What does 02 -icon appearance in sleep graph mean?


Legend tells that 02 means “breathing is being measured”. But what triggers it, what special happens in breathing so that measuring starts precisely on those moments? Should I be worried on the mornings when 02 -icons are many? Noise recordings give no clues. Can’t find explanation from app sites either. Thanks.


Hi Rika,

could you please post a screenshot?
Generally what triggers breathing measurement is that we have good signal. So when you see the blue line, it means we had good enough signal to see your breath rate.
When you see that O2 icon, that means a drop in your breath rate, and if there are many of them, it might signal that something is going on with your breathing. The best way to find out is to read the RDI score that shows up in the snack bar on the bottom when you open the sleep graph’s detail.


Thanks for taking the time to answer! Here’s a screenshot. I chose a night with exceptionally many 02 -icons. And yet the RDI-score reads “normal”, ~1. That’s good I guess, but still, when you see such a long row of 02 icons it makes you wonder. Sometimes there are none, sometimes you wake up and see this… hmm :confused:


Each O2 marks a respiratory disturbance event. These are quite common during the night - you’d need about ten times more to be concerned.
Please read more about RDI here: https://sleep.urbandroid.org/documentation/extended-features/apnoe/#how-to-use-sleep-as-android-for-sleep-apnea-pre-screening