The statistical analysis shows that there is no
difference between the average concentrations obtained by passive
samplers and continuous monitors; the linear regression results show
that there is good agreement between the two methods (R=0.9473,
pb0.0001). The accuracy of passive samplers for SO2 ranged between
2.4 and 11% in the concentration range of 2.8 to 20 μg m−3 in
industrial area, and 4.0–10% in the concentration range of 1.9–
3.0 μg m−3 in urban area.