An Orange Air Quality Alert means there are unhealthy pollution levels for sensitive groups.
The Pennsylvania Department of Environmental Protection issued the Code Orange for ground-level ozone until midnight Monday. Those areas include Berks, Bucks, Chester, Delaware, Lehigh, Montgomery, Northampton and Philadelphia counties.
The New Jersey Department of Environmental Protection also issued a Code Orange until 11 p.m. on Monday. Those areas include Bergen, Burlington, Camden, Cumberland, Essex, Gloucester, Hudson, Hunterdon, Middlesex, Mercer, Monmouth, Morris, Ocean, Passaic, Salem, Somerset, Sussex, Union, and Warren counties.
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Parts of Maryland, New York and Connecticut are also under the alert.
An Air Quality Action Day is declared when the AQI is forecasted to be Code Orange or higher.
On an Air Quality Action Day, young children, the elderly, and those with respiratory problems, such as asthma, emphysema, and bronchitis, are especially vulnerable to the effects of air pollution and should limit outdoor activities.
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