Variable --------------------Vehicle Speed (km h-1 )--------------   32 48 64 PM2.5 T11 4.5191bz 5.5914b 7.6613a PM2.5 T52 2.2379b 3.5369ab 4.5953a PM2.5 T103 1.0883a 1.0868a 1.7526a PM2.5 T154 0.5603a 0.5873a 0.7987a PM2.5 T205 0.2998a 0.4736a 0.5363a PM2.5 T256 0.1334a 0.3170a 0.3747a PM2.5 T307 0.03214a 0.04767a 0.16937a PM2.5 Sum8 8.872b 11.641b 15.740a zMeans with the same letter are not significantly different (LSD mean) at 0.05 level of significance Difference between vehicle speeds on average: 1(1.07, 2.07); 2(1.3, 1.06); 3(0, 0.66); 4(0.03, 0.21); 5(0.17, 0.06), 6(0.18,0.06), 7(0.01, 0.12), and 8(2.77, 4.1)

Table 8: Average particulate matter (PM2.5) (mg/m3) detected by the DustTrak for three vehicle speeds 1 to 30 seconds after the vehicle passed in front of the instrument.