Fig. 3. Sampling to comply with a maximum pest limit, based on the risk to the importer. The dashed line (  ) shows the probability that a consignment is above the maximum pest limit after treatment 1Pr(B) as a function of the proportion of fruit infested p, with:
and q = N × µ × s × h × p; m=3, N=208550, µ=40, s=10^{4.5}, h=1, data from Cannon (2). The dotted line () shows the probability that the pest is not detected in the sample Pr(A) as a function of the proportion of fruit infested p, with Pr(A)=e^{np}. The sample size n is chosen so that probability that a consignment is above the maximum pest limit after treatment and that the pest is not detected in the sample [1Pr(B)]×Pr(A) (shown as a solid bold line) has a maximum value of , with =0.05 in this case.
Image from Plant Health Progress article:
The Maximum Pest Limit Concept Explained
