AirGradient Forum

How Accurate is the Sensirion SGP41 TVOC Sensor?

AirGradient Blog
#1

VOCs (volatile organic compounds) are a large group of organic chemicals that easily evaporate into the air at room temperature. They have a wide range of natural and synthetic sources and can significantly impact indoor and outdoor air quality. Because some VOCs can adversely affect human health and the environment, they are often discussed in the context of air pollution and health.

This is a companion discussion topic for the original entry at https://www.airgradient.com/blog/accuracy-sensirion-sgp41/
#2

What is the approximate sensitivity for benzene? I don’t need the absolute values, but I might need to trigger an automation for as low 1-2 µg/m³. Is it expected that such low concentration is reflected in the reported VOC value in any way?

#3
#4

THis sensor isn’t specific to benzene and the values you get out of it is just an Index value that indicates change over time. So it isn’t giving any reliable measure of a concentration for any VOC, much less specific for benzene.

#5

I understand it is not specific. My question is if it is sensitive enough to change the output value if the benzene concentration changes from a long time average of zeroish to approx. 1-2 µg/m³.
(I understand that if the output changes that can be because of the change in concentration of any VOC, so it doesn’t mean that benzene has changed. In my use case that is perfectly fine, I am OK to have any ammount of false positives)

#6

I don’t have that information, and we don’t have a reference instrument for Benzene so we can’t test this. But it awould be interesting to know, so let us know if you find something out.