This screen works 24 hours and shows the amount of following air pollutants in Mashhad's air: CO, SO2, O3, NO2, and PM.10 (Suspend aerosols in air) and PSI (General air pollution index).
I took this photo soon in the morning of a holiday when there wasn't any congestion in the streets. I wonder why the amount of CO and PSI is high. It might remain from the last night.
آلودگی هوا، سازمان حفاظت محیط زیست خراسان رضوی