I am fairly new to this air quality monitoring and i was unaware as to how the air quality fluctuates from green to yellow to red every couple of days. Does anyone know what is causing this? I notice that i feel better on the green days. I love having the monitor mounted to my shed to where i can wake up and see the color of the leds indicating the air quality for the day.
Hi Joe,
Air quality can fluctuate from day to day and even throughout the day due to weather patterns, wind, wildfire smoke (including smoke from fires far away), traffic, dust, and other routine activities. The location of the sensor is also very important. I oversee several PurpleAir units throughout our region, and care is taken to place them away from generators, exhaust outlets, HVAC equipment, and other nearby sources that could affect readings. Surrounding land uses, such as farms or dairy operations, can also influence air quality levels at times. Fluctuations like this are expected and don’t necessarily indicate a problem, just normal changes in local air conditions. That said, ongoing monitoring and basic maintenance are important, as sensors can become dirty over time and provide inaccurate readings or stop working properly. I recently cleaned one of our units that was showing unusual readings and a red indicator, and once cleaned, it returned to normal operation.
Hope this information is helpful!
Thank you for replying. I am also using an app called Windy where they have an air quality map that shows blobs or fronts of poor air quality that are floating all around the world and they also forecast on a slider what the air quality will be out 3 days and its fairly accurate. It seems that there is more to this than some local source as it is coming from far away and for some reason it intensifies at different moments and can stay for long periods or move out quickly. How can they forecast this and whats in the air thats making it dirty and its coming from far away? My sensors reading are in line with other local sensors so its not a local source. Its these blobs of pollution that come from across the country. I am surprised at the lack of research on this. Most people are unaware of it as it is not newsworthy but i think that its more newsworthy than anything else thats on the news as these particles will circulate through your blood.