PurpleAir are a grassroots group with a technical background that wanted to measure the pollution coming from a mining operation in our backyard. The website and map was started in November 2015. Sharing the data and our research with others created a need for more monitors, to expand the network and to test the sensors by collocating them with other monitors.
As of September 10 2017, PurpleAir has 547 sensors in operation worldwide. This number is expected to rise with further development.
These sensors match up to sensors in the 1000's of dollars so for small scale tests or for anyone wanting an idea of what the air quality is like near there home, business or school, these sensors are just for you.