1 - Home | Colorado.gov

Relative Percent Difference Equation: Absolute value (Sample 1(S1) – Sample 2(S2)) / ((S1 + S2)/2) * 100 = RPD. A 5% collection of a field duplicate are required for chemical parameters, which is a minimum of 1 duplicate per 20 samples or 1 sample per sampling event if less than 20 samples. ................
................