What does the AQI mean? The scale goes from 0 to 500. 0 is good and 500 is the most hazardous air quality.

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According to the United States Environmental Protection Agency (EPA), air pollution can be dangerous to everyone at very high levels. It can be dangerous for people with lung conditions like asthma or COPD at lower levels. The daily AQI measures air pollution from ozone, particle matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.

What Does Air Quality Mean and What Is Unhealthy Air Quality?

Every day, the EPA issues AQI numbers for areas all around the country. This number tells you if your air quality is good, moderate, unhealthy, or bad. AQI numbers start at 0 and can go up to 500. The higher the number, the worse the air pollution. AQI numbers rarely go above 200 in the United States. These are the numbers and what they mean:

• AQI of 0 to 50 is good air quality, and safe for everyone. The color code on an AQI chart is green.
• AQI of 51 to 100 is moderate air quality. AQI of 100 is the limit of air quality considered to be satisfactory for most people. People who are very sensitive to air pollution may have symptoms from this level of pollution. The color code is yellow.
• AQI of 101 to 150 is unhealthy air quality for sensitive groups, such as people with asthma or other lung conditions. People without these conditions usually do not have symptoms. The color code is orange.
• AQI of 151 to 200 is very unhealthy for sensitive people. They may experience severe respiratory symptoms. People without lung problems may also experience symptoms. The color code is red.
• AQI of 201 to 300 is very unhealthy for everyone and a health alert is issued. The color code is purple.
• AQI over 301 is hazardous for everyone and a health warning emergency is issued. The color code is maroon.

Respiratory Symptoms From Unhealthy Air Quality

These symptoms can include cough, throat irritation, shortness of breath, chest tightness, wheezing, or chest pain or burning. It may be painful to take deep breaths. Lung conditions like COPD or asthma may suddenly get worse. Hospital admission for respiratory disease typically goes up during a time of poor air quality. People who are at risk of respiratory issues during a period of poor air quality include children and adults with asthma, people over age 65, and people with long-term health conditions like diabetes and heart disease.

What to Do When Air Quality Is Unsafe for You

If you or someone in your family is at risk from air pollution, you should check the daily AQI numbers in your area. You can find your AQI numbers in your local newspaper or on your local news station. National media companies like CNN, The Weather Channel, and USA Today publish AQI numbers and warnings for all areas of the country. You can also find your AQI at the EIP website airnow.gov.

If your state or local environmental protection department participates in a program called EnviroFlash, you can receive air pollution alerts or warnings. These warnings are especially important for unexpected air pollution from fires.

If the air quality is unsafe for you:

• Limit outdoor air exposure.
• If you need to be outside, avoid times of higher high air pollution, late afternoon and evening.
• Stay away from highway traffic areas.
• Avoid moderate exertion outdoors, which includes activities like brisk walking, light jogging, physical work, and or running sports.

Indoor air pollution could come from the poor quality air outside, so make sure to stay on top of replacing air filters around the home.

Do Air Purifiers Work for Air Pollution?

AQI only measures outdoor air pollution. If you are at risk from poor air quality, the EPA recommends an indoor air purifier. Indoor air pollution may come from outdoor air it may come from indoor air pollution sources like cooking, cleaning, or secondhand smoke. The EPA says that using a portable air purifier or upgrading the air filter in your furnace, central heating, or air-conditioning system can help to improve indoor air quality.