Clean air is easier to breathe, especially if you have chronic obstructive pulmonary disease (COPD). Poor-quality air can cause symptoms such as coughing and shortness of breath. It can lead to needing more medicines or even send you to the hospital. Fortunately, the air quality index (AQI) tells you what the air is like outside. The EPA calculates the AQI for five major pollutants: particle pollution (often referred to as particulate matter), ground-level ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide. For each of these pollutants, EPA has established national air quality standards to protect public health. Of the five pollutants, particle pollution and ground-level ozone can make COPD worse.
Air quality constantly changes. The AQI uses a scale from 0 to 500 to track those changes. The higher the AQI value, the greater the level of air pollution. Here's what the numbers on the scale mean:
Below 100: The air is safe for outdoor activity for most people.
101 to 150: The air is unhealthy for sensitive groups, such as people with lung or heart disease.
151 to 200: The air is unhealthy for all groups.
201–300: The air is very unhealthy.
301 to 500: The air is hazardous.
An AQI above 150 means that you should avoid any outside exertion.
You can find the current AQI in several ways:
AQI forecasts are on the same newspaper page as your local weather.
Broadcast meteorologists warn when the AQI is going to be high.
The EPA's website shows the current AQI where you live. The AIRNow website offers daily air quality forecasts for ozone pollution as well as real-time air quality conditions for over 300 cities across the U.S.