On a typical passenger jet, the ratio of fresh to recycled air is about 50-50.

More of our recycled air was coming from the algae tanks now.

Boeing and airline industry officials insist that the recycled air presents no problems.

Actually, the recycled air on planes is probably better for you than most air in office buildings.

He threw back his arms and breathed the recycled air.

There was no wind in the dome, of course, and the recycled air got stale real fast.

It was in an underground bunker, with no windows and only recycled air to breathe.

The wind is generated above the room then brought down through vents and fans using recycled air.

For one thing, he only had to smell his own recycled air.

You breathe recycled air, and get the courthouse cold, flu or headache.