To all validation Guru's

At present I'm involved in the commissioning of an un-named endoscope washer reprocessor, this anonymous machine is a cold high-level disinfector. The question for all those students and lecturers of microbiology is has large should the cfu of pseudomonas aeruginosa be for the self-disinfection and E coli F12 for Final disinfection be? I do not mean the recovery which should be zero or 10 too the 3 reduction but the actual active colony population, 10 too the 8 or 10 too the 6. This is not to settle a large bet but a practical and I hope subjective question question.

yours Hugh O'Connor