Dear Wayne,
You have certainly raised a very realistic issue. Evaluation of Perfomance Objectives depends very much on the validity of the data implementation for Performance Analysis.
Base on your argument, the Performance Criterion seems uncertain with regards to the setting of an acceptable microbiogical sampling plan when "c" is "0" as you have rightly argued so that the proliferation rate of a bacterium is never static unless the test environment is controlled which in this case is almost always dynamic unless based on lots of assumptions as Charles C. has pointed out. So indeed, can "c" be "0".
Again, I like to stress Charles C.'s reminder of ISO 17025 test methodology as an important benchmark for .........
By the way, I think your Engineering Food Audito Mate should seriously reconsider about food auditing.
Regards
Charles Chew
Dear Charles C & Charles Chew
After reading this thread in the forum, my engineering food auditor friend has make a firm decision
not go ahead with the audit of ISO22000 system even though his CB has registered him to be the lead food auditor.
He admitted that microbiological risk assessment is not as simple as what he has originally thought of; it is a complicated system. He was surprised that the authority has given him the ticket to audit ISO22000 even though he was (is) technically not qualified.
However, I encourage him not to give up but to take up a course in food microbiology or a similar field. My engineering mate wants to thank both Charles for awakening him or else he would have committed a professional crime.
Charles C, I do share with your feeling as being an auditee. Indeed, I was being audited by an "extra large international company" two days ago. I do understand your feeling as an auditee? Some auditor(s) are behaving as they were "above the law of the land" even though it doesn't make any sense out of it (i.e. with little scientific ground).
It is sad to see that some laboratories with ISO17025 capability are
NOT better than those without ISO17025; their work/ reports are crap. Charles C, do/did you have similar experience in this? This again, ..... ( perhaps it is the quality work of an auditor, not my mate this time).
I have to rush off to the bush again and will be back in a couple of days. I will talk to you both soon. Take care.
Simon, would it be nice if more technical members can / are willing to make contribution to this topic? We need this to safe more life in our community.
Kind Regards
Wayne