You know what also impacts my decision making ability? Freezing my ass off because people are opening all the windows every five minutes.
The bottleneck might be the air in the room
211–220 of 499 posts
Re: The bottleneck might be the air in the room
#212Earlier quoted context omitted.
CO2 and all other air quality indexers have to be very carefully calibrated regularly. It's not some slop you can just throw into a consoomer cheap iot device. Article author completely ignores this for the obvious reasons.
For the purposes of indoor ventilation monitoring you can calibrate by occasionally exposing the sensor to fresh air. Either taking it outside or just the room not having people in it. The sensor will treat the lowest reading it gets as 400ppm since this is what outdoor air is. A sensor mounted in the office will get calibrated every night when the office is empty.
The outdoor CO2 is rising every year. It is not fixed at 400 ppm. The calibrations you speak of are fake. A good sensor can be expected to remain within 10% of reference for ten years.
Re: The bottleneck might be the air in the room
#213Earlier quoted context omitted.
> Thread is significantly better. Better than what already exists and is deployed? I dunnno, hardware already in use always beat "hardware conceptually better but I don't have it", that's why Zigbee is better, for me . Protocols much like everything in the world, isn't correct/incorrect or universally "better", it's all down to use cases. Personally, as someone who started to rely on IKEA providing Zigbee devices, Th…
Ikea preemptively sorted this out by putting thread radio in their hubs years before rolling this out. There's also thread radios in the latest chromecast, apple tv, and loads of other products. If you have a single thread border router in your house from any brand you'll be able to connect to any thread device from any brand. Phones can also directly control thread devices without needing any network or hub. It's a…
smart home companies have been deploying the thread hardware for years before anyone started using it
Also worth mentioning that many modern Zigbee radios can also be Thread thread radios using different firmware. There are even multi-PAN radios that can do Zigbee and Thread at the same time. Some smarthome hubs use multi-PAN (e.g. Homey Pro), but it's generally recommended against now because of lower reliability.
The same applies to devices, e.g. some of the new IKEA devices work over Thread or Zigbee (Zigbee pairing is triggered using a non-documented sequence, presumably they added support for TouchLink). Or e.g. the Aqara FP300, which can be flashed with Thread + Matter or Zigbee firmware. It works because the same radio can be used for both protocols.
Re: The bottleneck might be the air in the room
#214I really wish a Apple or another major OEM would integrate CO2 monitor into watches or smartphones. Suddenly, everybody would be aware of the CO2 level in the room, get alerts, etc. and the problem will just solve itself. There are so many rooms, classrooms, movie theaters and other places with poor ventilation where you just feel dizzy, or fall asleep, not knowing it was just due to lower oxygen levels in your blood…
CO2 and all other air quality indexers have to be very carefully calibrated regularly. It's not some slop you can just throw into a consoomer cheap iot device. Article author completely ignores this for the obvious reasons.
Not really. For ventilation purposes, a good sensor remain within 10% variation for nearly ten years. We are not running a controlled science experiment here.
Re: The bottleneck might be the air in the room
#215As a high school teacher, I first noticed this effect when I started using a CO2 monitor in my classroom as a proxy for air freshness during COVID. The CO2 levels in our supposedly "no problem with the air" classrooms shot up to 2000 ppm within minutes of the start of school and stayed there all day. Kids weren't checked out ONLY because I teach mathematics. They were breathing bad air, too. Worse, when I brought the…
Your comment is suspiciously missing the part where your students performed measurably better after decreasing CO2 concentration.
Re: The bottleneck might be the air in the room
#216Earlier quoted context omitted.
I notice that thinking becomes less clear when going above 1000ppm, so I let HA send a notification at 1000ppm. With ALPSTUGA it would send already at 700ppm. By the way, above 1000 the divergences become even larger due to the inaccuracy also being 10% of the ambient CO2 concentration (in optimal circumstances, probably larger IRL). So, suppose you want to be notified at 2000 ppm, the IKEA sensor might already do so…
Can you recommend some?
Mentioned two here: https://news.ycombinator.com/item?id=48783879
Re: The bottleneck might be the air in the room
#217I really wish a Apple or another major OEM would integrate CO2 monitor into watches or smartphones. Suddenly, everybody would be aware of the CO2 level in the room, get alerts, etc. and the problem will just solve itself. There are so many rooms, classrooms, movie theaters and other places with poor ventilation where you just feel dizzy, or fall asleep, not knowing it was just due to lower oxygen levels in your blood…
> There are so many rooms, classrooms, movie theaters and other places with poor ventilation where you just feel dizzy, or fall asleep, not knowing it was just due to lower oxygen levels in your blood. Raising awareness is the only real solution.
Not wrong, but it is perhaps worth noting that there are already standards for proper ventilation. Generally you're looking at 5–10 cfm/person (2.5-5 L/s), depending on the facility and purpose of the room; see Table 6.2.2.1 in ASHRAE Standard 62.1 for the US:
* https://www.ashrae.org/file%20library/technical%20resources/...
Maybe set up a monitor, but if the room/facility has recently been renovated and meets modern (>2013) building codes, this 'should' have already been taken into account.
Re: The bottleneck might be the air in the room
#218As a high school teacher, I first noticed this effect when I started using a CO2 monitor in my classroom as a proxy for air freshness during COVID. The CO2 levels in our supposedly "no problem with the air" classrooms shot up to 2000 ppm within minutes of the start of school and stayed there all day. Kids weren't checked out ONLY because I teach mathematics. They were breathing bad air, too. Worse, when I brought the…
>The good news is that I stopped worrying about making my house "tight" for the sake of energy efficiency. I keep some windows cracked all year and don't worry about how tight the door seals are.
You could also install an energy recovery ventilation (ERV) system.
Re: The bottleneck might be the air in the room
#219I’m not saying this isn’t a legitimate concern but this really seems to have exploded amongst the tech community as the next obsession. I see this pop up on X every few weeks. Is the concern about this really based on actual science? Is there empirical data proving people are less productive or are damaging themselves as a result of heightened CO2 levels? And I don’t mean observational epidemiology studies.
I’ve lived in Australia and France and I’ve always attributed the taller size of Australians to the excellent state of their ventilation in buildings. Vents (and rooms themselves) are systematically bigger than in France, and if you live in a healthy environment, with meat, lots out outdoors during teen age, and correctly ventilated classrooms during their 20 best years, it makes no secret to me that they grew bigger…
So how does any of that relate to height? From what data I could quickly find, both countries are essentially equal in average height.
Re: The bottleneck might be the air in the room
#220I have a CO2 monitor and I don't understand one thing - it seems that CO2 increases more quickly during summer than during winter. If I close my windows it takes longer to reach 1000 ppm during winter than it does during the summer. I didn't gather concrete data on this but this is just what I eyeballed over the last few years. Does anyone know why could this be the case?
Do you have a forced-air heating system?