I am using the DSM501 Dust and Particle sensor for the first time with code from Calculate the Air Quality Index (IAQ, IQA) with a DSM501 on Arduino or ESP8266 • DIY Projects.
I am getting some values for PM 2.5 and 1.0 but am not sure how accurate they are. For example, my dad uses a air purifier in Delhi and when it is turned on it shows 120 or 150 say, and then after running some time the values come to under 30 or so.
My setup seems to show AQI values like 15, 25, etc in a room without any cleaning of course. how do i know the value is correct? It is my first time with this sensor so i am using the code from that link there directly (setting country to 2). On the website aqi.in it says 200+ in the area (outside)