Frient Air Quality Sensor AQI issues

opening this chat to discuss differences in AQI measuring methods. My Frient Air Quality sensor (in EMEA) running on hubitat c7 device firmware * firmwareMT: 1015-0320-00040001 , hubitat version: ** seems showing out of range data (sometimes 18< for AQI.) After posting in many groups , hubitat driver creator suggested to open a separate topic to discuss this.