Table 3:

Distribution of drive-average (2 hour duration) pollutant measurements. Drives had on average 815 measurements (at 10 second frequency) each resulting in a single ~2-hour average. Pollution data was available for 37 of the 39 drives in the analytic sample. Note that the standard deviations correspond to the distribution of 2 hour averages, and not for measurements at the raw sampling frequency.

	Unfiltered		Filtered
	Mean (sd)	Median (IQR)	Mean (sd)	Median (IQR)
PNC (per cm3)	25204.6 (8740.8)	23648.3 (18790.6, 29758.5)	3405.9 (1824.9)	3023.5 (2289.4, 4086.9)
PM2.5 (μg/m3)	8.7 (4)	7.7 (6.9, 8.9)	3.5 (0.6)	3.4 (3.2, 3.5)
BC (μg/m3)	2.8 (1.3)	2.9 (1.9, 3.6)	0.4 (0.3)	0.3 (0.2, 0.4)
NO2 (ppb)	22.9 (5.1)	22.9 (19.2, 26.2)	18.6 (4.4)	19.4 (15.5, 20.6)
CO (ppm)	1.7 (0.8)	1.5 (1.2, 2)	2 (1)	1.8 (1.5, 2.3)
CO2 (ppm)	1314.4 (282.8)	1269 (1215.1, 1387.1)	1491.2 (534.3)	1374.9 (1115.9, 1724.3)