Figure 1From: Effects of particulate air pollution on blood pressure in a highly exposed population in Beijing, China: a repeated-measure study Measures of PM 2.5 from two independent personal monitors. Measures of PM2.5 from two independent personal monitors worn at the same time by a subset of 12 study subjects to test the accuracy of the measurements. The scatter plot shows the high correlation (r = 0.944) between monitor 1 and monitor 2.Back to article page