The air quality index explained: What air quality is bad?

Purple Air AQI Display

AQI Visualizer

The Air Quality Index (AQI) Basics & Beyond | Lane Regional Air Protection Agency

SOLVED: 1.38 Air quality Daily air quality is measured by the air quality index (AQI) reported by the Environmental Protection Agency. This index reports the pollution level and what associated health effects might be a concern. The index is calculated for five major air pollutants regulated by the Clean Air Act and takes values from 0 to 300, where a higher value indicates lower air quality. AQI was reported for a sample of 91 days in 201 in Durham, NC. The relative frequency histogram below sh

What is the Air Quality Index?

Overview of Air Pollution from Transportation | US EPA