Issue: BME680 Sensor Failure to Detect Fog in Readings

[SNAS]

Our system relies on the BME680 sensor to detect early signs of smoke . Under normal conditions, the sensor has been performing satisfactorily, promptly alerting us whenever smoke is detected in its vicinity.

However, we have recently encountered a discrepancy during testing as per the ARGE guideline, which mandates the use of a FOG machine for testing purposes. Regrettably, when the BME680 sensor is exposed to the fog generated by the FOG machine, it fails to detect it altogether.

Please guide why smoke is being detected easiliy but fog not. The fog machine utilize diesel to generate fog, it is using hot plate to generate fog through diesel on it.

[BSTRobin]

Hi SNAS,

Thanks for your inquiry.
Bosch Sensortec’s gas sensors BME680 can detect a broad range of gases such as volatile organic compounds (VOC).
Smoke is more prone to volatilization, while fog is a liquid and does not evaporate. BME680 is used for gas detection, and the detected gas needs to exchange air with the measurement unit of BME688. After a chemical reaction occurs, the resistance value is output.
What are the components of the target smoke you want to detect?