Table 4:
Associations between the degradation outcomes (% of flagged measurements and correction error) and year of operation of the PurpleAir sensors. Note that we did not have any PurpleAir sensors collocated with a regulatory monitor in Sub Arctic and Cold Climates. In addition, all PurpleAir monitors collocated with regulatory monitors were outdoor.
| Associations (95% Confidence Interval) | ||
|---|---|---|
| Dataset | Percentage of Flagged Measurements |
Correction Error |
| All | 0.93* (0.91, 0.94) | −0.12* (−0.13, −0.10) |
| Device Location | ||
| Inside | −0.10* (−0.12, −0.09) | - |
| Outside | 1.06* (1.05, 1.08) | - |
| Climate Zone (Outside Devices Only) | ||
| Cold | 0.74* (0.71, 0.76) | −0.27* (−0.29, −0.25) |
| Hot-Dry | 2.09* (2.07, 2.12) | 0.08* (0.06, 0.09) |
| Hot-Humid | 0.34* (0.32, 0.37) | −0.92* (−1.10, −0.75) |
| Marine | 0.41* (0.39, 0.44) | −0.13* (−0.15, −0.10) |
| Mixed-Dry | −0.05* (−0.07, −0.02) | −0.31* (−0.40, −0.21) |
| Mixed-Humid | 0.54* (0.51, 0.57) | −0.28* (−0.33, −0.23) |
| Sub Arctic | −0.18* (−0.22, −0.14) | - |
| Very Cold | 0.13* (0.10, 0.16) | - |
*
p<0.05