In scuba diving, one has to constantly monitor a few parameters, such as
2. diving time
3. air pressure left in the bottle.
A device showing at least depth and diving time with visual alarms would be extremely uselful and a great improvement for safety:
I found myself in a couple of situations (lost my buddy) when I got distracted from keeping an eye on the depth meter and not hearing the sound alarm from my depthmeter. Indeed the noise of the bubles when breathing heavily under stress was loud... And I entered the danger zone... this could have been dramatic if it lasted a bit longer...
I believe such an instrument should not be too complex to introduce in a scuba mask without the necessity to run anything through as the pressure inside the mask is in general the same as outside the mask...
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