PM values are often close to 0 (<1)

Possible causes

​​​​​​​1.The air is clean. PM are expected to be set to 0 (<1) or to show blue on the device if the air is clean.

  1. The ​sensor module filter is clogged with dust. This may happen if the device has been running for a long time in a polluted environment​.


  • Confirm that the sensor is functioning by turning off the air purifier, or by applying dust to the sensor (for example: by shaking dusty cloth next to sensor). You should see a peak in PM values after this action. ​
  • Try vacuuming the sensor module filter and test again​

If above actions do not change the status, contact the Blueair Customer Support.