Here is the bVOC range: 05 - 1000 (ppm), but bVOC would 0.5 when the stationaryIAQ = 25 and it would be 15 ppm when the stationaryIAQ = 250.
If stationaryIAQ is lower than 25, bVOC could be lower.
And CO2 range is 400 ~.. (ppm)
Basically, default IAQ value shall be 25. I think you are talking about IAQ accuracy?
Please check one more time.
And could you let me know where you get your test code?
Officially, we have BSEC library as below.
And BME68x as below.