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On whether changes in bedroom CO2 levels affect sleep quality

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Re: On whether changes in bedroom CO2 levels affect sleep quality

#291

Post by darkpuma »

abootstrapper wrote: post #213
darkpuma wrote: post #81

Earlier quoted context omitted.

If you believe that is a serious concern in your area, get bars for your windows. There is no shame in it, I've lived in numerous buildings that had barred windows. However I suspect that most people don't sleep on the ground floor (either in a multi-level house, or in an apartment building) so for them this should be less of a concern.

Bars on the windows? Now we're back to fire safety.

Yes I considered that and I was curious, so I looked it up. It seems the federal government estimates a lower bound of 25 people injured or killed in fires due to bars on windows every year. All things considered, I think that's not so extreme, although the risk should be weighed against the relative risk you believe burglary poses in your neighborhood. 25 per year is several orders of magnitude lower than the number of victims of violent crime stemming from home invasion, although many neighborhoods will not embody those averages.

https://www.usfa.fema.gov/downloads/pdf/publications/tr-138....

https://www.bjs.gov/content/pub/ascii/vdhb.txt

There are other solutions as well. Many window frames are designed to permit the window to be cracked open but not opened fully, to prevent ingress while still allowing egress (either by disengaging the mechanism or by breaking the window if necessary.) Such a mechanism can often be retrofitted to an existing window frame for no more than a few dollars. I've seen people create their own using a short length of dowel rod placed such that it prevents the window from opening fully. There are also a variety of purpose made mechanisms on the market.

These mechanisms are not as secure as bars on windows, but about as secure as a normally closed and locked window. The payoff for less security is enhanced aesthetics and fire safety.

There are many reasonable solutions to bedroom ventilation.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#292

Post by AstralStorm »

pkaye wrote: post #49
DocG wrote: post #29

I was lucky to get my hands on 5 proper co2 sensors from university, while I was teaching and working. So plenty of test places. What I found: -Just a couple of hours in a office, without ventilation spikes the co2 enough to make everyone dizzy and tired by the end of the day. Keeping eye on the meter and ventilating properly, increased everyones productivity and people werent so tired by the end of the day. - Classr…

Air tight buildings need a heat recovery ventilator.

Any ventilator. Heat recovery is optional - it is really hard to recover heat from lukewarm air without actually recirculating most of it.

The pressure drop requires more electricity due to more power in the pumps, making it a relatively bad trade - only heatpipe systems are worth anything.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#293

Post by AstralStorm »

lomereiter wrote: post #111
treis wrote: post #97

Earlier quoted context omitted.

Theres no difference in heating efficiency for any source. Heat is heat and it doesn't really matter if it's generated from a heating element in a furnace or an LED light. And with the light you're at least getting dual use out of it. If they have a gas furnace it might be different but that would also depend on how their electricity is generated.

Your statement is true if the electricity is generated locally, otherwise there's a difference in energy losses depending on the carrier. According to http://web.archive.org/web/20180822025250/https://portfoliom... heating with grid electricity would require 2-3 times as much primary energy as heating with water/oil/gas.

Especially if you have central heating.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#294

Post by SketchySeaBeast »

throw0101a wrote: post #287
SketchySeaBeast wrote: post #275

Earlier quoted context omitted.

The highest BTU heat pump I see is 46,000 - that's not going to be a solution for a lot of homes, which need 30,000 / 1000 sq ft, not to mention loss in efficiency as the heat drops so you're getting less than that when you need it the most.

How much you need to heat/cool a home is more of a function of its level of insulation and air tightness than its mechanical capacity. It's possible to design house that need almost zero BTUs: * https://en.wikipedia.org/wiki/Passive_house When looking at bang-for-buck / value / ROI, better insulation and air sealing should be done first. If you can reduce the number of your blower door test, then you'll have to spend…

Passive houses are cool, but most houses aren't, and can't be retrofitted to fit the requirements.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#295

Post by diminoten »

colechristensen wrote: post #201
John_KZ wrote: post #130

Earlier quoted context omitted.

I'm impressed by how low the score of your comment is. I know computer scientists aren't "real" scientists but I thought the lack of rigor in this one was apparent and it was only upvoted only as a conversation starter. I guess I was wrong.

There wasn't a "lack of rigor" He just never finished. He collected data and then didn't follow up with graphs and conclusions and such. There's nothing wrong with a blog post that tells you about 2/3 of a N=1 study on yourself, it's interesting. It doesn't owe you completion, it just is not complete.

There is a distinct lack of rigor, and there's a lot wrong with a blog post that doesn't accurately describe the environment the experiment is taking place in or any other pertinent details that would allow for a reproduction.

Completion is actually the least of the problems here.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#296

Post by diminoten »

your-nanny wrote: post #206
colechristensen wrote: post #201

Earlier quoted context omitted.

There wasn't a "lack of rigor" He just never finished. He collected data and then didn't follow up with graphs and conclusions and such. There's nothing wrong with a blog post that tells you about 2/3 of a N=1 study on yourself, it's interesting. It doesn't owe you completion, it just is not complete.

it's also funny how people assume blog posters owe them anything. get off their lawn!

No one owes me anything, but it's posted on HN and there's a comments section in HN so I am entitled to point out the (substantial) flaws in the submission.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#297

Post by throw0101a »

AstralStorm wrote: post #289
throw0101a wrote: post #288

Earlier quoted context omitted.

That draft you feel is money going out the (proverbial) window. It's better to stop the air going in/out through walls, doors, and windows, and bring it in in a controlled fashion: * https://www.youtube.com/watch?v=CIcrXut_EFA The problem is that many retrofits don't bring in outside air into the mix and just recirculate what's already in the house. This is not current best practice.

Any kind of air exchange will cause heat loss or gain, decreasing insulation. Does not matter if it's through wall or HVAC. If there is no draft, it means there is no air circulation. The only difference is if the draft goes through HVAC vents or through unsealed doors and windows, or through walls. If your local heaters are effective and seal controllable, there should be really no difference in many municipal setti…

You're not wrong, but one can mitigate energy loss with an HRV (or ERV) and get fresh air in a controlled manner:

* https://en.wikipedia.org/wiki/Heat_recovery_ventilation

With the added bonus that the air can be filtered as well, instead of coming in as-in through leakage.

Re: On whether changes in bedroom CO2 levels affect sleep quality

#298

Post by manmal »

sinuhe69 wrote: post #222
manmal wrote: post #48

FWIW, I have almost no dream recall, and am not as rested, when the window is sealed shut. We are four humans and two cats (usually) in a small-ish bedroom, creating a lot of co2. There is built-in ventilation in each room, but performance starts declining 2 weeks after every filter change (which cost €20). So I swap the filter only once every 1-2 months, and instead open the window ever so slightly (moving the lever…

I live in a tropical country and I always prefer to sleep with open Windows. The only problem is the noise. I believe noise affects the sleep quality as much as well. Earplugs might be a solution but I don’t know any good brand which are comfortable enough for long time carrying.

It seems there will soon be a mass market solution: https://www.haaretz.com/israel-news/business/sick-of-the-noi...

Re: On whether changes in bedroom CO2 levels affect sleep quality

#300

Post by thatcat »

hnick wrote: post #224
clairity wrote: post #142

Earlier quoted context omitted.

ha, i actually bought a bunch of plants from the nasa list a year-ish ago to help reduce co2 & voc levels: https://www.healthyandnaturalworld.com/best-air-filtering-ho...

Did you notice a difference? We have a small office with two people, multiple PCs, printer, etc. It gets warm and stuffy regardless of the season and climate control, and I have trouble focusing especially in the afternoon. I'm thinking of picking up a plant or two and pointing a fan at the door to send out some of the stale air.

To get a better filtration effect you need to force air into the root zone through an active carbon layer in the soil media. That is the method used in the original nasa paper and subsequent public labs designs when trying to remove VOC's such as those emitted by printers. Active carbon adsorbs the VOC's so that the root microbes can metabolize it. Since it is a microbial filter, it becomes more effective at filtering the contaminants that it's most exposed to. Active carbon can also remove CO2, but must be recharged with lower CO2 air periodically.

The public labs design uses a aquarium bubbler to push the air, but the flows are pretty low - with retention time in my 10x12 office at 1 month. Since the VOC's are usually heavier than air, if you place the pump inlet on the floor it performs better though.

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