Hacker News Reader

Comment by kashishgrover | Hacker News Reader

Oh this is absolutely so relevant and I wonder if there are any high quality studies that have analyzed driving performance against CO2 buildup in cars. Cars often ship with circulate air feature in the aircon, and people use it aggressively, nonchalantly at least where I live, having no idea about the dangers of possible hypoxia and sleepiness that might be inducing in them while driving. It is absolutely critical in my opinion for cars to have CO2 monitors. We put so many sensors in cars these days that this seems to be a really cheap and fairly high value of life addition that could possibly prevent accidents on roads. I keep a portable CO2 sensor in my car at all times, because sometimes circulation is not something I can avoid when stuck in traffic or when passing by a drain.

View on HN

Got a firsthand experience with this. I was dropping off my girlfriend and we stopped to talk in the car, with all the windows up. Over the course of the conversation we got more and more agitated at each other until I had a thought and pulled my Aranet out from my backpack. It was >3000ppm CO2. We opened windows and within 2 minutes all the agitation went away.

To be fair, that might not just have been the CO2 dropping, but also the pattern interrupt + giving you both an easy and face-saving way out of that situation.

Or, you became aware of the agitation and interrupted it. The CO2 was a placebo. You have invested already in the idea, it all clicked in your mind.

I'm not sure this is a helpful comment. This is a common story with many medications, where someone notices their feelings are off and suddenly remembers that there is a probable root cause. It's why medications list side effects.

I was amazed how quickly it rises in the car with windows up and recirculate mode for the fan. There's a reason it has a fresh air mode.

Your comment actually has me convinced that this isn't an issue. I've been a recirculation dude for my entire life, I literally don't drive any other way.

In the 1970's when factory A/C started to get widespread adoption in other than very expensive cars, it was common for more than one US automaker to almost standardize on a dashboard system of levers or knobs.

At the extreme was "MAX" which most people didn't realize was "recirculate" unless they read the owner's manual in those cases where it was well documented. The next notch over was "NORM" which as the name implied was intended to be the "normal" setting except under more challenging conditions. But with fresh air coming in constantly it only was passing through the refrigerant coils one time, plus sometimes the outdoor air is a lot hotter than others, so recirc is when you want the same interior air to pass through the coils more than once.

All this may go "out the window" when the exhaust fumes or worse in the outdoor air need to be excluded as much as possible.

I kind of miss the old '70's cars even though loads of them kept running long after the A/C had failed.

Regardless, I never felt alone even without a passenger, with my good buddies Max & Norm with me everywhere I went ;)

Relevant video of someone experimenting with a CO2 monitor in a car: https://youtu.be/hr9w-ZixAqc

Buildup of CO2 and reduction in O2 are two different effects. We're not in danger of running out of O2 in any everyday situation.

Cars are not sufficiently sealed for that to make any kind of a difference.

Try it yourself. They really are

I've had quite a lot of makes and models of cars apart to a bare shell.

They're just not that sealed up.

Cars aren't hermetically sealed vessel. This is hilarious.

You think that’s stopping CO2 buildup?

Lol yes

I laugh pretty easily myself :)

Of course some things are more hilarious than others :)

>Cars aren't hermetically sealed

I can agree with that completely.

Not my downvote btw, corrective upvote instead :)

Naturally I often wonder if many people know what Hermetically sealed is all about to begin with.

I do a bit of that in the lab when I seal flammable reference materials inside glass ampules using a torch. But it's not the sealing that counts, it's the technique ;)

If you check Wikipedia, you may notice that the terminology is older than the internet in every way.

Specifically they do not show awareness that it really means "sealed in such a way that it can't be figured out. As if by God. Not just any God but the ancient Roman God Mercury, otherwise known as Hermes when worshipped by the ancient Greeks."

Now I can only assume you have never been in a new 1960's WV beetle when all windows and the manual vents were shut (they didn't have A/C) when somebody slammed the door. You eardrums would remember it if so.

Cars are leaky as fuck. They are more leaky than your house. There is 0 potential of CO2 buildup that is anything remotely close to being harmful.

Yeah, I measured over 5000ppm in a taxi with two passengers. Showed the driver how to enable air intake (he didn’t know about the feature) and tried to explain this is deadly. Pretty sure this is commonplace globally.

Generally it’s a miracle to me so many people survive traffic on public roads, statistically.

Reply on news.ycombinator.com