Carl Zimmer

They can certainly go up maybe 12 miles.

Some expeditions, rocket missions have claimed to find them 40 miles in the air.

It's not clear, but you know,

we're talking 10, 20, 30 miles up is where all this life gets.

So this is, so people call this the arrow biome and we're living in it.

It's like we're in an ocean and we're breathing in that ocean.

And so you are breathing in some of those organisms literally with every breath.

Yes, I do have a CO2 monitor.

It's in the other room.

I take it with me partly to protect my own health, but also partly out of curiosity because carbon dioxide in the room is actually a pretty good way of figuring out how much ventilation there is in the room.

what your potential risk is of getting sick if someone is breathing out COVID or some other airborne disease.

They're not that expensive and they're not that big.

And taking them on planes is particularly illuminating.

It's just incredible just how high the carbon dioxide rate goes up.

You're sitting on the plane, they've closed the doors, you haven't taken off yet.

shoots way up.

Once you get in the air and the filter system starts up, it starts going down, which is good.

But then you land and back up again.

But in terms of, you know, when we're not flying, we're spending a lot of our time indoors.

And yeah, so you use the word commitment to indoor air quality standards.