Swab alert limits and mean contaminationrecovery rates

Hi. I’m looking at USP 36 [1116] for surface sampling where they talk about mean recovery rates for the different ISO classifications. I’m referring to an ISO 7 area which according to USP has a recovery rate of 5%. My question is - what does this actually mean. Do I swab a piece of equipment a number of times, this then gives me my theoretical “bioburden” for that piece of equipment, and if 5% of my samples fall above this number then I need to re-evaluate the cleaning regime. I ask this as I cannot find alert and action limits for swabs for ISO 7 areas. HELP

Wrong version of the USP! In order to be current you should be reviewing USP 40 (you’re behind the times by several years), soon to be version 41.

Fair enough.
My question still stands though.