Sustained Performance of Low-Cost Air Quality Sensors in Long-Term Deployments

Area of Science:

• Environmental Science
• Sensor Technology
• Air Quality Monitoring

Background:

• Technological advancements and demand for high-resolution air quality data have led to the widespread use of low-cost electrochemical gas sensors.
• While short-term sensor performance is documented, long-term reliability data for these sensors is limited.
• The Berkeley Environmental Air Quality and CO2 Network (BEACO2N) utilizes a dense network of sensors for long-term air quality measurements.

Purpose of the Study:

• To evaluate the long-term performance and reliability of Alphasense electrochemical gas sensors (NO2-B43F, Ox-B431, NO-B4, CO-B4).
• To assess sensor suitability for extended deployments in ambient air quality monitoring.

Main Methods:

• Deployment of Alphasense NO2-B43F, Ox-B431, NO-B4, and CO-B4 sensors within the BEACO2N network.
• Continuous monitoring and data collection over a 3-year period in the San Francisco Bay Area.
• Performance evaluation based on calibrated sensor data.

Main Results:

• Consistent performance was observed across the evaluated electrochemical gas sensors over the 3-year deployment period.
• Calibrated data indicated stable sensor function throughout the study duration.
• No significant degradation requiring sensor replacement was identified.

Conclusions:

• Electrochemical gas sensors, such as those from Alphasense, demonstrate reliability for long-term air quality monitoring applications.
• Appropriate calibration techniques are crucial for ensuring consistent sensor performance over extended periods.
• These sensors are suitable for prolonged use in dense, long-term air quality networks without frequent replacement.