That's exactly what I'm looking for, looks like I can get a $30 MQ131 with detection a range of 10PPB-2PPM [1], and a "Good" indoor level is 0 - 54ppb [2]. It

That's exactly what I'm looking for, looks like I can get a $30 MQ131 with detection a range of 10PPB-2PPM [1], and a "Good" indoor level is 0 - 54ppb [2]. It doesn't need to be super accurate for my use case, basically I just want to turn on the electronic filter and see if there are any detectable levels of Ozone. [1] https://www.sainsmart.com/products/mq-131-gas-sensor-ozone-module https://www.sainsmart.com/products/mq-131-gas-sensor-ozone-m... [2] https://learn.kaiterra.com/en/resources/ozone-what-levels-are-safe https://learn.kaiterra.com/en/resources/ozone-what-levels-ar...