Variable Vehicle Speed (km h-1)
  32 48 64  
PM 0.5932 ± 0.2475c 1.0874 ± 0.0905b 1.888 ± 0.0656a  
  Rotorod Height (m)
  0.6 1.2 1.8 2.4
PM 4.2063 ± 0.762a 1.3264 ± 0.092b 0.6393 ± 0.109b 0.519 ± 0.302b
zMeans with the same letter are not significantly different (using Fisher’s LSD mean) at 0.05 level of significance. Bol=Bolson, Tej=La Teja, Pal=Palomas, Ant=Anthony, Col=Columbus, Dem
Table 11: Average PM measured by sticky tapes (mg/m3) for US sites at different vehicle speeds and at different heights using rotorods.