When looking to purchase sensors, it is possible you might wonder how many sensors would be appropriate for your space. To determine this, you’ll probably want to consider a PurpleAir sensor’s coverage area.
Sensor Coverage Area
PurpleAir sensors are only able the measure the air physically pulled into the them (roughly a 2-inch by 2-inch area) by their fans This means you should think of data from a sensor as representing the particulate matter (PM) at a particular point, rather than an entire area. The more points (or sensors) you have in an area, the better spatial resolution of PM you will get in that area.
Since air quality is a complex issue and unique to each location, it can be difficult to determine how many sensors an area needs or where to place them. To explore this on your own, you can search for areas of comparable size and desired coverage on the PurpleAir map, and get an idea of how many sensors you may need. Other things to consider are localized sources of air pollution, weather patterns (i.e. predominant wind directions and wind speed), and local points of interest such as hospitals, libraries, schools, parks, etc.
Learn More
Off the Grid
PurpleAir Sensors Functional Overview
What Do PurpleAir Sensors Measure and How Do They Work