Is a tracheostomy tube holder exempt from biocompatiblity testing requirements simply because it does not require a 510(k)?
IMO, Exemption from the requirement to submit a 510(k) notification to FDA is limited to just that. You don't have to submit a notification to FDA. It doesn't exempt you from anything else, including, IMO, the need to have data showing substantial equivalence to another legally marketed device that is exempt from the requirement to submit a 510(k) notification to FDA. I don't think it is a device that is exempt from anything just because you say so. It has to be SE to another device that is exempt from 510(k) notification, or it has to have been classified as 510(k) exempt device via De novo.
Regardless, like all medical devices regulated by FDA, it is subject to general controls. IMO, if it is dangerous to health, it is misbranded, and, if you haven't established biocompatibility, you don't know if it is dangerous to health, so a claim that it is safe for its intended use is false and misleading.
General Controls for Medical Devices
I repeat IMO a lot here because I'm not sure even FDA knows what it thinks about all of this. I don't know that it's had enough exposure to devices claiming to be 510(k) exempt to have even developed an opinion. Especially an informed opinion. What I'm pretty sure of? If a device the manufacturer claims is 510(k) exempt causes problems due to a lack of biocompatibility, and the manufacturer never evaluated it for biocompatibility, FDA will quickly develop a very strong opinion about that particular device and manufacturer.