*This unofficial 1-hour index was derived from the PM
2.5 AQI levels, which are based on a strong body of epidemiological evidence associating 24-hour PM
2.5 exposures with respiratory and cadiovascular morbidity and motaility. For more information on the 1-hour AQI index, follow
this link.
**U.S. EPA 24-hour National Air Quality Standard (NAAQS) of 35 µg/m
3. This value is based on the most recent 24-hour rolling average.