Table 2.
Summary of average PM2.5 levels and cigarette consumption time by condition
| Mean PM2.5 at baseline (μg/m3) |
Mean PM2.5 exposure (μg/m3) |
||||||
| Condition | Before | After | Prior to lit cigarette | During cigarettea | Two minutesb | Mean peak (μg/m3) | Mean cigarette time (min) |
| 1 | 14.7 | 15.8 | 13.4 | 3,850.9 | 4,377.5 | 6,590.5 | 7.5 |
| 2c | 15.1 | 16.3 | 16.6 | 2,412.5 | 1,729.6 | 3,781.0 | 7.9 |
| 3 | 14.1 | 15.0 | 13.7 | 60.4 | 26.3 | 142.1 | 5.9 |
| 4d | 14.3 | 15.4 | 13.2 | 222.5 | 91.3 | 382.1 | 6.6 |
| 5c | 15.1 | 14.4 | 16.0 | 844.4 | 470.3 | 1,249.7 | 7.3 |
Note. aRefers to the time period in which the cigarette was consumed.
b
Two minutes after the start of the cigarette.
c
Mean of 17 car monitoring sessions, one car excluded due to relighting of cigarette.
d
Mean of 17 car monitoring sessions, once car excluded due to machine failure.