By Alana Mauger

You have probably noticed air quality alerts popping up more frequently on your Red Cross Emergency app. Those alerts are a sure sign that ozone season is here. In the Greater Philadelphia area, episodes of elevated pollution are becoming more common in early spring, offering a preview of the conditions that typically intensify from May through September. 

During spring and summer, warmer temperatures and sunlight create the perfect conditions for ground-level ozone, which is a key ingredient in smog. During this time, communities are more likely to experience Air Quality Action Days, when pollution reaches levels that can impact public health. 

As the climate crisis continues to intensify extreme heat and wildfire impacts, ozone season is no longer just about awareness—it’s about being prepared and protecting yourself and your community.

Ozone Season

Early May kicks signals the beginning of ozone season, when hot weather bakes pollution from vehicles and other sources into harmful ozone in the air. This invisible pollutant damages lung tissue, makes it harder to breathe, increases susceptibility to respiratory infections and poses heightened risks for children, older adults and people with chronic conditions.

In recent years, communities across Pennsylvania have also experienced particle pollution from wildfire smoke, sometimes traveling hundreds of miles and creating hazardous air conditions with little warning. 

The Climate Connection

The climate crisis is making air quality challenges more frequent and severe: 

• Hotter, longer summers increase ozone formation; 
• Drier conditions fuel larger wildfires, spreading smoke across regions; and 
• Changing weather patterns can trap pollution closer to the ground. 

What used to be occasional poor air quality days are becoming longer and more common episodes, affecting both urban and rural communities. Poor air quality can worsen existing health conditions, disrupt daily life and compound other climate-driven disasters like extreme heat—placing additional strain on families and local systems. 

Information is Power

Locally, the Delaware Valley Regional Planning Commission (DVRPC) administers an Air Quality Partnership (AQP), which provides a real-time air quality index, issues air quality advisories and educates the public about air quality issues. AQP’s website also provides clean driving tips and lots of educational materials for children and adults.

For those outside of the Philly area, the U.S. Environmental Protection Agency (EPA) provides current air quality conditions by zip code via its AirNow website..

Protect Your Health

During ozone season , small actions can make a big difference in reducing your exposure and protecting your health.

• Limit outdoor activity — On poor air quality days, reduce time outside, especially strenuous activity, and plan outings for morning or evening when pollution is lower.
• Keep indoor air clean — Close windows and run air conditioning on recirculate to keep polluted air out.
• Use a HEPA purifier — A HEPA air purifier can help reduce smoke and fine particles indoors, especially in rooms you use most.
• Wear a high-quality mask — If you must be outside during smoky or high-pollution conditions, wear a well-fitting N95 or KN95 mask.
• Cut back on your personal pollution — Combine trips, avoid idling, and limit use of gas-powered equipment to help prevent air quality from worsening.

This ozone season, stay informed by bookmarking and consulting trusted resources, like AirNow and AQP. Share alerts with others and check in on vulnerable neighbors to help keep your community safe. Simple steps—like combining trips and limiting idling—can reduce pollution, while supporting broader climate and health efforts helps address long-term air quality challenges.