Air Quality

Air Quality

The National Oceanic and Atmospheric Administration (NOAA), in partnership with the Environmental Protection Agency (EPA), issues daily air quality forecast guidance as part of a national Air Quality Forecasting Capability. NOAA’s National Weather Service (NWS) currently provides forecast guidance for ozone and smoke based on numerical atmospheric predictions updated twice daily. read more …

Air Quality Forecast Guidance

Air Quality Alerts (AQA)

Air Quality Indexes (AQI)

About the Air Quality Index

The EPA developed the Air Quality Index (AQI) which reports levels of ozone, particle pollution, and other common air pollutants on the same scale. An AQI reading of 101 corresponds to a level that is above the national air quality standard – the higher the AQI rating, the greater the health impact. The AQI is divided into color-coded categories, and each category is identified by a simple informative descriptor. The descriptors are intended to convey to the public information about how air quality within each category relates to public health. 

The table below defines the AQI categories.

AQI

AQI Category

AQI

Color Formulas

Numbers

(Descriptor)

Color

(RGB)

(CMYK)

0 – 50

Good

Green

0,228,0

224,0,224,30

51 – 100

Moderate

Yellow

255,255,0

0,0,255,0

101 – 150

Unhealthy for Sensitive Groups

Orange

255,126,0

0,132,255,0

151 – 200

Unhealthy

Red

255,0,0

0,255,255,0

201 – 300

Very Unhealthy

Purple

153,0,76

0,153,80,102

301 – 500

Hazardous

Maroon

76,0,38

0,76,38,179

in PA, NJ, DE, MD and the Delaware Valley

Partner Agencies for Air Quality

Air Quality Resources