N.C. Department of Environment and Natural Resources
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N.C. Air Awareness Program >> Air Quality Forecast Center >> AQI Color Code Guide

Air Quality Weather Conditions Recommended Actions Health Effects

Good

AQI: 0-50

(Green)

  • Cool summer temperatures
  • Windy conditions
  • Significant cloud cover
  • Heavy or steady precipitation
  • Keep cars and boats tuned up

  • Use environmentally safe paints and cleaning products

  • Conserve electricity-set A/C to highest comfortable level

No health effects are expected.

Moderate

AQI: 51-100

(Yellow)

  • Temperatures in the upper 70's to lower 80's
  • Light to moderate winds
  • Partly cloudy or mostly sunny skies
  • Chance of rain or afternoon thunderstorms

Unusually sensitive people should consider limiting prolonged outdoor exertion.

Unhealthy for Sensitive Groups

AQI: 101-150

(Orange)

  • Temperatures in the 80's and 90's
  • Light winds
  • Mostly sunny skies
  • Slight chance of afternoon thunderstorms
  • Limit daytime driving

  • Limit vehicle idling

  • Refuel vehicles after dusk

  • Don't "top off" your gas tank

  • Avoid congested periods

  • Use water-based paints

  • Use transit or car pool

  • Bike or walk for short trips

  • Use newest/best maintained car

  • Combine trips and share rides

  • Postpone using gasoline mowers

  • Barbecue without starter fluid

Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.

Unhealthy

AQI: 151-200

(Red)

  • Hot, hazy, and humid
  • Stagnant air
  • Sunny skies
  • Little chance of precipitation

Active children and adults, and people with respiratory disease such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion.

Very Unhealthy

AQI: 201-300

(Purple)

  • Hot and very hazy
  • Extremely stagnant air
  • Sunny skies
  • No precipitation

Active children and adults, and people with respiratory disease such as asthma, should avoid all outdoor exertion; everyone else, especially children, should avoid prolonged outdoor exertion.

AQI refers to the Air Quality Index.
An AQI of 100 is equivalent to the National Ambient Air Quality Standard (NAAQS).
An AQI greater than 100 is considered to be above the national standard or NAAQS.
An AQI Calculation Table is available online to convert raw ozone concentrations to the Air Quality Index.

*The weather conditions listed above are common weather types associated with the respective air quality levels.
A combination of part or of all these weather conditions could lead to a certain level of observed air quality.


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Last Modified: Wed June 24 10:12:07 2009
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