Office buildings with recirculated air can get stuffy and stale.

有再循环通风系统的写字楼可能会空气不好。

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For sufficient ventilation and passenger comfort a common cold air manifold mixes the pack fresh air with recirculated air.

为达到充分的通风和旅客舒适度，使用一个通用的冷空气总管来掺混空调组件的新鲜空气和再循环空气。

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The recirculated air usually passes through high-efficiency particulate (HEPA) filters before delivery into the cabin.

CNN: Commentary: Flu and your health on a plane

To minimize the risk of disease spread by aircraft, regulations requiring HEPA filters for any aircraft that uses recirculated air should be seriously considered.

CNN: Commentary: Flu and your health on a plane

But he said there was no evidence air conditioning systems in buildings, or the recirculated air on planes, was involved in the spread of the disease.

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