It includes Frederick County.
...AIR QUALITY ALERT IS IN EFFECT FOR FRIDAY JULY 21 2017... The Metropolitan Washington Council of Governments in association with Maryland Department of the Environment, Virginia Department of Environmental Quality, and District Department of Environment has issued a Code ORANGE Air Quality Alert Friday for the DC metro area. A Code Orange Air Quality Alert means that air pollution concentrations within the region may become unhealthy for sensitive groups. Sensitive groups include children, people suffering from asthma, heart disease or other lung diseases and the elderly. The effects of air pollution can be minimized by avoiding strenuous activity or exercise outdoors. By The National Weather Service