This looks like a very cheap attempt at a vaguely medical symbol, but actually is neither one thing nor another. I would worry that your manometer is a Chinese rip-off product of a genuine article.
The classical emblem of medicine is the
Rod of Asklepios, a staff with one snake coiled around it. It is commonly mixed up with the classical emblem of the Greek god Hermes, who had a winged staff with two entwined snakes known as the
Caduceus - the emblem of commerce.
This confusion has almost completely taken over, so many medical devices and organisations use the Caduceus as their emblem. Two snakes are better than one?
It also gets confused with many of the Biblical myths around the miracles of the old prophets, turning snakes into sticks or vice versa, or medically respected people using control of snakes as a sign of their power.
The only true recognised symbols that should be on medical devices are in ISO 15223-1:2012. Unfortunately, they expect you to buy the standard at 86 Swiss Francs to find out what you should expect (or not, as the case may be) to see on your equipment!
However, I did find a page where someone has scanned in the most important everyday symbols that should be on there. See
Medical Symbols to EN 980 or ISO 15223-1:2012 Hope this is useful to you.
