For a drug substance/product company,
ITs some time since the sampling procedures stopped using AQL concepts. as i had earlier described in another post...page.2
Receiving Raw Materials, Inspection, Release
supposing there are 10 tests for analysis of material...pooled sample is used to analyze all the tests and
you have to identify 1 or 2 tests which are related to identity of material and use it to analyze the samples of individual containers.
so in your example, case if you hae received 5 containers, you ought to sample all of them individually, use those individual samples for testing some specific/critical tests such as identification etc., ; and pool those samples and use that for testing rest of the paramters.
However, AQL concept of sampling and assessment is still used in packaging material analysis..
in the example you have quoted, if its applied for Packing materials, its interpretation is as follows...
you have received 5 boxes of packing materials (each one carrying 100 units of PM)
Now, you need to randomly pick up 2 boxes; and again pick up 13 samples randomly, (30-100 units --> sampling qty is 13 or 18 i don't exactly recollect)
and analyze for defects/quality attributes; YOu need to reject if you find 1 of them to be defective as per AQL.
(now this Rej=1, also depends on the AQL criteria to be selected ...)