AirGradient Forum

Do AirGradient PM2.5 Monitors Stay Accurate Over Time? We Found Out!

Low-cost PM2.5 sensors are increasingly used for long-term air quality monitoring because they are affordable, easy to operate, and capable of delivering continuous, high-resolution data without the need for on-site maintenance. Their main limitation, however, is reduced accuracy compared to regulatory instruments, which, in turn, raises questions about their stability and the frequency of calibration required. A common concern is whether these sensors experience drift – a gradual change in response over time that could compromise data reliability. We decided to investigate to see if PM2.5 drift is something you need to worry about with your AirGradient monitors.


This is a companion discussion topic for the original entry at https://www.airgradient.com/blog/do-our-pm2.5-sensors-drift/

What are the legend entries in Fig. 3?
The first graph (out of four) has a legend, but the other three do not.
Do the other three use the same colors? If so, the reference device seems missing, making them look like inter-correlations among 2 AirGradient units without a reference. Or perhaps they show average of 2 AirGradient values compared with the reference. In any case, adding a legend would help clarify this.
Thanks

Hi @Akila! The R squared, RMSE and slope are relative to the reference so the reference isn’t included in those 3 charts. I’ll forward your feedback!

Thanks. The question is about the colors in the lines. And a possible confusion / mix-up. Same colors used in the plot 1, but with a different meaning or something I think!

Have any insight into the stability and lifespan of the gas sensors?