I found a very interesting air quality sensor board from the Germany company OhmTech on Tindy. One of this magic Bosch Sensortec sensor - the BME680 - is used in conjunction with an STM032F72 microcontroller to give a neat "USB-sensor-stick":
The BME680 contains an barometric sensor with an amazing resolution of abt. 100cm, a high resultion temperature and humidity sensor and last but not least a gas sensor. All the sensor data is used for data fusion and transformed into an indoor air quality (IAQ) index.
To get the sensor data into my data I wrote a small JAVA application to query the USB-sensor via the emulated serial port and push it to my MQTT server. The JAVA code can be found on my GITHUB repository.
The sensor sensitivity is amazing. Inside my abt 16m2 lab using a wet cleaning cloth from ALDI to wipe an area of 1m2, creates an instant sensor response: