Sometimes you might have a bad smell about you but not notice because your nose is used to it. A solution is the osmoperiscope. It consists of a breathing mask with activated carbon filters and a flexible hose, with a valve to switch between them. Breathe through the filters for a few minutes, and then flip the switch and put the hose end near where you suspect might be smelly. When you inhale, your nose should be used to the smell-free filtered air, so you can smell what that part of your body smells like to others. An exhalation valve in the mask allows free exhalation so that inhalation pulls air unidirectionally through the tube.

N/A [2019-04-09]
-- notexactly, Apr 10 2019

Could have two hoses, one very long, to allow comparison of two smells one near and one far away e.g. out the window
-- pocmloc, Apr 10 2019


Osmocomparator?
-- notexactly, Apr 10 2019


Could have a duplicate long hose in parallel but for your exhales so that, if you determine that you are indeed smelly, repeated exhales can be directed to destinkify the smelly parts.
-- whatrock, Apr 10 2019


But what if your breath smells bad too?
-- notexactly, Apr 11 2019



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