I was idly wondering about this recently, so I thought it would be fun to make a market out of it.

Potentially relevant info:

• On average, about a third of my working hours are spent in a wet lab.

• I'd estimate that I drink about 56 fl oz (mainly water) per day.

• I strongly prefer to wash my hands over using hand sanitizer.

My personal guess is around 12, but we shall see...