Table 1 Summary of baseline housing features and PM2.5 concentrations
Sham homes (n = 16) | HEPA homes (n = 11) | p-value | |
|---|---|---|---|
Household characteristics at baseline | |||
House type (N (%)) | 0.407 | ||
Single family building | 16 (100) | 10 (90.9) | |
Townhome | 0 (0) | 0 (0) | |
Condo/Apartment | 0 (0) | 1 (9.1) | |
Building age (years, mean(sd)) | 75.75 (26.28) | 79.09 (22.68) | 0.882 |
Air conditioning type (N (%)) | |||
Central A/C | 14 (87.5) | 10 (90.9) | |
Window only | 2 (12.5) | 1 (9.1) | |
Window open frequency (N (%)) | 0.586 | ||
Never | 3 (18.75) | 1 (9.1) | |
Less than 1 day per week | 1 (6.25) | 1 (9.1) | |
2–5 days per week | 1 (6.25) | 3 (27.3) | |
6-7 days per week | 10 (62.5) | 6 (54.5) | |
Unknown | 1 (6.25) | 0 (0) | |
Pre-filter installation (N (%)) | 0.124 | ||
With pre-filter | 8 (50) | 9 (81.82) | |
Without pre-filter | 8 (50) | 2 (18.18) | |
Room volume (m3, mean(sd)) | 69.25 (27.90) | 71.56 (46.81) | 0.897 |
CADR/room ratio (h−1, mean(sd)) | 2.79 (0.96) | 2.93 (1.00) | 0.765 |
ACH (proxy, h−1, mean(sd)) | 0.76 (0.61) | 0.82 (0.46) | 0.769 |
Outdoor PM2.5 concentrations, ug/m3, mean (sd) | |||
Before Fire | 19 (10) | 19 (11) | 0.975 |
Active Fire | 48 (73) | 47 (70) | 0.827 |
Late Fire | 11 (6) | 12 (7) | 0.877 |
After Fire | 17 (7) | 18 (8) | 0.103 |
Indoor PM2.5 concentrations, ug/m3, mean (sd) | |||
Before fire | 11 (5) | 9 (5) | <0.001*** |
Active fire | 20 (23) | 17 (16) | 0.01* |
Late fire | 6 (4) | 6 (3) | 0.589 |
After fire | 9 (6) | 9 (5) | 0.540 |
PM2.5 I/O ratio, mean (sd) | |||
Before fire | 0.61 (0.25) | 0.53 (0.24) | <0.001*** |
Active fire | 0.64 (0.29) | 0.57 (0.26) | <0.001*** |
Late fire | 0.62 (0.30) | 0.63 (0.26) | 0.048* |
After fire | 0.54 (0.26) | 0.52 (0.21) | 0.234 |
