For nearly 20 years, Maryland's air quality has improved. Maryland is in compliance with federal air quality standards for four of the six criteria pollutants: carbon monoxide, lead, nitrogen dioxide, and particulate matter. Maryland is continuing efforts to comply with the federal standards for ozone and sulfur dioxide.
Clean air matters to Maryland, our neighboring states and the Chesapeake Bay, and that is why we are committed to a course of air quality improvements. The 2020 Report is avaliable here.