Twelve-Year Trends of PM₁₀ and Visibility in the Hefei Metropolitan Area of China

Table 1

The bottom and upper limit of API values and corresponding PM₁₀ concentrations.

API		PM10 concentrations (g m^−3)
0	50	0	50
50	100	50	150
100	200	150	350
200	300	350	420
300	400	420	500
400	500	500	600