Table 1.
Characteristics of respiratory hospital visits and summary of daily temperature and ozone pollution in California, May to September 2004 to 2013
| Health outcome | n | Mean daily cases (SD) |
| Respiratory hospital visits | 817,354 | 677 (195) |
| Environmental exposures | Threshold | No. ZCTA days exceeding threshold for 2,863 ZCTAs |
| Heat waves (°C) | Mean ± SD | |
| Maximum temperature | ||
| 97.5th 1 d | 37.75 ± 4.11 | 69,692 |
| 99th 1 d | 38.95 ± 3.85 | 28,616 |
| 97.5th 2 d | 38.37 ± 3.98 | 34,612 |
| 99th 2 d | 39.57 ± 3.78 | 11,391 |
| Minimum temperature | ||
| 97.5th 1 d | 20.29 ± 4.21 | 69,783 |
| 99th 1 d | 21.27 ± 4.22 | 28,679 |
| 97.5th 2 d | 21.08 ± 4.00 | 33,394 |
| 99th 2 d | 22.10 ± 3.88 | 12,105 |
| Ozone waves (ppb) | ||
| 99th | 79.92 ± 15.36 | 23,126 |
| 95th | 71.58 ± 15.00 | 110,122 |
| 90th | 67.49 ± 14.87 | 217,272 |
| 75th | 61.67 ± 14.41 | 534,519 |
| 70 ppb | 78.07 ± 7.81 | 187,227 |