Quality assurance validation testing is performed on data generated from PurpleAir and Clarity sensors before the is data published on AirVisual.
The data obtained from these sensors is cross referenced to data from government operated monitors, as well as other low cost sensors in the same vicinity.

This improves the accuracy and precision of the data found on our website by accounting for issues like hyperlocal pollution sources (like smoke from a neighbor's BBQ) so it does not artificially impact the air quality data for a larger area.

We have also added calibration methods based on environmental conditions to improve the accuracy of the data provided by the PurpleAir sensors.
This decreases the likelihood of hyperlocal sources (i.e. someone grilling outside) impacting the data for the area.

Learn more about how our sensors calculate this data below:

https://www.iqair.com/support/knowledge-base/what-is-aqi

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