What are the air pollution index levels? When the air pollution index is lower than what, even if the air quality is excellent? What are the air pollution index levels? What about level seven

What are the air pollution index levels? When the air pollution index is lower than what, even if the air quality is excellent? What are the air pollution index levels? What about level seven

The air pollution index is divided into seven grades: 0-50, 51-100, 101-150, 151-200, 201-250, 251-300 and more than 300, which correspond to seven grades of air quality. The higher the index is, the higher the grade is, indicating that the more serious the pollution is and the more obvious the impact on human health is