p02 alarm. what is it?

[Devin C]

I am very new to this sport and just finished my open water. I just got my dive computer and am trying to figure it out. Could someone tell me what the p02 alarm is and what it is for. What should it be set at? I did do a search but need some more info. Thanks.

 

[ianr33]

Most recreational divers would set it at 1.4 (i.e a partial pressure of oxygen of 1.4 Atm.)

Assuming you are diving plain old air you need to be deeper than 185 ft to exceed that. In other words it is not an issue when diving air. Nitrox is a different story but thats what the class is for.

 

[sam1]

It's used when diving with Nitrox, which has a higher oxygen content than air. You set the maximum partial pressure of 02 that you want to experience, e.g., 1.4, and the computer warns you if you exceed a depth which, given the percent of O2 in your gas, would exceed the allowable partial pressure of oxygen. (The problem of a partial pressure of oxygen that is too high is oxygen toxicity, which can lead to a seizure, which can be deadly under water.)

 

[Devin C]

Yes i will be on just air. Thanks for the info.