Does anybody know what are the requirements for acceptable cleanliness/bioburden on a medical device that is not sterile? The device in question is a breathing tube for a ventilator that does not need to be sterile. My understanding is that I need to determine the cleanliness level in the risk analysis and then create a spec but I am not sure if there are any standards or guidance for the required cleanliness level. How do I go about what level of clean/bioburden is acceptable? Your feedback is much appreciated!