141–150 of 499 posts
Natural CO2 in a room probably correlates strongly with other things given off by humans... Farts, water vapour, viruses, etc.
The effect needs to be properly understood before totally redesigning the nations ventilation systems on a possibly wrong premise.
I 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…
Article author completely ignores this for the obvious reasons.
Can someone provide an explanation why CO2 concentrations above 1000 ppm have such a negative influence given the fact that CO2 concentration in lungs (at rest) never falls below 10000 ppm?
I'm not a doctor, but I would consider it in terms of flow and throughput , rather than,—metaphorically—the amount of water the pipe can hold.
I imagine it could easily be compensated by an equivalently minor increase of breathing rate or breathing depth.
[1] https://en.wikipedia.org/wiki/Gas_exchange#Alveolar_air
[2] https://en.wikipedia.org/wiki/Breathing#Composition
[3] 5/6 × 40000 ppm + 1/6 × 500 ppm = 33417 ppm; 5/6 × 40000 ppm + 1/6 × 5000 ppm = 34167 ppm; 34167 / 33417 = 1.0225
Earlier quoted context omitted.
ALSTUGA does not work with Zigbee. They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Some of the new devices (mostly those who support TouchLink, e.g. some of the lights) have a secret pairing mode with which you can use them with Zigbee, but it's only a subset of the new products.
> They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Uuh, seems not keeping up with social media finally backfired. That sounds horrible! So far IKEA been a great experience when it comes to HA+Zigbee stuff, and I started buying stuff relying on they'd keep just keeping up with that, really sad to hear they've changed course. The "secret pairing mode" stuff sounds the same as cu…
Earlier quoted context omitted.
I think the issue is that the common tech requires sensors in an air-chamber. E.g. NDIR works by firing IR at a frequency that is absorbed by CO2. A sensor on the other side either measures the amount of IR light that got through (optical NDIR) or pressure/sound waves (photoacoustic NDIR). I guess that it's hard to use any existing sensors, because they are relatively large and probably water could easily get into th…
Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.
Earlier quoted context omitted.
I think the issue is that the common tech requires sensors in an air-chamber. E.g. NDIR works by firing IR at a frequency that is absorbed by CO2. A sensor on the other side either measures the amount of IR light that got through (optical NDIR) or pressure/sound waves (photoacoustic NDIR). I guess that it's hard to use any existing sensors, because they are relatively large and probably water could easily get into th…
Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.
Earlier quoted context omitted.
ALSTUGA does not work with Zigbee. They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Some of the new devices (mostly those who support TouchLink, e.g. some of the lights) have a secret pairing mode with which you can use them with Zigbee, but it's only a subset of the new products.
> They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Uuh, seems not keeping up with social media finally backfired. That sounds horrible! So far IKEA been a great experience when it comes to HA+Zigbee stuff, and I started buying stuff relying on they'd keep just keeping up with that, really sad to hear they've changed course. The "secret pairing mode" stuff sounds the same as cu…
If you already own the ikea hub, they secretly put thread radio in it which was just sitting unused in preparation for this range.
For the DIYers, it's simple to get an SCD4x sensor and hook it to a pi, arduino, ESP32 etc (then use CC to create a live web interface). I did this after trying an Inkbird CO2 monitor, which gets reasonable scores in reviews and wanting a live web report in the office. Interestingly the Inkbird and the SCD4X quite often diverge by anything up to hundreds of PPMs; I kind of back the SCD4x (on a Pi in my case) for accu…
https://www.ikea.com/au/en/p/alpstuga-air-quality-sensor-sma...
Earlier quoted context omitted.
Oxygen sensors used in car catalyst systems use a different effect based on electrochemistry. I see no reason that couldn't be minuaritized to grain-of-sand size. The question is if oxygen levels are as good an indicator as CO2 levels... I suspect not.
I don’t think we actually care about co2 levels. I think we use them as a proxy for o2 levels (same as our bodies do). So your idea would be great.
https://science.nasa.gov/earth/explore/earth-indicators/carb...