Masked Unmasked

I was busy supervising an operation being performed by a junior person. Suddenly I noticed that the second assistant had the mask in a position lower than recommended, so that the nose was open. I am quite particular about surgical asepsis and antisepsis. "Hey! Your nose is open!" I said. Suddenly three hands flew to their respective noses. I had seen only one, but three of them were breathing around the operative field through their open noses, and were fully aware of the fact. I think it is a good idea to utter this sentence in the operation theater now and then, and see how many people respond.