Hello, I want to use the BME688 sensor in a sauna to monitor the air quality and CO2 concentration. The main aim is to know when the CO2 concentration gets too high and when I should bring fresh air into the room. The BME688 is rated to work up to 85degC so I placed the sensor inside the sauna itself. Outside the sauna I have another CO2 sensor, rated 60degC only, with a small airpump that bring air from the sauna and acts as a reference. To simulate people in the sauna, I use a CO2 cannister from which I release some gas from time to time. Right now the CO2 equivalent I am measuring with the BME688 seems totally off and very much influenced by the temperature and humidity. I do not see any correlation with the actual CO2 level that I am measuring with my other sensor. I add some graphs of some measurements I have been doing. I also have a BME688 evaluation kit and I tried to use the BME AI software to train an algorithm to detect CO2 from different sample set I recorded. Unfortunately the gas estimate I was measuring was stuck at 33% and barely not changing, no matter what is going on in the sauna. My questions are: - How sensitive to temperature and humidity is the BME688 sensor? - Can we measure pure CO2 with this sensor? Or does the CO2 equivalent is calculated from human breath only? - Is this sensor useable at all for my use case? I am using the BSEC library version 2.2.0.0 and use lower power mode (LP) for the sample rate. Cheers. CO2 comparison Temperature and humidity
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