Figure 1: PM₁₀ 90th percentile of daily means vs PM10 annual mean. Data derived from UK Automatic Network sites 1992-97. (µg/m³, TEOM)
Notes
A worst case ‘best fit’ line has been applied, equivalent to the 95th percentile of the measured ratios. This gives the following relationship;
PM₁₀ 90th percentile of daily means = 1.79 PM₁₀ annual mean This compares to the regression analysis which gives the relationship; y = 1.68x, R²= 0.87

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