Why doesn’t my data look right?

Typical issues which can cause data from AQMesh to not look as expected when comparing it to reference are as follows:

  • Phase shift
    • This can be a large difference due to time zone differences, or small due to drift from internal clocks on reference instruments
  • Units of measurement
    • AQMesh reports data as standard as ppb for gases and ug/m3 for particle mass
  • Interferences
    • While every effort to compensate AQMesh for interfering gases, temperature, humidity and other environmental effects via the algorithm is done, some variation from reference, especially in the low ppb values, is possible
    • If AQMesh pods are in direct sunlight for extended periods of time, this may make a slight difference to readings
    • Reference instruments can also suffer from interferences and careful review of the instrument manual should be completed
  • Sensor change
    • When a sensor has been changed, the sensor requires a 2 day stabilisation period and 2 day rebasing period, during which data from that channel (and any related by cross gas effects) will not be valid. The invalid data will be flagged on your data file.

If you cannot see the cause of why your AQMesh data does not look correct, please refer to your local distributor, or contact us.

 

 

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