The following three issues struck me:

1. How much aerosolization occurs as accessories are removed from the endoscope channel while pressure is still being generated by the carbon dioxide in the duodenum?
2. How can I smell smoke while wearing an N95 mask?
3. Is this mask as good as it was when it was new now that I have worn it a few times?

The first issue, although the quantification needs to be studied, is a real thing.

The second issue has an answer—sorry, a lengthy one: