There were crying babies, screaming customers, non-circulating air and way too much stress.

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Once emitted, it persists in the environment for a long time - circulating through air, water, soil and living organisms - and can be dispersed over vast distances.

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The wind gains strength from the thermal energy of the ocean, eventually condensing vapors and circulating air fast enough to form high-speed wind and heavy rain.

CNN: graphic

Air circulation patterns aboard standard commercial aircraft are side-to-side (laminar), with air entering the cabin from overhead, circulating across the aircraft and exiting the cabin near the floor.

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One well-known study in 1979 found that when a plane sat three hours with its engines off and no air circulating, 72% of the 54 people on board got sick within two days.

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