What is the Air Quality Index? Is it Safe or Unsafe to Breathe?


From wildfires to car exhaust, there’s a lot that affects the quality of the air we breathe. Wondering if it’s a good day to go out and play? The EPA’s Air Quality Index has your whole family covered.

By Elaine Cudnik, A.P.R.N., Renown Pediatrics

Humans have and always will depend on air for survival. But the quality of the air we breathe has declined over the years.

According to the Environmental Protection Agency (EPA), we breathe in more than 3,000 gallons of air each day. And at any given moment that air is littered with hundreds of pollutants. Generally we can’t see the toxins we breathe, but large concentrations of pollutants can be visible, like a cloud of smog hovering over a city or the smoke from a wildfire.

The EPA qualifies six major air pollutants as part of the Clean Air Act: ozone, particulate matter, carbon monoxide, nitrogen oxide, sulfur dioxide and lead. Natural sources can contribute to the presence of some of these pollutants: Wildfires and volcanic activity, for example, emit particulate matter and gases that impact our air quality.

But the majority of pollutants are introduced by humans — everything from car exhaust to power plants to farm equipment and even dry cleaners release toxins into the air.

Fortunately there’s an easy way to know when the air is safe or unsafe — the Air Quality Index (AQI). The easiest way to access AQI information is online at www.airnow.gov. It’s assessed according to AQI values, the associated level of health concern and a color that represents each level. So when should you worry about heading outside?

Understanding the Air Quality Index

Source: EPA

In general, when the AQI is green/good, there is no concern. Everyone should be able to participate in outdoor activities without restriction. When the AQI is yellow/moderate, most people are still OK, but those with severe respiratory illness or who are sensitive to ozone or particle pollution should limit outdoor time. When the AQI hits level orange/unhealthy, sensitive groups — such as those with conditions like asthma — should stay indoors. The general population, however, is unlikely to suffer any adverse effects.

Once the level is red/unhealthy or above, all persons may experience adverse health effects and should limit their time outside as much as possible.

The negative effects of poor air quality include decreased lung function with increased respiratory symptoms such as cough and runny nose. According to the EPA, certain toxins — such as benzene or vinyl chloride — can increase risk of birth defects, cancer, long-term lung damage, and nerve and brain damage. In extreme cases breathing these chemicals can result in death. And because air pollutants have reduced the ozone layer that protects us from the sun’s harmful rays, cases of skin cancer and cataracts have also increased.

As Nevadans, we all know to be mindful as summer and fire season approach. During these times, expect rapidly changing conditions in the AQI, and check air quality throughout the day. Limit outdoor exposure when air quality is poor if you or your loved ones are in a high risk or sensitive group. This includes children, the elderly, and those who are active or work outdoors. People with lung disease, such as asthma, are at the greatest risk.

Increased Risk for Children

Children are at higher risk because they play outside more frequently, have a faster respiratory rate and breathe in more pollutants, and have developing lungs that are more sensitive to pollutants. If your child is coughing more, breathing harder or presents cold-like symptoms on a high AQI day, they may be more sensitive to pollutants.

Air quality is generally better earlier in the day. So if you do have to be out and about when the AQI is red or above, get things done in the morning. Otherwise, settle inside with the windows closed and turn on the air conditioning. Be creative, and think of indoor activities to keep the kids occupied, entertained — and breathing clean air.

This story was also published in the Reno Gazette-Journal’s Health Source on March 27, 2016.