Mamu My jeep has a recirculation button, but only on the coldest air-conditioning setting. The downside is that if the air inside your car is considerably warmer than outside then it will take longer to cool your interior. The rest area bathrooms and gas station bathrooms are not good for me - air fresheners, cleaning products, people smoking. You will miss your connecting flight. Mamu No smoking chambers.
People have to go outside to smoke.
Mamu I traveled a lot when I was working. I got to the point where I refused to run in air terminals. I'd rather miss the flight. You can always arrange another. So decrease the amount of caffeine you normally consume on days you are going to fly.