Health and Environmental Aspects Linked to Home Ventilation (HEALTH-V Study) -Preliminary data

Transcription

1 Health and Environmental Aspects Linked to Home Ventilation (HEALTH-V Study) -Preliminary data Dave Jacobs 1 2, Salvatore Cali, 1 Loreen Targos 1, Paul Francisco 3, William B. Rose, Zachary Merrin 3, Steve Nall, 4 Dan Phillips, 4 David E. Jacobs, PhD, CIH 1,2 1 University of Illinois at Chicago (UIC) 2 National Center for Healthy Housing 3 Illinois Sustainable Technology Center, University of Illinois at Urbana-Champaign (UIUC) 4 Indiana Community Action Association, Inc. (INCAA) Presenter contact: dejacobsdc@gmail.com

2 Purpose of study Look at impacts on health & IAQ associated w/ 2 residential ventilation protocols for weatherization in low-income housing. Study compares IAQ in pre- & post-weatherization with ventilation determined by ASHRAE relative to ASHRAE. WHO concluded there is insufficient evidence on ventilation and health outcomes 2

3 Two protocols ASHRAE : 15 cfm fresh air/ occupant; Building Tightness Limit (BTL) for infiltration derived from blower door test at 50 Pa depressurization. If infiltration is enough, no mechanical or additional ventilation needed. In practice, many agencies use(d) BTL as air seal limit guide to avoid mechanical ventilation. ASHRAE : Target is 7.5 cfm fresh air/ occupant plus 1 cfm/ 100 ft 2 floor area. Usually mechanical ventilation needed. Effective BTL much leakier than with. 3

4 Test two hypotheses: Purpose of study 1) Using a ventilation protocol in weatherization improves health & indoor environment conditions; and 2) Adopting ASHRAE results in significant health & indoor environment improvements compared with ASHRAE. Randomized Controlled Study Design Timeline Control Group Study Group Baseline Postintervention No Mechanical Vent (n=42 units) ASHRAE (n=42 units) No Mechanical Vent (n=42 units) ASHRAE (n=42 units) 4

5 Methods & materials Participants recruited through 2 low-income home weatherization programs (CEDA and INCAA), approximately 84 homes total (n=84). Environmental samples collected for 1-week (range 4-7 days) intervals before and after weatherization. Health interviews collected at baseline & approximately 6 months after weatherization 5

6 Methods & materials Collection of routine & some extra weatherization assessment data, including: Size of home Zone pressures Duct tightness Pre- & post weatherization (Wx) blower door tests Mechanical equipment # of occupants Insulation levels 6

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9 Methods & materials 1-week interval air sample tests, pre- & post weatherization, using: Passive air sample badges for formaldehyde (SKC UMEX-100) Passive air sample badges for total volatile organics (TVOCs) (3M 3520) Radon charcoal cans (Accustar diffusion barrier charcoal canisters) placed in 1 st flr LR & basement 9

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11 Methods & materials Simultaneous continuous logging CO 2 (Telaire 7001 detectors & HOBO U-12 loggers) Simultaneous continuous logging CO (Lascar EL-USB-CO) Limited continuous radon measurement at least 1-week or longer as possible (AccuStar Continuous Radon Monitor RadStar RS300) Continuous logging temperature & relative humidity (LASCAR - EL-USB-RT T/RH/DPt USB) Samplers placed in LR; additional T/H datalogger & radon canister placed in basement if present 11

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13 Formaldehyde Number (N) Preliminary results Min (ppb) Formaldehyde Max (ppb) Mean Median (ppb) (ppb) Geomean (ppb) all all T-test Wilcoxon signed rank test < P < < P < < P < 0.02 Yellow indicates statistical significance ; 0.05, 2-tailed tests RPD of Geomean -11% -9% -13% 13

14 TVOC Number (N) Preliminary results Min Max TVOC Mean Median Geomean all all T-test Wilcoxon signed rank test RPD of Geomean P > % P > % < P < % Yellow indicates statistical significance 14

15 Radon 1st flr Number (N) Preliminary results Min (pci/l) Radon, 1 st floor Max (pci/l) Mean (pci/l) Median (pci/l) Geomean (pci/l) all all T-test Wilcoxon signed rank test RPD of Geomean P > 0.2 5% < P < % P > % Yellow indicates statistical significance Radon concentrations truncated at reporting limit of 0.4 pci/l / square root of 2 15

16 Radon basement Number (N) Preliminary results Min (pci/l) Radon, basement Max (pci/l) Mean (pci/l) Median (pci/l) Geomean (pci/l) all all Yellow indicates statistical significance T-test Wilcoxon signed rank test < P < 0.10 RPD of Geomean 22% P > % < P < 0.20 Radon concentrations truncated at reporting limit of 0.4 pci/l / square root of %

17 CO average Preliminary results Carbon monoxide (CO) average Number (N) Min Max Mean Median Geomean all NA 63 all NA NA NA NA NA Yellow indicates statistical significance T-test Wilcoxon signed rank test RPD of Median P > 0.2 0% P > % P > % 17

18 CO max Number (N) Preliminary results Carbon monoxide (CO) maximum Min Max Mean Median Geomean all NA 63 all NA NA NA NA NA Yellow indicates statistical significance T-test Wilcoxon signed rank test RPD of Median P > 0.2-8% P > % P > % 18

19 CO2 average Preliminary results Carbon dioxide (CO 2 ) average Number (N) Min Max Mean Median Geomean all all T-test Wilcoxon signed rank test < P < 0.02 RPD of Geomean -13% P > 0.2-9% < P < % Yellow indicates statistical significance Carbon dioxide concentrations truncated at detector high concentration limit of 2500 ppm 19

20 CO2 max Preliminary results Carbon dioxide (CO 2 ) maximum Number (N) Min Max Mean Median Geomean all all Yellow indicates statistical significance T-test Wilcoxon signed rank test < P < 0.02 RPD of Geomean -11% P > 0.2-7% < P < % Carbon dioxide concentrations truncated at detector high concentration limit of 2500 ppm 20

21 Confounders for evaluating IAQ in single-family homes Seasonal & meteorological conditions House variables (many characterized in weatherization assessment data) Source strength & location Utilization & performance of combustion sources Occupant activities, furnishings Limitations of environmental tests 21

22 Leakiness as estimated by blower door test air flow rate -50 Pa) ASHRAE ASHRAE Blower house zone-closed test pre-wx (cfm) Blower house zone-closed test post- Wx (cfm) average 3,189 2,292 median 3,115 2,150 average 3,349 2,404 median 3,281 2,104 Study home floor areas (ft 2 ): CEDA: 768 2,482, avg 2,030 INCAA: 1,120 4,336, avg 2,092

23 Preliminary results: Correlation estimates for blower door test air flow rate -50 Pa) & indicator concentrations CEDA homes only, significant correlations only Regression statistics R 2 Spearman test statistics Spearman's rho Formaldehyde post-wx CO max post-wx CO2 avg post-wx CO2 max pre-wx CO2 max post-wx Green indicates not quite significant Yellow indicates statistical significance 23

24 Preliminary results: Correlation estimates for blower door test air flow rate -50 Pa) & indicator concentrations Correlation w/ leakiness as measured by blower door test exists, but weak

25 Preliminary Health Interview Findings Variable Before After P-value Water/dampness 65% 29% <0.001 Pesticide use 60% 37% Child Headaches 32% 13% Respiratory allergy 23% 14% Chronic Bronchitis 19% 12% Comfort Hot/cold 53% 74% Adult General Health Child General Health Satisfaction %

26 Overall summary Statistical analyses (at 95% confidence) for pre- and post Wx tests, indicate: Formaldehyde: concentrations significantly reduced in All (both protocols) group & in ASHRAE group TVOC: No statistically significant change Radon 1 st floor: No statistically significant change Radon basement: No statistically significant change Carbon monoxide (CO) avg & max: No statistically significant change Carbon dioxide (CO 2 ) avg & max: concentrations significantly reduced in All group & in ASHRAE group 26

27 Discussion/ Conclusions Weatherization-related interventions resulted in significant reductions from baseline for formaldehyde and CO 2 ; Other contaminants did not change significantly ASHRAE ventilation may perform significantly better that ASHRAE These preliminary results suggest ASHRAE provides better IAQ in living areas relative to baseline and 27

28 Further analyses to be performed Health interview responses Modeling for hygrothermal effects in 1 st floor & basement using ISO Climate Class approach Multi-variate analysis & modeling of indicator results, controlling for confounders & effect modifiers (e.g., season, location, type of house, etc.) 28

29 Acknowledgements & Disclaimers This project supported by U.S. Department of Housing & Urban Development (HUD Grant Number: ILLHH ), & some researchers were partially supported by National Institute of Occupational Safety and Health (NIOSH) Training Grant Number T42/OH The contents of this presentation are solely the responsibility of the authors & do not necessarily represent the official views of HUD or NIOSH. The Health-V (Health and Environmental Aspects Linked to Home Ventilation) Study received UIC Internal Review Board approval for research involving human subjects. We thank Eugene Pinzer (HUD), Jill Breysse, Sherry Dixon (NCHH), Harold Dawson (CEDA), Steve Nall, & Dan Phillips (INCAA) for their help on this project. 29