Aeroqual released a direct-read NO2 module in December 2019 for the AQS 1 and AQM 65 monitors. This module replaced the previous approach that used an Ox module in combination with an O3 module to measure NO2.
Key benefits of the new module design include:
- Only a single module needed to measure NO2
- Improved detection limit, drift, precision and linearity when compared to the previous Ox/O3 system
- Improved baseline stability
- Easier calibration.
The direct-read NO2 module uses the medium-size module design. This is the same as the Ox module it replaces. You can confirm the module you’re using by checking the barcode label on the actual module, or by checking the sensor list in Aeroqual Connect or Aeroqual Cloud. If you have an Ox module fitted, Ox will appear in the Active Sensors list in the Configure app.
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| New NO2 module | Old two module design (Ox and O3) |
The direct-read NO2 module includes integrated scrubbers, a solenoid to switch between the measurement and zero cycles. It also features an electrochemical NO2 sensor and a printed circuit board for controlling the module.
The module’s scrubber and ozone filtering system have a finite lifetime, but this is expected to be greater than the life of the sensor under most circumstances.