Air Quality and Your Summer Vacation Outdoors

by Susan Stone

Air quality in the United States has improved considerably.  But, summertime air quality can still reach the unhealthy ranges of the Air Quality Index (AQI) – even in remote locations such as our beautiful national parks. Picture this: you’re camping in Great Smoky Mountains National Park (one of my favorites). You’re ready to take your kids hiking for the day, and you see a sign announcing a park-wide ozone advisory.


One of your teenagers has asthma. What can you do?

The first step is to check the daily AQI. I check the AQI forecast and current conditions before any hike by entering the zip code into the free AirNow app on my phone. In a national park, you can check with the park rangers if you don’t have the app.  Then use the AQI to help decide whether to change or restrict your activities — something that’s especially important if you’re in a group at greater risk from ozone exposure.

For example, when my children were younger, I didn’t take them on long hikes if ozone levels were Code Orange or above. Children, including teenagers, are considered to be at greater risk from ozone because their lungs are still developing. And children with asthma are at the greatest risk because ozone can cause or increase inflammation in airways.

Asthma is a disease characterized by airway inflammation. It’s this inflammation that can trigger an asthma attack, and it’s inflammation that your child’s asthma action plan is designed to prevent or limit. As ozone levels increase from Code Orange to Code Red on the AQI, it’s more important to limit prolonged, or strenuous, outdoor activities. Take more rest breaks and always pay attention to symptoms. This same approach ensures that kids can engage in outdoor activities safely at school, while still encouraging them to achieve the recommended 60 or more minutes of physical activity each day.

So, if today’s ozone AQI forecast in Great Smoky Mountains National Park is Code Red (unhealthy for everyone), the park ranger may recommend that your entire family avoid prolonged, intense activities today and engage in activities at the more sheltered, lower elevation areas of the park rather than the exposed ridgetops. You could plan your more strenuous hike for the next day, when the ozone forecast is Code Yellow. If you were planning to hike the Alum Cave Bluff Trail on the way to Mt. LeConte, a moderately strenuous trail that rises 2,900 feet to 6,400 feet, you could change your plans to visit Cades Cove, a broad valley that offers the widest variety of historic buildings in the park.


Walking around the historical sites in the valley would allow your family to continue enjoying your outdoor vacation, but keep activity levels low enough to avoid unhealthy air pollution exposures.

Check your daily AQI and download the free AirNow app:

About the author: Susan Stone is a Senior Environmental Health Scientist who likes to hike, especially in national parks and North Carolina state parks. Her most recent national parks visit was to Rocky Mountain National Park in Colorado. She checked the AQI as part of her hiking plans and had a great time.

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