BME688 - Lower and Higher detection limit for VOC in ppm unit

[salehnajafi70]

Hi.
I am trying to use a BME688 sensor to detect the concentration of VOC, but I could not find the lower and higher detection limit of VOC in ppm unit that can be measured by this sensor, and it is highly important for us.

It would be my pleasure if you could provide me with some information in this regard.

Bests,

Saleh

[BSTRobin]

Hi salehnajafi70,

The equivalent VOC output range is 0.5~1000ppm

[salehnajafi70]

Hi,

Thank you very much for the response.

As you know the Toluene is a kind of VOC gases. We exposed the BME688 sensor to the Toluene with concetration of 20 ppm, and also 1000 ppm, but the sensor was not sensitive to them. We did not see any changes to the detected concentration.

Would you please let me know BME688 sesnor is sensitive to the which types of VOCs?

Bests,

Saleh

[BSTRobin]

Hi salehnajafi70,

For your feedback "We did not see any changes to the detected concentration.", what about VOC value at that time?

[salehnajafi70]

Hi,

First, we exposed BME sensor to the indoor air and the detected VOC concentration by sensor was about 6 ppm.

Second, we exposed the BME sensor to the Toluene Gas with concentration of 20 ppm. But BME sensor still detected about 6 ppm VOC gas.

Third, we exposed the BME sensor to the Toluene Gas with concentration of 1000 ppm. But BME sensor still detected about 6 ppm VOC gas.

So we realized that is teems that BME688 is not sensitive to Toluene Gas. Beacuse as we exposed the sensor to the CO gas, the detected concentration starts to rise rapidly.