D.C. air quality improves

Good news: Air quality in D.C. is improving, according to year-over-year data.

By the numbers: The average percentage of fine particle pollution in D.C. decreased 5.2% from 2021-23, compared to 2014-16.

The big picture: Tracking fine particulate matter (PM2.5) is a helpful indicator of air pollution and a major factor in air quality index scores, but it doesn't account for all variables. So air pollution can be worse than it appears on your weather app.

• A growing body of research shows that polluted air is connected to poor reproductive outcomes, increased dementia risk, and more asthma attacks and other respiratory health effects.

To stay safe, air quality experts recommend checking your local AQI, and also trusting your nose. If you smell smoke — even if the AQI is "green" — limit your time outside.