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Air Quality Index

The AQI is an index for reporting daily air quality, developed by the EPA. It tells citizens how clean or polluted their air is, and what associated health concerns they should be aware of. The AQI focuses on health effects that can happen within a few hours or days after breathing polluted air. The purpose of the AQI is to help citizens understand what local air quality means to their health. To make the AQI as easy to understand as possible, EPA has divided the AQI scale into the different categories shown below.

Air quality is measured by a network of monitors that record the concentrations of the major pollutants at locations throughout the state. These raw measurements are then converted into AQI values using standard formulas developed by EPA (see AQI conversion tables). An AQI value is calculated for each of the individual pollutants in an area.

The AQI is based on ozone levels averaged over an eight-hour period and particle pollution levels averaged over a twenty-four hour period.

Find out how you can help!

Air Quality Index	Air Quality Descriptor	Ozone Health Effects	Particle Pollution Health Effects	Color Code
0-50	Good	No Health Notice - No health impacts expected in this range.	No Health Notice - No health impacts expected in this range.	GREEN
51-100	Moderate	Limited Health Notice - sensitive children and adults should consider limiting prolonged exertion outdoors.	Limited Health Notice - Sensitive people should consider reducing prolonged or heavy exertion.	YELLOW
101-150	Unhealthy for Sensitive Groups	Health Notice - Sensitive children and adults and people with heart or a respiratory disease, such as asthma, should limit prolonged exertion outdoors.	Health Notice - People with heart or lung disease, the elderly and children should reduce prolonged or heavy exertion.	ORANGE
151-200	Unhealthy	Health Advisory - Sensitive children and adults and people with heart or a respiratory disease, such as asthma, should limit exertion outdoors; everyone else, especially children, should limit prolonged exertion outdoors.	Health Advisory - People with heart or lung disease, the elderly and children should avoid prolonged or heavy exertion; everyone else should reduce prolonged or heavy exertion.	RED
201-300	Very Unhealthy	Health Alert - Sensitive children and adults and people with heart or a respiratory disease, such as asthma, should avoid exertion outdoors; everyone else, especially children, should limit exertion outdoors.	Health Alert - People with respiratory or heart disease, the elderly, and children should avoid any outdoor activity; everyone else should avoid prolonged exertion.	PURPLE
AQI Conversion Table (Ozone) | AQI Conversion Table (Particle Pollution)

How You Can Help

• Combine errands, reduce trips
• Conserve energy - at home, work, everywhere
• Use environmentally safe paints and cleaning products
• Conserve electricity and set air conditioners no lower than 78 degrees
• Choose a cleaner commute - share a ride or use public transportation
• Avoid using gasoline-powered lawn and garden equipment when unhealthy conditions are forecast
• Keep car, boat and other engines tuned up according to manufacturer specifications
• Reduce gas vapors by refueling cars and trucks after dusk
• Improve gas mileage by inflating tires to recommended pressure
• Limit idling

 

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