That includes New York, where there is an air quality alert and heat advisory out through the weekend because of heat indices that probably will hover just below or surpass 100.

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Cilluffo said, though, that more needs to be done to make sure the threat alert for air security matches up with national security.

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According to Israel's army radio, army chief Lieutenant General Gaby Ashkenazi had ordered ground, air and naval forces to be on alert.

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Citizens of metro Atlanta experienced their first "code red smog alert" since 2010, according to the Clean Air Campaign, a partnership between employers and the state transportation department.

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When operating properly, the monitors constantly sample the air and send data to EPA headquarters, where computers monitor the data and alert officials to unusual readings.

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