BME680 Gas Sensor Accuracy for VOC

[pennygoesaround]

I have a question regarding the VOC accuracy. I was looking online, it seems that there is a variable called BSEC_OUTPUT_BREATH_VOC_EQUIVALENT that will give me the concentration VOC in ppm. Assuming I am interested in measuring the concentration of ethanol (2 ppm at most), what's the accuracy of the measured value? 

In the data sheet, it mentions Sensor-to-sensor deviation +/- 15% +/- 15. Does it mean the accuracy of the measused VOC concentration will be BSEC_OUTPUT_BREATH_VOC_EQUIVALENT*0.15 +/- 15?

[FAE_CA1]

Hi,

Thanks for your inquiry.

In BME680 datasheet the typical IAQ deviation from sensor to sensor is +/-15% +/- 15. The IAQ value [0, 500] is the output of BSEC library. If the reference meter shows IAQ of 200 for example, then the IAQ error from BSEC should be in the range of [-45, +45] which means that the IAQ output of BSEC should be in the range of [155, 245].

The accuracy of bVOC which is another output of BSEC in the range from 0.5ppm to 1000ppm is not defined or specified.

Thanks.