How many of you have failed to analyze a tank that you thought had air?

[scubadiver888]

I never use tank of air for calibration for the reason stated by you above. I just use ambient air.
No we do not have to trust anyone including ourselves Analyzing the tank before the dive removed that necessity of trusting anybody.

Are you adjusting the sensor based on the temperature and humidity levels? I have yet to see a shop with a hygrometer and most do not have a scientific thermometer. If you set it to 20.9 for ambient air in Toronto then it is most likely wrong.

 

[elan]

I do, my setting usually ends up being 20.6-20.7. Deviation of few tenth of % is not a big deal given the precision or lack thereof of the sensors. It's definitely better than calibrating against a tank with God only knows what's inside content.

Are you adjusting the sensor based on the temperature and humidity levels? I have yet to see a shop with a hygrometer and most do not have a scientific thermometer. If you set it to 20.9 for ambient air in Toronto then it is most likely wrong.