Wonder how to measure Colorado Air Quality? AQI Explained

Air pollution is of great concern, and the Air Quality Index (AQI) is a helpful tool that tells you how clean or polluted your air is, and what associated health effects might be a concern for you. The Environmental Protection Agency (EPA) created the AQI, which provides information on five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution (also known as particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. A health-based National Ambient Air Quality Standard – the level EPA has set to protect public health - exists for each of these pollutants. Ground-level ozone and airborne particles are the two pollutants that pose the greatest threat to human health in the United States.

The AQI is an easily understood 0-to-500 scale. The higher the number, the greater the level of air pollution and the subsequent health concern. An AQI value of 100 generally corresponds to the National Ambient Air Quality Standard set for that pollutant. To make it even simpler, there are colors assigned to each of the six categories of the AQI.

• Green, 0-50, GOOD. Air quality is considered satisfactory, and air pollution poses little or no risk.
•  Yellow, 51-100, MODERATE. Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people. For example, people who are unusually sensitive to ozone may experience respiratory symptoms.
• Orange, 101-150, UNHEALTHY FOR SENSITIVE GROUPS. Although general public is not likely to be affected at this AQI range, people with lung disease, older adults and children are at a greater risk from exposure to ozone, whereas persons with heart and lung disease, older adults and children are at greater risk from the presence of particles in the air.
• Red, 151-200, UNHEALTHY. Everyone may begin to experience some adverse health effects, and members of the sensitive groups may experience more serious effects.
• Purple, 201-300, VERY UNHEALTHY. This would trigger a health alert signifying that everyone may experience more serious health effects.
• Maroon, 301-500, HAZARDOUS. This would trigger a health warning of emergency conditions. The entire population is more likely to be affected.

Understanding local air quality is an important part of staying healthy. If you suffer from a pre-existing respiratory condition like asthma or are otherwise sensitive to air pollution, it would benefit you to stay informed about current air pollution conditions. The AQI is a helpful tool that enables anyone to ascertain at a glance whether the conditions are favorable to their health. Visit the state of Colorado’s website at http://www.colorado.gov/airquality or the EPA’s Air Quality Index information page at http://www.airnow.gov/index.cfm?action=aqibasics.aqi for more information.