Traveling with Apple Vision Pro

Not criticism, genuinely curious: why? I thought cabin air was exceptionally well cycled and filtered, much more so than other indoor spaces.

At the very least so one doesn’t sneeze over the person on the next seat.

I used to think this especially since airlines touted how good the air filtration was when COVID hit.

It's actually quite poor and significantly worse than most indoor spaces I've entered (most spaces aren't great at around 800-1600ppm). On planes I've measured※ very high CO2 levels (1800-4000ppm), with the worst air during boarding and deplaning. This matches the findings of others (both amateur and professional researchers).

※ - using Aranet4

Airplane air is clean but there are just too many people aboard and for too long. Something like a quarter of all air travel passengers get a respiratory illness within a week. Some hypothesize that the incredibly low humidity of cabin air (in most aircraft, except the very newest) makes it easier to acquire infections. A face mask, in addition to its normal role, also solves this problem because it is very humid inside the mask.

Are CO2 levels a useful way to measure filtration?

Are we expecting almost all the clean air to be from outside, minimal amounts from recirculation?

I don't know, but I always tended to get sick after flying. I started wearing a mask while flying during COVID and it's the one place I still do it. Not scientific but I feel like I have gotten sick after flying less frequently since then. It could even just be the effect of making myself breathe humid air in what's normally an extremely dry environment.

How does an N95 help with CO2 levels?

I would wager it's not a matter of helping filter out CO2, but rather CO2 is one way to assess how effective the air management is on a plane.

There are long periods where the filters aren't running during startup and shutdown, you'll notice once the seatbelt sign turns on at the beginning and right after it turns off at the end, things get stale super quickly and the temps start rising. That's because they turned off/haven't switched to air supplied by the jetway yet.

Apologies, I specified "filtration" but meant "quality", which I would define as filtration + fresh air intake.

I'd have expected a better mix (more fresh air) since even with filtration removing many particulates and viruses, high CO2 levels still cause worse cognitive performance.

It's hard to get lots of fresh air into a pressurized plane, so I'm willing to have a good bit of leeway on that front. And airflow patterns are important; a lot of fresh air running from front to back would likely do more harm than good.

A few family members caught covid on a plane despite everyone needing a negative covid test before departure and wearing a FFP2 mask during the whole flight.

Put a lot of people in close proximity for a long time and it's going to be very hard to prevent transmission of airborne viruses...

I love how the recent availability of cheap PPM and CO2 sensors spawned a whole new subculture of air quality paranoia.

Based on Veritasium's recent video, given the cabins are pressurized by bleeding air off of the jet engine might not be too surprising about CO2 or particulates. However the cabin air is also exceptionally dry.