[Aurornis]

Dissipation does not happen instantly.

I’ve done development on products with CO2 sensors and I’ve spent a lot of time with them on my desk right in front of me and also off to the side. Readings right in front of me are predictably higher.

You can breathe into a CO2 sensor 18 inches from your mouth and watch the values spike upward.

[avazhi]

I generally have fans around, but I too use a CO2 detector in my home and have tested it in various places and situations. CO2 concentrations are not as localised as you are making them out to be. If they are elevated in front of my face, for example, I can also similar numbers just above and slightly behind my head. If you go outside and do it, you’ll be surprised that the number doesn’t move really change at all when at arms’ length. Airflow is really everything here.

And, spoiler alert: if the entire area in front of you has an increased CO2 concentration, then your environment has an increased CO2 concentration. That’s the entire point.

Suffice to say I disagree strongly with both the argument that this would lead to hugely erroneous readings and also with the notion that people would panic.

[Aurornis]

> And, spoiler alert: if the entire area in front of you has an increased CO2 concentration, then your environment has an increased CO2 concentration. That’s the entire point.

I don’t think you’re reading the discussion: The CO2 thresholds that people use are based upon ambient air.

The closer the measurement to your mouth, the higher the reading will be. It should be apparent why putting the sensor directly in front of your mouth will register higher numbers than having it across the room.

CO2 does not instantly diffuse throughout a space. If it did, it would be sufficient to have only very small air leakage in a space for the CO2 to diffuse out of it very rapidly