Interpreting Your Readings and Taking Action

Understanding your monitor’s readouts is just as important as using the device. Here’s a quick overview of when to take action:

ContaminantAction Threshold
PM2.5>12 µg/m³
TVOCs>0.5 mg/m³ (or 220 ppb)
CO₂>800 ppm (ventilate)
CO>9 ppm (emergency if over 35 ppm)
Formaldehyde>0.08 mg/m³ (or 65 ppb)
Humidity<30% or >60%
Radon>2.0 pCi/L (consider action); >4.0 pCi/L (mitigate)

When levels spike:

  • Turn on exhaust fans or open windows (if outdoor air is clean)
  • Run HEPA + activated carbon air purifiers
  • Avoid chemical products or stop the activity causing the spike
  • Check your HVAC system or consider bringing in a professional