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Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

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Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#81

Post by WilliamEdward »

SketchySeaBeast wrote: post #75
jakobegger wrote: post #68

Earlier quoted context omitted.

How much CO2 does a plant really turn into O2? I can't imagine that a few plants make much of a difference, or do they?

At night plants start to produce CO2 as well - when you're sleeping and most vulnerable! If the amount of CO2 they scrub is significant, the amount of CO2 they produce in the evening should be as well, no?

Plants produce a net deficit of CO2, so you're correct but over a 24 hour period with proper lighting they will produce more oxygen than CO2. The important thing, however, is that they produce this CO2 at night at such an unbelievably slow rate that you wont be choking to death in your sleep, that's silly. If you fill a room with plants and cut out the lights, most CO2 produced will be from your cat sleeping on the floor than from the plants.

Either way I was referring to other chemicals that plants remove from the air, not CO2.

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#82

Post by TremendousJudge »

thinkcontext wrote: post #76
drankula3 wrote: post #65

Earlier quoted context omitted.

My wife is a respiratory therapist. When asked, she said higher-than-average CO2 is seen in COPD patients, and is compensated through an increase in metabolic bicarbonate production, countering the acidic properties of CO2. We are still entering unknown territories with such large populations getting exposed to higher CO2 levels, but she thinks we'll be fine.

I'm having trouble recounciling that with the study that shows cognitive decline, can you explain your wife's thinking?

Maybe it means that if you are _always_ exposed to high CO2 your body adjusts, but if you are sporadically exposed it does not? Kind of like living in the mountains vs going there occasionally

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#83

Post by SketchySeaBeast »

WilliamEdward wrote: post #81
SketchySeaBeast wrote: post #75

Earlier quoted context omitted.

At night plants start to produce CO2 as well - when you're sleeping and most vulnerable! If the amount of CO2 they scrub is significant, the amount of CO2 they produce in the evening should be as well, no?

Plants produce a net deficit of CO2, so you're correct but over a 24 hour period with proper lighting they will produce more oxygen than CO2. The important thing, however, is that they produce this CO2 at night at such an unbelievably slow rate that you wont be choking to death in your sleep, that's silly. If you fill a room with plants and cut out the lights, most CO2 produced will be from your cat sleeping on the f…

Apparently plants put out half the CO2 again over the night that they took in. I'm just thinking that either way they aren't that big of deal as far as oxygen/carbon dioxide production/consumption. Air filtration, possibly.

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#84

Post by AYBABTME »

gsich wrote: post #74
Waterluvian wrote: post #51

I'm looking around for an affordable household CO2 measurement tool but they're all wildly expensive. Is this technology complicated and cannot be obtained for $30? They're all like $120+ Edit: I realised that this is a perfect item for public libraries to loan out. Expensive, only needed occasionally, easy to use, potential for significant positive public impact on becoming more informed and healthier. If you're loo…

MH-Z14 or Z19. But this is just the sensor, you'll need an Arduino/ESP/Rpi too.

What's particular about these sensors? I've been researching technologies to monitor plant growth and haven't yet looked into CO2 sensors, hence my asking. Do they come in an IC package?

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#85

Post by drankula3 »

TremendousJudge wrote: post #82
thinkcontext wrote: post #76

Earlier quoted context omitted.

I'm having trouble recounciling that with the study that shows cognitive decline, can you explain your wife's thinking?

Maybe it means that if you are _always_ exposed to high CO2 your body adjusts, but if you are sporadically exposed it does not? Kind of like living in the mountains vs going there occasionally

Exactly. Metabolic changes take time.

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#86

Post by stackmad »

WilliamEdward wrote: post #54
stackmad wrote: post #21

Earlier quoted context omitted.

You can only put link + title on here. And the story is rather boring :) I wanted to measure it, I got a device from amazon, found a python script to read the data, the dependencies (pyhidapi) always sigfaulted, so I wrote my own :)

Why do you need a script for this? Isn't the device good enough at telling you the bare necessary information? Still a cool script nonetheless, no hate.

Sure, but I wanted to see the data over time. And I was bored :)

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#87

Post by PascLeRasc »

michaelbuckbee wrote: post #67
fulafel wrote: post #59

Earlier quoted context omitted.

Slight aside, anyone know why all the supposedly iot-oriented small arduino devices are IPv4-only? Is everyone deploying them in some kind of NATs + port forwards / upnp system or tunneled overlay IPv4 network using external gateway devices?

Genuine question: are Arduino's really for IOT or for prototyping? Not an expert, just read a lot about startups starting with a RaspPI or Arduino prototype for the Kickstarter or something and then getting "real" dedicated hardware for production.

It is common to start with these before the Kickstarter, just to get a proof of concept, but those boards (and the ESP8266) absolutely aren't for production. Raspberry Pis are terrible since the only way to interface with them is over a single USB 2.0 port - and that's shared with the 100M ethernet and the SD slot.

You might see an ATMega328p chip isolated, and that's "good enough" for hobbyist projects where you just want to make HID easier on yourself. But I think most shops that need one of these three would be much better off with a STM32-series chip - they cost pennies compared to consumer boards, run on microamps, and have much better documentation.

It'd be a huge red flag for me if I was interviewing with a hardware startup and they said they wanted to put Arduinos into mass production.

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#89

Post by gsich »

AYBABTME wrote: post #84
gsich wrote: post #74

Earlier quoted context omitted.

MH-Z14 or Z19. But this is just the sensor, you'll need an Arduino/ESP/Rpi too.

What's particular about these sensors? I've been researching technologies to monitor plant growth and haven't yet looked into CO2 sensors, hence my asking. Do they come in an IC package?

They use optical measurement, are reasonable in pricing. Outputs are UART, PWM and analoge.

They have pins with 2.54mm spacing if that helps you.

Re: Show HN: I wanted to measure CO2 in my office, so I build a C++ WebServer/App

#90

Post by [deleted] »

PascLeRasc wrote: post #87
michaelbuckbee wrote: post #67

Earlier quoted context omitted.

Genuine question: are Arduino's really for IOT or for prototyping? Not an expert, just read a lot about startups starting with a RaspPI or Arduino prototype for the Kickstarter or something and then getting "real" dedicated hardware for production.

It is common to start with these before the Kickstarter, just to get a proof of concept, but those boards (and the ESP8266) absolutely aren't for production. Raspberry Pis are terrible since the only way to interface with them is over a single USB 2.0 port - and that's shared with the 100M ethernet and the SD slot. You might see an ATMega328p chip isolated, and that's "good enough" for hobbyist projects where you jus…

[deleted]
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