According to the Metropolitan Washington Council of Governments’ Ozone Season Summary, the region recorded just two days of unhealthy ‘Code Orange’ air quality in 2020 due to ground-level ozone and zero days of more serious ‘Code Red’ air quality. Last year, the region recorded 10 Code Orange days. In 2010, when measured against the current ozone standard, the region experienced 48 unhealthy air days. The region has also gone four out of the last five years without a Code Red day for ozone pollution.

These positive trends are the result of more than a decade of action and coordination at the federal, state, and local government levels, such as regulations to reduce emissions from power plants, passenger vehicles, and heavy-duty diesel engines as well as programs to improve energy efficiency and renewable energy use.

COG experts also attribute this year’s low ozone pollution levels to COVID-19 related restrictions, such as the stay-at-home orders across the region, which led to a reduction in emissions due to lower traffic and fuel and electricity consumption. In addition, the weather—a cooler, drier May and a wetter than average July and August—contributed to the improved air quality.

While this year’s air quality demonstrated continued and significant improvement, the region still does not comply with federal ozone standards, which are based on a three-year average, and officials remain focused on this longstanding priority.

Ground-level ozone is a colorless gas created when air pollutants react on hot, sunny summer days. Sensitive groups such as people with lung disease (including asthma, emphysema, and chronic bronchitis), children and older adults, and people who are active outdoors may experience adverse health effects when air pollution levels are elevated for a prolonged period of time.

The Metropolitan Washington Air Quality Committee, which is staffed by COG, coordinates air quality planning in the region. Its members include area elected officials, environmental directors, and state air management and transportation officials. COG provides air quality forecasts for metropolitan Washington. It also educates the public about voluntary actions people can take to reduce pollution and the health risks of bad air quality through its Clean Air Partners program, which is co-sponsored by the Baltimore Metropolitan Council.

MORE: Air Quality Progress Dashboard