From: David Swaim
Date: 27 Dec 1999
Time: 07:41:00
The USP "zero tolerance" criteria is not easily pinned down. It is perhaps better understood as "reject the lot if any USP pathogens are found". This criteria does not mandate 100% inspection but it does require "a statistically sound sampling plan" be used. I would image that a "sound plan" would entail sufficient sampling to detect (with a 95% confidence limit) the presence of USP pathogens in the batch.