PPO2 question for Teric owners

[WI Scuba Dave]

Hi! I have a question for you guys who own Terics and use Nitrox.

Have you noticed that what’s listed as PPO2 on the dive main screen, does not match the oxygen mix you select? For instance, if I go to Select Gas, And select a .32 mix. When I go back to my Dive screen. My PPO2 shows .31?? It’s the same with any gas mix I choose. Even regular air shows up as .20.

Is this because it’s taking my altitude into consideration or something?

Thanks in advance. I just purchased mine and trying to learn the in’s and outs.

 

[CWC]

Your guess is most likely correct. It should be showing your actual PPO2, so if you are higher than sea level it will be slightly less than the FO2. For example, when I lived in Denver and set my Perdix for air, it would show my PPO2 to be .17 or .18.

 

[Graeme Fraser]

Exactly right.

A PPo2 of 0.21b for 'air' is based on AMSL (mean sea level). If you scroll through from the main screen it will give you the SURF mBar pressure which will fluctuate based on your current altitude and / or the surrounding high / low weather system pressure.

Altimeters and other pressure gauges are usually calibrated from an accepted average of 1013 mbar so any reading deviating significantly higher or lower could push the PPo2 above or below the FO2.

 

[WI Scuba Dave]

Exactly right.

A PPo2 of 0.21b for 'air' is based on AMSL (mean sea level). If you scroll through from the main screen it will give you the SURF mBar pressure which will fluctuate based on your current altitude and / or the surrounding high / low weather system pressure.

Altimeters and other pressure gauges are usually calibrated from an accepted average of 1013 mbar so any reading deviating significantly higher or lower could push the PPo2 above or below the FO2.

Excellent! Thanks so much!!