Review on GZAIR Mountable Temperature & Relative Humidity Tester for Test, Measure & Inspect, Indoor Air Quality and Airflow by Aaron Lewis

I compared this monitor to three others and found it to be very accurate right out of the box. We use it as an alarm when the level of CO2 in our house increases. In this age of Covid, keeping below 600 means we're not breathing air. A study in Taiwan showed that keeping CO2 levels below 600 can stop a TB outbreak. This can be an indication of the benefits that come from maintaining adequate air exchange rates in our homes and schools.