Medical device reliability requirements

[Brian Ray]

Can anyone tell me where I can reference the following reliability requirement (in a standard, text, etc.)?

·For components that affect product safety, a reliability level of 99% shall be employed.
·For components that affect non-safety related product functionality only, a reliability level of 95% shall be employed.
·For components that affect cosmetic appearance of the product only, a reliability level of 90% shall be employed.

I know this is used in the medical device industry (and perhaps others), but I'm racking my brain and can't remember where I've seen this spelled out. I know I didn't make it up, but I need proof!

[Pantelis]

Brian – I too have seen something similar in specs but to my knowledge I do not recall seeing it in a standard or a textbook. Obviously that doesn’t mean that it’s not in one – just that I have not seen it.