildings and Damp Buildings and Respiratory DiseaseRespiratory Disease

Bornehag, Bornehag, et al.et al., 2001 review, 2001 reviewDampness associated Dampness associated

With respiratory symptoms (e.g., cough, wheeze, With respiratory symptoms (e.g., cough, wheeze, asthma)asthma)

1.4 to 2.2 relative risks1.4 to 2.2 relative risks

When occupants live in damp buildingsWhen occupants live in damp buildingsBut causative agents are undetermined But causative agents are undetermined

2323

IOM’s 2004 Findings: Evidence IOM’s 2004 Findings: Evidence of Health Outcomes ~ Moldof Health Outcomes ~ Mold

Sufficient causalSufficient causalnonenone

Sufficient associationSufficient associationUR tract symptomsUR tract symptomsAsthma symptoms in Asthma symptoms in asthmaticsasthmaticsHypersensitivity pneumonitis Hypersensitivity pneumonitis in susceptible person*in susceptible person*WheezeWheezeCoughCough

Suggestive associationSuggestive associationLower respiratory illness in Lower respiratory illness in healthy childrenhealthy children

Insufficient associationInsufficient association(partial list)(partial list)

Shortness of breathShortness of breathAirflow obstructions in Airflow obstructions in healthy personshealthy personsMucous membrane Mucous membrane symptomssymptomsGI tract problemsGI tract problemsAsthma developmentAsthma developmentAcute pulmonary Acute pulmonary hemorrhaging in infants hemorrhaging in infants CancerCancerLower respiratory illness in Lower respiratory illness in healthy adultshealthy adults

* = mold but not dampness

2424

IOM’s 2004 Findings: Evidence IOM’s 2004 Findings: Evidence of Health Outcomes ~ Dampnessof Health Outcomes ~ Dampness

Sufficient causalSufficient causalnonenone

Sufficient associationSufficient associationUR tract symptomsUR tract symptomsAsthma symptoms in Asthma symptoms in asthmaticsasthmaticsWheezeWheezeCoughCough

Suggestive associationSuggestive associationShortness of breathShortness of breathLower respiratory illness in Lower respiratory illness in healthy childrenhealthy childrenAsthma developmentAsthma development

Insufficient associationInsufficient association(partial list)(partial list)

Airflow obstructions in Airflow obstructions in healthy personshealthy personsMucous membrane Mucous membrane symptomssymptomsGI tract problemsGI tract problemsAcute pulmonary Acute pulmonary hemorrhaging in infants hemorrhaging in infants CancerCancerLower respiratory illness in Lower respiratory illness in healthy adultshealthy adults

* = dampness but not mold

2525

Indoor AirIndoor Air 7/04 Editorial on 7/04 Editorial on Dampness and Mold Dampness and Mold

Two significant reportsTwo significant reportsIOM, 2004 and Bornehag, IOM, 2004 and Bornehag, et al.et al., 2004 (European review), 2004 (European review)

Different approaches but similar conclusionsDifferent approaches but similar conclusionsApproachesApproaches

IOM: authors assigned to chapters based on expertise and then IOM: authors assigned to chapters based on expertise and then discussion in plenumdiscussion in plenumEurope: all authors from all disciplines discuss all studies in Europe: all authors from all disciplines discuss all studies in plenum and then reach consensus based on all studiesplenum and then reach consensus based on all studies

ConclusionsConclusionsDamp buildings and respiratory symptoms associated BUTDamp buildings and respiratory symptoms associated BUT

Causality between mold and health effects is not strongCausality between mold and health effects is not strongMold may be a cause but it is not likely to be the only causal aMold may be a cause but it is not likely to be the only causal agentgent

2626

Dampness and Respiratory Dampness and Respiratory DiseaseDisease

Dampness in buildings contributes to Dampness in buildings contributes to respiratory symptoms in both children respiratory symptoms in both children and adultsand adultsFungal agents and VOCs may contribute Fungal agents and VOCs may contribute but this is not clearbut this is not clearThereforeTherefore

Avoid or fix damp buildings and Avoid or fix damp buildings and Avoid house dust mitesAvoid house dust mites

2727

Combustion PollutantsCombustion Pollutants

PollutantsPollutantsCarbon monoxideCarbon monoxideNitrogen DioxideNitrogen DioxideParticles Particles

SourcesSourcesUnvented or malfunctioning combustion Unvented or malfunctioning combustion appliancesappliancesAttached garages Attached garages

2828

Combustion Pollutants Combustion Pollutants SourcesSources

Unvented or malfunctioning combustion Unvented or malfunctioning combustion appliancesappliances

South Minneapolis homes under worst caseSouth Minneapolis homes under worst case20% of gas water heaters backdrafted20% of gas water heaters backdrafted10% of gas furnaces backdrafted (Bohac, 2002)10% of gas furnaces backdrafted (Bohac, 2002)

Attached garagesAttached garages80% of Minnegasco multi80% of Minnegasco multi--alarm homes resulted from alarm homes resulted from attached garage CO (Wilber and Klossner, 1997)attached garage CO (Wilber and Klossner, 1997)

Unvented gas fireplacesUnvented gas fireplacesProduced 47 to 78 ppm of CO for 2 to 9 hours Produced 47 to 78 ppm of CO for 2 to 9 hours (Dutton, (Dutton, et al., et al., 2001) 2001)

2929

Carbon Monoxide (CO)Carbon Monoxide (CO)

Demands special attention because of its Demands special attention because of its acute effectsacute effects

Death rate appears to be declining Death rate appears to be declining LongLong--term, lowterm, low--level exposures deserve level exposures deserve additional attentionadditional attention

“Occult” poisoning“Occult” poisoningHidden rather supernaturalHidden rather supernaturalOccurs when CO is less than UL alarm threshold Occurs when CO is less than UL alarm threshold

Several issues merit attentionSeveral issues merit attention

3030

CO Issues: Top Five Worldwide CO Issues: Top Five Worldwide Public Health ProblemPublic Health Problem

Exposure to CO and other combustion Exposure to CO and other combustion pollutants from unvented cooking and pollutants from unvented cooking and other devices in developing counties is a other devices in developing counties is a major worldwide public health problemmajor worldwide public health problem

Perhaps fifth afterPerhaps fifth afterMalnutritionMalnutritionTobaccoTobaccoHIVHIVPoor waterPoor water

Smith, et al., 2002Smith, et al., 2002

3131

CO Issues: Low Level CO Issues: Low Level Chronic Indoor ExposuresChronic Indoor Exposures

Largely a neglected area of study yet, Largely a neglected area of study yet, several indicators of importanceseveral indicators of importance

15% of myocardial ischemia attributed to 15% of myocardial ischemia attributed to COHb above 1% (nonsmokers ~.5 to 1% COHb above 1% (nonsmokers ~.5 to 1% COHb; Lambert, 1994)COHb; Lambert, 1994)Significant impairment of higher cognitive Significant impairment of higher cognitive function at 1 to 7% COHb (Amitai function at 1 to 7% COHb (Amitai et al.et al. 1998)1998)

e.g., memory, learning ability, attention span and e.g., memory, learning ability, attention span and concentrationconcentration

3232

CO Issues Meriting AttentionCO Issues Meriting Attention

Better isolation of attached garagesBetter isolation of attached garagesCombustion appliancesCombustion appliances

Better maintenance of existing appliancesBetter maintenance of existing appliancesGuidelines and standards needed for local venting of Guidelines and standards needed for local venting of combustion products to the outsidecombustion products to the outsideDirect vented combustion equipment should be used Direct vented combustion equipment should be used whenever possiblewhenever possible

Better CO alarmsBetter CO alarmsProtection against acute CO events would be enhanced Protection against acute CO events would be enhanced by better CO alarmsby better CO alarms

3333

Important New NOImportant New NO22 Study Study

Cauhan Cauhan et al.et al., 2003, 2003Studied group of 114 asthmatic UK children Studied group of 114 asthmatic UK children and track personal NOand track personal NO22 exposure, respiratory exposure, respiratory symptoms, peak expiration flowsymptoms, peak expiration flow

High exposure to NOHigh exposure to NO22 in the week before the start in the week before the start of a respiratory viral infection is associated with of a respiratory viral infection is associated with increase severity of a resulting asthma increase severity of a resulting asthma exacerbationexacerbation

Median exposure for children in homes with Median exposure for children in homes with Gas cooking: 12 Gas cooking: 12 µµg/mg/m33

Electric cooking: 8.5 Electric cooking: 8.5 µµg/mg/m33

Little personal NOLittle personal NO22 fluctuation from to outdoor NOfluctuation from to outdoor NO22

3434

ParticlesParticles

Outdoor fine PM longOutdoor fine PM long--term exposureterm exposureEach 10 Each 10 µµg/m3 increase =g/m3 increase =

4% increase all mortality4% increase all mortality6% increase in cardiopulmonary mortality6% increase in cardiopulmonary mortality10% increase in lung10% increase in lung--cancer mortality (Pope cancer mortality (Pope et al.et al., , 2002)2002)

How do results relate to residential health?How do results relate to residential health?e.g., most exposure indoors, important sources in e.g., most exposure indoors, important sources in homeshomes

3535

ParticlesParticlesClassic review by Wallace, 1996Classic review by Wallace, 1996

Summarizes Harvard Six Cities studies, NYSERDA Summarizes Harvard Six Cities studies, NYSERDA field study, and EPA Pfield study, and EPA P--TEAM studyTEAM study

ExposureExposureOutdoor < indoor < personalOutdoor < indoor < personal

Indoors, people are nearer PM sourcesIndoors, people are nearer PM sourcesMajor sources of indoor PMMajor sources of indoor PM

Cigarette smokingCigarette smokingCookingCooking

Abt Abt et al.,et al., 2000: PM 2000: PM indoorsindoors sources and sinkssources and sinksCooking (boiling, baking, toasting, barbecuing, Cooking (boiling, baking, toasting, barbecuing, sautéing, frying)sautéing, frying)Cleaning (vacuum, dusting, sweeping)Cleaning (vacuum, dusting, sweeping)Foot traffic Foot traffic

`

3636

VOC ExposureVOC Exposure

Health effects in children Health effects in children > Pulmonary infection rate ~> Pulmonary infection rate ~

Indoor painting during pregnancyIndoor painting during pregnancyAdhesiveAdhesive--applied carpet during pregnancy applied carpet during pregnancy (Diez et al., 2000)(Diez et al., 2000)

Bronchial obstruction ~Bronchial obstruction ~PVC flooring or textile wall material PVC flooring or textile wall material (Jaakola et al., 2002)(Jaakola et al., 2002)

OR higher ~ air change rate < 0.5 ACH ~ higher concentrations ofOR higher ~ air change rate < 0.5 ACH ~ higher concentrations of HCHO, HCHO, PVC, etc. PVC, etc.

Asthma symptoms in adultsAsthma symptoms in adultsCaused by indoor VOCs and HCHO Caused by indoor VOCs and HCHO (Norback et al., 1995)(Norback et al., 1995)

..

3737

VOC ExposuresVOC Exposures

Understanding of VOCs in buildings very Understanding of VOCs in buildings very important (cf., Adgate, 2004)important (cf., Adgate, 2004)Important to characterize, whenever Important to characterize, whenever possible:possible:

Personal exposure ~Personal exposure ~Indoor exposure ~Indoor exposure ~Outdoor exposureOutdoor exposure

3838

CoCo--Pollutants: Pollutants: Ozone Ozone -- Initiated Indoor ChemistryInitiated Indoor Chemistry

(Weschler, CJ [2004] Atmospheric Environment 38, 5715 (Weschler, CJ [2004] Atmospheric Environment 38, 5715 -- 5716)5716)

Outdoor OOutdoor O33 associated with health effectsassociated with health effectse.g., respiratory symptoms and asthma med usee.g., respiratory symptoms and asthma med use

Indoor OIndoor O33 interacts withinteracts withe.g., 5 to 10% of airborne organic compounds containing e.g., 5 to 10% of airborne organic compounds containing unsaturated carbon unsaturated carbon -- carbon bondscarbon bondse.g., surfacee.g., surface--bound organics => HCHO & aldehydesbound organics => HCHO & aldehydes

Greater health concerns than OGreater health concerns than O33 by itselfby itselfExacerbate asthmaExacerbate asthma

(Common indoor sources: air cleaning devices and laser printers)(Common indoor sources: air cleaning devices and laser printers)

May be easier to remove indoor OMay be easier to remove indoor O33 than from than from outdoor airoutdoor air

3939

Pollutant Concentrations Pollutant Concentrations in Residencesin Residences

Combustion pollutantsCombustion pollutantsCarbon monoxide (CO)Carbon monoxide (CO)Nitrogen dioxide (NONitrogen dioxide (NO22))Fine particles (PMFine particles (PM2.52.5))

Volatile Organic Compounds (VOCs)Volatile Organic Compounds (VOCs)Formaldehyde Formaldehyde -- buildingbuilding--related aldehyderelated aldehydeBenzene Benzene –– occupantoccupant--related VOCrelated VOCTVOC (Total VOCs)TVOC (Total VOCs)

4040

Pollutant Concentrations: Pollutant Concentrations: COCO

CO Concentrations

0.1

1.0

10.0

100.0

1000.0

A B C D E F G H I J K L M N O P

Study Label

CO

Con

cent

ratio

n in

ppm

90 %le10 %leMedian

4141

Typical Pollutant Concentrations: Typical Pollutant Concentrations: COCO

WHO guideline for 15 min. exposure to CO WHO guideline for 15 min. exposure to CO (90 ppm) is shown in the upper double(90 ppm) is shown in the upper double--dashed line; the 8 hour guideline dashed line; the 8 hour guideline concentration (10 ppm) is shown in the concentration (10 ppm) is shown in the lower dashed linelower dashed line

A. Akland et al.(1985) 1A. Akland et al.(1985) 1--hr personal hr personal exposures in Washington, DC*exposures in Washington, DC*

B. Akland et al (1985) 8B. Akland et al (1985) 8--hr personal hr personal exposures in Washington, DC*exposures in Washington, DC*

C. Akland et al (1985) 1C. Akland et al (1985) 1--hr personal hr personal exposures in Denver*exposures in Denver*

D. Akland et al (1985) 8D. Akland et al (1985) 8--hr personal hr personal exposures in Denver*exposures in Denver*

E. Wallace (2000) in townhouse in E. Wallace (2000) in townhouse in Washington, DCWashington, DC

F. Grimsrud et al. (1996) 3 of 10 new F. Grimsrud et al. (1996) 3 of 10 new furnaces backdrafting, MNfurnaces backdrafting, MN

* = during normal activities * = during normal activities

G. Wilber and Klossner (1997) 37 of 50 CO G. Wilber and Klossner (1997) 37 of 50 CO alarm homes with attached garages and alarm homes with attached garages and 8 of 50 with ovens producing CO, MN8 of 50 with ovens producing CO, MN

H. Nagda et al. (2002) average values for H. Nagda et al. (2002) average values for appliance rooms in MD and NEappliance rooms in MD and NE

I. Nagda et al. (2002) maximum values for I. Nagda et al. (2002) maximum values for appliance rooms in MD and NEappliance rooms in MD and NE

J. Nagda et al. (2002) average values for living J. Nagda et al. (2002) average values for living rooms in MD and NErooms in MD and NE

K. K. Nagda et al. (2002) maximum values for Nagda et al. (2002) maximum values for living rooms in MD and NEliving rooms in MD and NE

L. Grimsrud and Hadlich (1999) average values L. Grimsrud and Hadlich (1999) average values for appliance (mechanical) rooms for appliance (mechanical) rooms

M. Grimsrud and Hadlich (1999) maximum M. Grimsrud and Hadlich (1999) maximum values for appliance (mechanical) roomsvalues for appliance (mechanical) rooms

N. Grimsrud and Hadlich (1999) average values N. Grimsrud and Hadlich (1999) average values for living rooms in MNfor living rooms in MN

O. Grimsrud and Hadlich (1999) maximum O. Grimsrud and Hadlich (1999) maximum values for living rooms in MNvalues for living rooms in MN

P. Dutton et al. (2001) unvented natural gas P. Dutton et al. (2001) unvented natural gas fireplaces, COfireplaces, CO

4242

Pollutant Concentrations:Pollutant Concentrations:NONO22

NO2 Concentrations

1

10

100

1000

A B C D E F G H I J

Study Label

NO

2 C

once

ntra

tions

(ug/

m3)

90 %le10 %lemedian

4343

Typical Pollutant Concentrations:Typical Pollutant Concentrations:NONO22

The WHO guideline for 1 hr. The WHO guideline for 1 hr. exposure to NOexposure to NO22 (200 ug/m(200 ug/m33) is ) is shown in the upper doubleshown in the upper double--dashed line; the 1 yr guideline dashed line; the 1 yr guideline concentration (40 concentration (40 µµg/m3) is g/m3) is shown in the lower dashed lineshown in the lower dashed line

A. A. Speizer et al. (1980) gas ranges Speizer et al. (1980) gas ranges in 6 cities, USin 6 cities, US

B. B. Speizer et al. (1980) electric Speizer et al. (1980) electric ranges in 6 cities, USranges in 6 cities, US

C. Pilotto et al. (1997) unvented C. Pilotto et al. (1997) unvented gas heaters, Australiagas heaters, Australia

D. D. Ciuk et al. (2001) gas appliances, Ciuk et al. (2001) gas appliances, AustraliaAustralia

E. E. Ciuk et al. (2001) electric Ciuk et al. (2001) electric appliances, Australiaappliances, Australia

F. F. Garrett, Hooper et al. (1998) gas Garrett, Hooper et al. (1998) gas ranges, Australiaranges, Australia

G. Monn et al. (1998) SwitzerlandG. Monn et al. (1998) SwitzerlandH. Shima and Adachi (2000) H. Shima and Adachi (2000)

vented gas heaters, Japanvented gas heaters, JapanI. I. Shima and Adachi (2000) Shima and Adachi (2000)

unvented gas heaters, Japanunvented gas heaters, JapanJ Dutton et al. (2001) unvented J Dutton et al. (2001) unvented

gas fireplaces, COgas fireplaces, CO

4444

Pollutant Concentrations:Pollutant Concentrations:PMPM2.52.5

PM 2.5 Concentrations

1.0

10.0

100.0

A B C D E F G H I J K L

Study label

PM 2

.5 C

once

ntra

tion

(ug/

m3)

90th'le10th 'leMedian

90

4545

Typical Pollutant Concentrations:Typical Pollutant Concentrations:PMPM2.52.5

There is no WHO guideline for fine There is no WHO guideline for fine particlesparticles

A.A. Wallace (1996), NY, 224 Wallace (1996), NY, 224 houseshouses

B. B. Wallace (1996), NY, 209 Wallace (1996), NY, 209 houseshouses

C. C. Wallace (1996), CA daytime, Wallace (1996), CA daytime, probability samplingprobability sampling

D. D. Wallace (1996), CA night, Wallace (1996), CA night, probability samplingprobability sampling

E.E. Abt et al. (2000), MA intense Abt et al. (2000), MA intense sampling in four homessampling in four homes

F. F. RojasRojas--Bracho et al. (2000), MA, Bracho et al. (2000), MA, indoor exposuresindoor exposures

G. RojasG. Rojas--Bracho et al. (2000), MA, Bracho et al. (2000), MA, personal exposurespersonal exposures

H. Long et al. (2001), MA, nine H. Long et al. (2001), MA, nine homeshomes

I. I. Leaderer et al. (1999), VA, airLeaderer et al. (1999), VA, air--conditioned homes, summerconditioned homes, summer

J. Leaderer et al. (1999), VA, non J. Leaderer et al. (1999), VA, non airair--conditioned homes, summerconditioned homes, summer

K. Leaderer et al. (1999), CT, VA, K. Leaderer et al. (1999), CT, VA, homes with kerosene heaters, homes with kerosene heaters, winterwinter

L. L. Leaderer et al. (1999), CT, VA, Leaderer et al. (1999), CT, VA, homes without kerosene homes without kerosene heaters, winterheaters, winter

4646

Typical Pollutant Concentrations:Typical Pollutant Concentrations:HCHOHCHO

Formaldehye Concentrations

1

10

100

1000

A B C D E F

Study Label

HC

HO

Con

cent

ratio

ns (u

g/m

3)

90th 'le10th 'leMedian

4747

Typical Pollutant Concentrations:Typical Pollutant Concentrations:HCHOHCHO

Sources: manufactured wood products, carpet, etc.Sources: manufactured wood products, carpet, etc.WHO guideline value for formaldehyde, a suspected human carcinogWHO guideline value for formaldehyde, a suspected human carcinogen, is en, is

100 100 µµg/m3 and is shown in the figure as a horizontal dashed line g/m3 and is shown in the figure as a horizontal dashed line A. Garrett, Abramson, et al. (1998) Repeated measurements in 80A. Garrett, Abramson, et al. (1998) Repeated measurements in 80 houses houses

in Australia.in Australia.B. Hodgson et al. (2000) Measurements in 4 new manufactured andB. Hodgson et al. (2000) Measurements in 4 new manufactured and 7 7

new sitenew site--built houses that were unoccupied in the US (Florida).built houses that were unoccupied in the US (Florida).C. NorbC. Norbääck et al (1995) Measurements in 47 Swedish houses where ck et al (1995) Measurements in 47 Swedish houses where

occupants had symptoms of nocturnal breathlessness.occupants had symptoms of nocturnal breathlessness.D. NorbD. Norbääck et al (1995) Measurements in 41 Swedish houses where ck et al (1995) Measurements in 41 Swedish houses where

occupants did not have symptoms of nocturnal breathlessness.occupants did not have symptoms of nocturnal breathlessness.E. Bornehag and Stridh (2000) Measurements in 178 randomly seleE. Bornehag and Stridh (2000) Measurements in 178 randomly selected cted

Swedish dwellings.Swedish dwellings.F. F. Brown (2002) Measurements in a new dwelling in Australia showingBrown (2002) Measurements in a new dwelling in Australia showing the the

decay of concentration over time.decay of concentration over time.

4848

Typical Pollutant Concentrations: Typical Pollutant Concentrations: BenzeneBenzene

Benzene Concentrations

0

1

10

100

A B C D E F

Study Label

C6H

6 C

once

ntra

tions

(ug/

m3 )

90th 'le10th 'leMedian

4949

Typical Pollutant Concentrations: Typical Pollutant Concentrations: BenzeneBenzene

Sources: auto exhaust, tobacco smoke, unvented clothes dryersSources: auto exhaust, tobacco smoke, unvented clothes dryersThere is no WHO guideline value for benzene, a human carcinogenThere is no WHO guideline value for benzene, a human carcinogenA. Brown (2002) Measurements from 27 houses in AustraliaA. Brown (2002) Measurements from 27 houses in AustraliaB. Kostiainen (1995) Measurements in 50 nonB. Kostiainen (1995) Measurements in 50 non--complaint houses in complaint houses in

FinlandFinlandC. Kostiainen (1995) Measurements in 7 complaint houses in C. Kostiainen (1995) Measurements in 7 complaint houses in

FinlandFinlandD. Adgate et al. (2002) Measurements in 284 houses with childrenD. Adgate et al. (2002) Measurements in 284 houses with children

in the US (MN)in the US (MN)E. Van Winkle and Scheff (2001) Measurements in 10 houses in E. Van Winkle and Scheff (2001) Measurements in 10 houses in

the US (IL)the US (IL)F. Brown et al. (1994) Summary of 2000+ measurements from US, F. Brown et al. (1994) Summary of 2000+ measurements from US,

Netherlands, and Denmark. Netherlands, and Denmark.

5050

Typical Pollutant Concentrations: Typical Pollutant Concentrations: TVOCTVOC

TVOC Concentrations

1

10

100

1000

10000

100000

A B C D E F G H I J K L

Study Label

TVO

C C

once

ntra

tions

(ug/

m3)

90th 'le

10th 'le

Median

5151

Typical Pollutant Concentrations: Typical Pollutant Concentrations: TVOCTVOC

There is no WHO guideline for TVOCThere is no WHO guideline for TVOCA. A. Brown et al. (1994). Brown et al. (1994).

Measurements from established Measurements from established dwellingsdwellings

B.B. Brown et al. (1994). Brown et al. (1994). Measurements from new Measurements from new dwellingsdwellings

C. C. Brown et al. (1994). Measurements Brown et al. (1994). Measurements from complaint dwellingsfrom complaint dwellings

D.D. Hodgson et al. (2000). Hodgson et al. (2000). Measurements in new, Measurements in new, unoccupied manufactured homesunoccupied manufactured homes

E. E. Hodgson et al. (2000). Hodgson et al. (2000). Measurements in new, Measurements in new, unoccupied siteunoccupied site--built homesbuilt homes

F.F. Brown (2002). Measurements in Brown (2002). Measurements in nonnon--complaint, established complaint, established dwellingsdwellings

G.G. Brown (2002). Measurements in Brown (2002). Measurements in complaint, established dwellings complaint, established dwellings

H. H. Bornehag and Stridh (2000). Bornehag and Stridh (2000). Measurements in 85 singleMeasurements in 85 single--family family homes and 93 apartments in homes and 93 apartments in SwedenSweden

I. I. NorbNorbääck et al. (1995). ck et al. (1995). Measurements in bedrooms where Measurements in bedrooms where no wheezing was observedno wheezing was observed

J. J. NorbNorbääck et al. (1995). ck et al. (1995). Measurements in bedrooms where Measurements in bedrooms where wheezing was observedwheezing was observed

K.K. Wallace et al. (1991). Personal air Wallace et al. (1991). Personal air samples (N=1500) collected from samples (N=1500) collected from 600 people in six geographic 600 people in six geographic areas of the US.areas of the US.

L. L. Wallace et al. (1991). Indoor air Wallace et al. (1991). Indoor air samples (N=198) collected from 600 samples (N=198) collected from 600 people in six geographic areas of people in six geographic areas of the USthe US

5252

Residential Ventilation Residential Ventilation (Pandian, et al. 1998)(Pandian, et al. 1998)

Residential Ventilation Residential Ventilation (Pandian, et al. 1998)(Pandian, et al. 1998)

ASHRAE Standard 62.2ASHRAE Standard 62.2--20042004

David GrimsrudDavid GrimsrudChair, SSPC 62.2Chair, SSPC 62.2November 2004November 2004

5454

Purpose of 62.2Purpose of 62.2

““This standard defines the roles of and This standard defines the roles of and minimum requirements for mechanical and minimum requirements for mechanical and natural ventilation systems and the natural ventilation systems and the building envelope intended to provide building envelope intended to provide acceptable indoor air quality in lowacceptable indoor air quality in low--rise rise residential buildingsresidential buildings.”.”

Ventilation SystemsVentilation SystemsSources Sources EnvelopeEnvelope

5555

Principles Behind 62.2 Principles Behind 62.2

Occupants control their housesOccupants control their housesOccupants control sourcesOccupants control sourcesOccupants operate buildingOccupants operate building

Envelope Plays Important RoleEnvelope Plays Important RoleInfiltration and Natural VentilationInfiltration and Natural VentilationPotential Pollutant SourcePotential Pollutant Source

Sources MatterSources MatterSimple SolutionsSimple Solutions

5656

Key 62.2Key 62.2--2003 Definitions2003 Definitions

Several important definitions are covered in Several important definitions are covered in Section 3.Section 3.acceptable indoor air quality:acceptable indoor air quality: air toward which air toward which a substantial majority of occupants express no a substantial majority of occupants express no dissatisfaction with respect to odor and sensory dissatisfaction with respect to odor and sensory irritation and in which there are not likely to be irritation and in which there are not likely to be contaminants at concentrations that are known contaminants at concentrations that are known to pose a health risk.to pose a health risk.

5757

Majors Changes from 62Majors Changes from 62--20012001

Focus of standard is residencesFocus of standard is residencesRequires wholeRequires whole--house mechanical house mechanical ventilationventilationIntermittent ventilation used to control local Intermittent ventilation used to control local sourcessources

5858

ComplianceCompliance

WholeWhole--House Mechanical VentilationHouse Mechanical VentilationOr equivalentOr equivalent

Fans in Kitchens and BathsFans in Kitchens and BathsWindows in Most RoomsWindows in Most RoomsSome Source ControlSome Source Control“Good” Equipment“Good” Equipment

5959

System TypesSystem Types

Balanced SystemBalanced SystemCan have HRVCan have HRV

Exhaust SystemExhaust SystemE.g. Bath Fan UpgradeE.g. Bath Fan UpgradeCare in Humid ClimatesCare in Humid Climates‡‡

Supply SystemSupply SystemE.g. Integrated with Air HandlerE.g. Integrated with Air HandlerCare in Cold Climates Care in Cold Climates ‡‡

‡Only if Excessive

6060

Local VentilationLocal Ventilation

Intended to Exhaust ContaminantsIntended to Exhaust ContaminantsFor Rooms with Known SourcesFor Rooms with Known Sources

Kitchen, BathroomKitchen, BathroomNormally Requires Exhaust FanNormally Requires Exhaust Fan

Intermittent PreferredIntermittent PreferredWindows RestrictedWindows Restricted

Also Rooms Have Also Rooms Have Natural VentilationNatural Ventilation

6161

Kitchens and BathsKitchens and Baths

KitchensKitchens100 cfm (50 l/s) range 100 cfm (50 l/s) range hood orhood or5 (kitchen) ACH5 (kitchen) ACHExhaust onlyExhaust only

BathroomsBathrooms50 cfm (25 l/s) 50 cfm (25 l/s) capacity orcapacity or20 cfm (10 l/s) 20 cfm (10 l/s) continuouscontinuousExhaust onlyExhaust only

6262

Implementation ExampleImplementation Example

Track implementation of 62.2 in 2000 sq. ft, 3Track implementation of 62.2 in 2000 sq. ft, 3--bedroom house having 2 baths.bedroom house having 2 baths.Outside air Outside air targettarget is 90 cubic feet per minute is 90 cubic feet per minute (cfm) [60+30](cfm) [60+30]Fan Fan flowflow--raterate required is 50 cfm [20+30]required is 50 cfm [20+30]One quiet bath fan having 50 cfm capacity and One quiet bath fan having 50 cfm capacity and rated for continuous operation provides required rated for continuous operation provides required ventilationventilation

6363

Ventilation CostsVentilation Costs

Ventilation costs money in all designs. Ventilation costs money in all designs. Costs minimized when rates are Costs minimized when rates are controlled. Provide enough but not too controlled. Provide enough but not too much.much.Do not rely on infiltration.Do not rely on infiltration.Rather, use tight construction and highRather, use tight construction and high--quality fans (or blowers).quality fans (or blowers).

6464

Status of 62.2Status of 62.2

Published by ASHRAEPublished by ASHRAEPending ANSIPending ANSIProposed for Int. Proposed for Int. Residential Code (Feb Residential Code (Feb 05)05)

Users Manual RFPUsers Manual RFPDeveloping Guideline Developing Guideline DocumentDocumentAddendaAddenda

Backdrafting TestBackdrafting TestGarage?Garage???

Summary: IAQ MitigationSummary: IAQ MitigationEnormous amount of work underwayEnormous amount of work underwayTruly an American area of leadershipTruly an American area of leadership

We have a problem => fix it!We have a problem => fix it!

However, . . .However, . . .Little systematic study of mitigation occursLittle systematic study of mitigation occurs

This is a unique unexplored areaThis is a unique unexplored areaAt least, systematic studies should study the effects of At least, systematic studies should study the effects of strategies on pollutant concentrations they are attempting to strategies on pollutant concentrations they are attempting to reducereduceAt best, studies should also track health effects of building At best, studies should also track health effects of building occupants that affected by the problems that mitigation seeks occupants that affected by the problems that mitigation seeks to ameliorateto ameliorate

6666

Summary: Prevention and Summary: Prevention and Mitigation StrategiesMitigation Strategies

Source avoidance and substitutionSource avoidance and substitutionNot much in peerNot much in peer--reviewed literaturereviewed literature

No NIOSH HHERSNo NIOSH HHERS

For exampleFor exampleALA guidance for new homesALA guidance for new homes

EPA IAQ guidelines ~ Energy Star label EPA IAQ guidelines ~ Energy Star label

Finnish ventilated slabs ~ indoor RhFinnish ventilated slabs ~ indoor RhForthcoming Auburn U Forthcoming Auburn U -- EPA and UMn EPA and UMn –– MDH Rn ASD MDH Rn ASD study study

6767

Summary: Prevention and Summary: Prevention and Mitigation StrategiesMitigation Strategies

Investigation/DiagnosticsInvestigation/DiagnosticsNot much in peerNot much in peer--reviewed literaturereviewed literature

No NIOSH HHERSNo NIOSH HHERSCommunity Environmental Health Resource Center Community Environmental Health Resource Center (CEHRC) tools not found in peer(CEHRC) tools not found in peer--reviewed literature reviewed literature

For exampleFor exampleEpidemiology house characteristics questionnaires not ~ to Epidemiology house characteristics questionnaires not ~ to airborne mold concentrationsairborne mold concentrationsBackdrafting protocols need further testingBackdrafting protocols need further testing

Forthcoming residential protocol coming from AirForthcoming residential protocol coming from Air--Conditioning and Refrigeration Technology Institute Conditioning and Refrigeration Technology Institute and ASTM Subcommittee D22.05 on Indoor Airand ASTM Subcommittee D22.05 on Indoor Air

6868

Summary: Prevention and Summary: Prevention and Mitigation StrategiesMitigation Strategies

Source Containment Source Containment (Barriers & Transportation Modifications)(Barriers & Transportation Modifications)

Growing body of research ~ asthmaGrowing body of research ~ asthmaManchester Asthma and Allergy StudyManchester Asthma and Allergy StudyGraded allergen reduction (ar) & clinical (c) evidence for 32 meGraded allergen reduction (ar) & clinical (c) evidence for 32 methodsthods

metameta--analysis of randomized controlled studies = analysis of randomized controlled studies = 00one+ randomized controlled studies = one+ randomized controlled studies = 2(ar) & 1(c) 2(ar) & 1(c) controlled studies w/o randomization = controlled studies w/o randomization = 2(ar) & 2(c) 2(ar) & 2(c) well designed quasiwell designed quasi--experimental studies = experimental studies = 6(ar) & 0(c) 6(ar) & 0(c) well designed nonexperimental studies = well designed nonexperimental studies = 5(ar) & 0(c) 5(ar) & 0(c) expert opinions &/or respected clinical experience =expert opinions &/or respected clinical experience = 16(ar) & 29(c) 16(ar) & 29(c)

Did not examine <Rh as HDM or fungi control strategyDid not examine <Rh as HDM or fungi control strategy

6969

Summary: Prevention and Summary: Prevention and Mitigation Strategies Major GapsMitigation Strategies Major Gaps

Effectiveness Effectiveness Prevention guidancePrevention guidanceInvestigative & diagnostic procedures/testsInvestigative & diagnostic procedures/tests

InteractionsInteractionsVentilationVentilationRh ~ PIAQ and biocontaminantsRh ~ PIAQ and biocontaminants

Lack of mold remediation guidanceLack of mold remediation guidanceNeed Rn mitigation type field studiesNeed Rn mitigation type field studies

7070

Research RecommendationsResearch Recommendations

Residential BASEResidential BASEPublic & commercial Public & commercial building BASE studybuilding BASE study

Normative valuesNormative values

Federal Temporal Federal Temporal Indoor Monitoring & Indoor Monitoring & Evaluation studyEvaluation study

Exposure studiesExposure studiesProtocol developmentProtocol developmentCoCo--pollutants ~ health pollutants ~ health symptomssymptoms

Possible focusPossible focusBioaerosols Bioaerosols especially ~ asthmaespecially ~ asthmaNONO22 and particlesand particles

7171

Research RecommendationsResearch Recommendations

Ventilation ~ Health Ventilation ~ Health EffectsEffects

DichotomyDichotomyGuidelines to Guidelines to < ventilation rates< ventilation ratesEuropean research: European research: > asthma ~ > asthma ~ < ventilation< ventilationCompounds emission Compounds emission control effortscontrol efforts

Other gaps & needsOther gaps & needsCOCO

MaintenanceMaintenanceAlarmsAlarms

DampnessDampnessMeasurement standards Measurement standards

Mitigation/PreventionMitigation/PreventionEffectivenessEffectiveness

InvestigationInvestigationMitigationMitigationPrevention Prevention