A candle produces roughly the same amount of energy as a resting human
twitter.com
twitter.com
A candle produces roughly the same amount of energy as a resting human — 80 to 100 watts, also consuming about the same amount of oxygen and producing the same amount of CO2. In an enclosed area, adding candles is about like adding people from an air quality standpoint.
https://www.google.com/search?hl=en&q=detecting%20a%20hydrog...
https://youtu.be/g3Ud6mHdhlQ?t=738 (linked to correct timestamp) shows the remains of a burned one and loading fresh ones on a submarine.
As my bathroom walls can attest to. It took a long time to clean that up. I don't use candles for scent any more. Now I just keep them as one of many sources of emergency light and heat.
Keeping the wicked properly trimmed to ~1/4 inch makes a huge difference in keeping soot emissions down. There’s a reason store-bought candles always tell you to trim before burning!
If the flame starts to jump and flicker (in calm air), the wick is too long. You can see big sooty plumes be thrown off when this happens if you look.
I bet this was widespread cultural knowledge in the era when candles were the primary method of indoor lighting.
Melts the wax and gives you that lovely smell without any fire. The wax also lasts much longer in one of these than in candle form.
_Overall_, outdoor air pollution (coal/oil/industrial effluent/etc) kills more (about 4.2 million) but in terms of single worst cause, cooking with biomass seems to be it.
Even in many rich countries, wood (generally burned for heat, not cooking, in the rich world) is one of the biggest sources of particulate air pollution, as coal is phased out and vehicles get cleaner.
welcome to my family
Also s/produce/release/g
Really, humans are the health concern we should be paying more attention to.
OT: speaking of the bird site...how does it decide what to recommend in the "More Tweets" section? I'm kind of baffled by the stark differences between its recommendations on two recent visits.
Yesterday I followed a link to a Paul Graham tweet. Then I scrolled down to see what else Twitter recommended. It was full of right wing conspiracy theories, climate change denial, anti-vaccine stuff, one about Bill Gates' plan to depopulate the world, and of course something about the Jewish bankers that control the world. There was almost nothing that wasn't similar to the above.
Today I go there to view this John Carmack tweet, and what Twitter is recommending is a tweet from Joe Biden, a Greta Thunberg tweet, a tweet about the Formosan clouded leopard being declared extinct in 2014 after no sightings for 40 years but then was spotted in 2019, an Edward Snowdon tweet, a tweet from the National Park Service, various humor tweets, a tweet about a lecture on how to build GPT from scratch, and a couple about business acquisition. There were a couple of right wing political tweets (from Scott Adams and Glenn Beck) but they were mild and about Musk so I assume that's why they are there. There was also one from Andrew Tate that was a pretty good inspirational statement and did not mention Musk at all. Oh and this great but best not read if you going to sleep soon tweet "16 of the creepiest paintings ever made" [1].
Is this difference because of Twitter's inferences about the kind of people that read Paul Graham and read John Carmack? I'd guess Graham is more to the right than Carmack but from what I've seen not anywhere enough that reading Graham is any kind of signal that you would be interested in the kind of conspiracy theories and such that it was recommending yesterday.
[1] https://twitter.com/culturaltutor/status/1615648152983572480
The echo chamber is real. For all its potential, Twitter is no way to learn about the world. But the same goes for any web site with algorithmically served content.
The perpetual internet carousel
Having the text here instead of linking to an appallingly bad website should always have been the norm. But nooo, we had to wait for Elon Musk to buy the thing.
*: Wattage might be the same, but the effect on air quality is different. Humans don't exhale carbon monoxide and smoke.
Both consume oxygen, which is certainly part of "air quality". But the lesson could've been narrowed down to just oxygen, "air quality" involves other things. Seems main takeaway is that one candle = one human, wrt. oxygen in the room. If the numbers are right.
To ignore the the central subject of the comment - air quality - in order to call it "not incorrect" is doing quite a bit of work.
> Seems main takeaway is that one candle = one human, wrt. oxygen in the room. If the numbers are right.
If we can ignore air quality, what is the difference between this and the comparison between 2 60lb dogs and a human in a room? Or any other animals of similar mass that respirate in the same way?
Clearly the comment was an overtly reductive missive targeted at recent concerns about air quality issues created by indoor combustion.
Then how is his comment topical or even interesting? It sure sounds like he's wading into the indoor air quality debate that ignited (pun intended) around gas stoves in the last week. But as others have noted, he's a "great man" so his opinions, well informed or not, get broadcast.
That surprised me. Reading this adds to that feeling of surprise, and gives a clearer idea of how much heat they emit.
I say it's a good post, if one reads it right. (It must be clear to most people that it's taking shortcuts in reasoning about air quality, so you must be mindful of the context you apply this to.)
If you ignore the numbers you can still easily feel the heat, but it's not so easy to translate into human equivalents.
You can get a large range of wattages for one socket size.
The average person, when asked how many watts that bulb is, is probably going to say "60" or "much less than 60 but I don't know how much".
I've noticed I sleep better when I sleep separately from my wife. I'm the more violent sleeper, so it's not movement related, so I'm wondering if it's air quality related.
If possible, keeping a bedroom window a bit open makes a noticable difference. Avoid closing bedroom door too.
Similarly, if you work from home, make sure to create a draft once in a while.
We got an Aranet4 CO2/humidity/temperature sensor mostly out of curiosity two months ago. Outdoors it's ~430 ppm CO2. 500-1000 ppm indoors is considered okay (according to the defaults), 1000-1400 ppm high, and >1400 ppm bad.
It's amazing how you don't notice how it slowly creeps up to 900-1000 and beyond. Without the device I would notice, except that I'd slowly get tired. I'd probably also drink more coffee. The device helps you see what's going on and how bad it is. Creating a big draft for 5 minutes clears everything out.
Also, you can definitely see from the historical data when one goes to bed in a ~12 m2 bedroom and then an hour or so later the second person goes to bed. Same if one gets up before the other. Definitely good evidence that keeping a window open is a good thing (if you got clean air outside)
It's currently really cold where I live, and I am trying to limit outside air coming in as much as possible. This then leads to the air having uncomfortably high levels of CO2, as confirmed using an air quality sensor.
Good insulation only works with good ventilation anyways, the goal of insulation isn't to make an house completely airtight
Look into these things: https://en.wikipedia.org/wiki/Heat_recovery_ventilation
It has made me notice "stuffy" air more keenly and helps me avoid it. If I'm stuck in a physical meeting room at work I take lots of walks and breaks. etc.
I haven't tried the CO2 sensor in the bedroom. We like to sleep with fans on and the bedroom door open, which I suspect helps somewhat (depending on how drafty one's house is overall) although is obviously not as effective as having a window open.
The average person exhales about 1kg of CO2 per day. That's 542L per day. Let's say you produce 20% of your daily CO2 output during the night, since your metabolism is lower when you're asleep. That would be 108L per person per night, or 216L for two people.
The average American bedroom is around 120-130sqft, or 11-12 square meters. Assuming a height of 8 feet, the total volume of your bedroom is around 25-30KL. Pumping 216L of CO2 into a sealed room of that size will result in a CO2 concentration between 720 and 864ppm. That's not high enough to cause immediate medical problems, but it might have more subtle effects, especially if your bedroom is small or if your metabolism is higher.
720 and 864ppm is probably the lower limit for a completely empty room.
CO2 measurement gadgets are useful for measuring how stagnant your air is, but the above parcel of questions is a great predictor: if your answers are No for all questions, then you’re probably spiking CO2/humidity uncomfortably high at night.
Changing any of those answers from “No” to “Yes”, in any way that increases the amount of indoor air exhausted outdoors from your bedroom, and/or outdoor air drawn into your bedroom, may help a lot.
Measuring relative CO2 levels using daily graphs from a gadget is an excellent indicator of whether any change had an effect.
The EPA page on indoor air pollution monitors: https://www.epa.gov/indoor-air-quality-iaq/low-cost-air-poll...
If you do have a problem companies such as E. L. Foust Co. sell air filtration systems and HVAC filters which contain mixes of activated carbon and various minerals to reduce indoor air pollution. The one we've got is marketed for 500 square feet and eats 75 watts when on, so I'm not sure the plus/minus on the energy efficiency. Still, if you live in a place with wildfires or industry it is useful even if you lived in a non-sealed house.
1. https://en.wikipedia.org/wiki/Energy_recovery_ventilation
2. Schematic picture: https://www.panasonic.com/nz/hvac/products/energy-recovery-v...
1. It's John Carmack.
2. It's "sciencey".
3. It (his assertions) seemed slightly "under informed" or vague, and I wanted to see what the HN crowd had to say given the wide array of expertise.
So happy to see it climb to the front page to see this debate pan out!
Another benefit is my head stays cool which I find more comfortable
Aren’t there some that actually produce oxygen?
Yes, oxygen candles are a thing. Check out the MSDS for one here: https://www.msdsdigital.com/system/files/85984.pdf Summary: It is neither particularly safe nor advisable to store oxygen candles around the house. Let alone use them.
And years later, I learned that was exactly what the earlier drafts of the script said. They changed it because the studio execs thought the audience would find the concept confusing.
Perhaps we should be encased in sterile bubbles at birth, with all inputs filtered for purity and consistency. Surely that would be the best way to avoid all the dire consequences of the pollutants surrounding us.
By outbreeding the fact that we also died a bunch for unknown reasons.
And I think this tweet is actually a fairly calming view on things. I wouldn't hesitate to share a room with a couple extra people, so I won't worry about a few candles occasionally, because they're a nice benefit to the space. Meanwhile it's an absolute no-brainer (for me and many other people) to avoid gas stoves, because they don't have any ambience benefits and my local power grid is quite stable.
Living in bubbles might be biologically safer, but we're also creatures that need to live, so it's not a tradeoff most people would (or should) accept. We can make gradual incremental change as we learn more though, and we should try to do so.
Except that all the concern around gas stoves is mostly BS. The issue with cooking is not the heat source, it's actually the fumes from cooking itself. The ONLY safe way to cook from an indoor air quality perspective is to have a properly installed externally vented range hood (and makeup air if needed). It doesn't matter if you use induction, radiant, or coil electric, they all produce just as much cooking fumes as gas, and the gas burning has a negligible impact. I've confirmed this myself many times over with calibrated sensors.
The worst thing about indoor air quality in the US is that the US doesn't require external venting in kitchens by code, and it should. The PM2.5 spikes in nearly every American household the moment someone starts cooking, and to dangerous levels for the person doing the cooking. American houses also have horrible ventilation generally, with newer houses being even worse as they get better sealed for efficiency, but without being required to provide active ventilation. It should be legally required that every home, including rental apartments, be constructed with an externally vented range hood and an energy recovery style active ventilation for fresh air exchange.
I challenge folks to improve their indoor air quality and see how much it benefits them by simply opening your windows up at least once a day (which unfortunately isn't the most energy efficient thing to do), and finding a way to actively ventilate your kitchen when you cook (if nothing better, a box fan in an open window is not a bad way to go. recirculating range hoods do nothing).
> I've confirmed this myself many times over with calibrated sensors.
This really means nothing considering that rigorous studies and metastudies [1] have been performed and the results published that demonstrate the opposite: that gas stoves result in CO and other harmful emissions that electric stoves don't, independent of what is being cooked. Those studies aren't a global conspiracy against gas stoves. If you have similarly published your data and it has been reviewed, please do share it with the world.
> The worst thing about indoor air quality in the US is that the US doesn't require external venting in kitchens by code, and it should
I agree wholeheartedly, but the problem doesn't end there. Most range hoods in single family homes are externally vented, but there is a behavioral problem, which is that most people use the kitchen hood vent as a way to exhaust smoke odors only, usually only in response to a smoke alarm going off. Even worse, after enough rounds of this, many people end up disabling the smoke alarms near their kitchen rather than taking it as an indication that there is an air quality problem.
If the only effect of these studies is to alert people to the necessity of turning on their hood vent and opening a window for makeup air every time they cook, especially on a gas stove, that's a win.
I wish this were true, unfortunately it's not. Most homes in the US, including freestanding SFHs, use recirculating range hoods.
> that gas stoves result in CO and other harmful emissions that electric stoves don't, independent of what is being cooked.
This is true. It's also a negligible difference, and mostly immaterial if you are externally venting fumes when using the stove. The biggest issue is not the carbon monoxide and other emissions, it's the particulate matter that is given off when cooking, which happens quickly during cooking and irrespective of heat sources. Consistently breathing in high levels of PM2.5 has severe health consequences, including increasing risk for lung diseases and cancer, even when the particulates themselves are not carcinogenic. What's worse, many particulates given off when cooking /are/ carcinogenic, such as when searing meats.
Ventilation is the most critical aspect here. There are more important safety reasons why people should avoid open flames and direct heat in favor of electric induction, as well as environmental reasons as all-electric homes can be powered using exclusively renewable energy sources, these are much better arguments against using a gas stove than the air emissions, which are insignificant compared to cooking fumes themselves and both need resolved via ventilation.
> there is a behavioral problem, which is that most people use the kitchen hood vent as a way to exhaust smoke odors only
Agreed. One of the challenges in the US is that because most range hoods are recirculating and not vented, especially in rental/cheaper properties, people become effectively trained to not use it because they are very loud and not effective. Externally vented range hoods are both quieter and are actually effective, and train people to use them once they're exposed to them.
> many people end up disabling the smoke alarms near their kitchen rather than taking it as an indication that there is an air quality problem.
This is a real issue, and a big issue for fire safety as well. Most American homes also don't have carbon monoxide or carbon dioxide monitoring, both of which are major issues. We also have significant exposure to radon in the US, and no state currently legally requires landlords to provide mitigation and testing for radon.
There are myriad indoor air quality issues in the US, and proper ventilation can solve or mitigate almost all of them, and when it's present it does not train bad habits and may untrain bad habits.
We must have very different anecdotal sample populations of single family homes, because I've only ever seen the recirculating types in condos and apartments, where they are done that way due to space/ducting constraints. But there is very little data available on this question. The closest I found was in this study relating specifically to California:
"A survey-based study of 1448 detached houses built in 2003 reported that 80% had range hoods exhausting to outdoors and 4% had downdraft ventilators, while 13% had recirculating range hoods and 3% had no range hood or did not know [34]"
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7729668/
Those stats echo my own observations in two places: California and the Midwest. But it's possible that it's completely reversed in other places. Building codes can vary a lot, after all.
I completely believe that recirculating fans are more prevalent in low-income resident properties, though. That's also something I've seen extensively.
> Externally vented range hoods are both quieter and are actually effective, and train people to use them once they're exposed to them.
People are really bad at diligently doing inconvenient things, even if it means an improvement in their health. My dentist is always on my case about flossing more, but I end up starting up a week or two before my cleaning. Also, we are bad at evaluating invisible or quotidian risks, which is why many have an incorrect understanding of the risks of flying vs driving.
The long term solution to this problem is to require automatic makeup air ventilation systems for all kitchens in the codes, but that will probably be a long pull. As for indoor gas stoves, I imagine with time they will have the same trajectory as ICE cars. Remember that gas stoves were once the novel high tech replacement for wood and coal stoves, and also on the basis of the improved health and convenience, just as induction is today.
Not sure about ambience, but pita bread heated directly on the flame of a gas stove cannot be beat. It’s faster and more delicious than any electric toaster.
We shouldn't thoughtlessly make gradual changes which sacrifice quality of life for safety (which is the direction that these changes always seem to go) without actually deciding that the benefits are worth the costs.
The answer IMO is "yes, if the number of deaths is small enough relative to the total amount of pleasure that the pretty lights create", but without a quantitative framework it's pretty tough to make that call.
You really do the robustness of the human body and immune system a disservice.
If you want any more than that, you should do what you can to help it along, including avoiding known harmful substances where you can.
Surely you mean avoiding dangerous electric stoves, which emit hazardous electromagnetic radiation?
Edit: Yup, everyone bit. Christ you're a bunch of dafties.
The "electromagnetic radiation" from stoves has not been shown to be harmful in the amounts absorbed during cooking.
Particles in the air _have_ been shown to be harmful, even ignoring CO and gas leak risks from gas stoves.
Right, but they don't generate CO and they don't leak. If they do, they are faulty and should be repaired or replaced.
Don't you have safety inspections where you are?
[1] https://emfguardtips.com/do-electric-stoves-emit-emf/ [2] https://sciencing.com/strong-standard-magnet-6853786.html
1. You don't understand something
2. Someone tells you that you don't understand
3. Got you good, can't believe you fell for my ignorance
Can you point out what you think I don't understand?
I don't know what this is supposed to mean.
Can you point out what you think I don't understand?
Electric stoves don't give off harmful radiation.
Yes, that's the joke. You got whooshed. Don't worry, it happens.
At LTE and WiFi frequency bands, it can be used to spread a great deal of misinformation.
People concern for "Germs" lately has me wondering how in the world humanity survived to this point, in utter ignorance of the horrid damage everything they could touch was doing to them.
Perhaps we should wash our hands with soap, with all inputs filtered for purity and consistency. Surely that would be the best way to avoid all the dire consequences of the pollutants surrounding us.
> snarky, reddit-style tone.
I share the blame there. Sorry. I'd like to make the point in a better way, but im busy and my hands hurt, so i said this and hope some are amused as much as annoyed.
People concern for "leaded gasoline" lately has me wondering how in the world humanity survived to this point, in utter ignorance of the horrid damage simply being near a car is doing to them.
Historically, there have been issues with coal and air quality.
https://en.m.wikipedia.org/wiki/Great_Smog_of_London
Now that we have 8 billion people on the planet at once, even a small human footprint adds up.
[1]: https://www.manchestereveningnews.co.uk/news/nostalgia/manch...
[2]: https://old.reddit.com/r/powerwashingporn/comments/6d3l6p/th...
2. there was, in some regions, lots of living indoors with fires and candles and sleeping with animals, because they had no other choice, and they died in their 30s or 40s at best anyway so it didn't really matter. Probably breathing soot all the time while indoors was part of the reason they died in their 30s and 40s a lot though?
3. In the distant past a moderate IQ drop due to particulates wouldn't have been as big of a hindrance to survival and success as in the modern world, perhaps. I see lots of hints that even small shifts in a societies IQ in the modern world has pretty dire consequences. I'd love for that to be investigated more.
"Lately?" People have been worrying about air quality ever since it became clear that poor air quality was killing people (mid 19th century), and have been legislating it since then.
Now, the biggest killers have been mostly legislated out of existence in developed countries (with some exceptions around big old coal plants, which can cause serious regional problems), and attention is turning to those that just knock of a few tens of thousands of people a year, rather than the millions of yesteryear.
Simple. By living in extremely drafty and effectively open-air structures. That had other tradeoffs though.
I upvoted your comment because I, too, am tired of the constant doom and gloom rhetoric. It turns out that practically anything and everything we are exposed to as we live our lives can have negative effects on us.
I'm gonna keep using scented candles, and if they want to be the death of me, well, they will just have to get in line behind basically everything else on this planet.
constant doom and gloom rhetoric
I view it more like performance optimization. Clear correlation between CO2 levels and cognition. Clear correlation between "air quality" in general and health. I try to optimize for those things when possible. When I deviate from that I'd at least like it to be an informed decision.
Do you think there's a happy middle ground between "doom and gloom" and "utter ignorance?" I do. Many of us find knowledge more comforting than ignorance.
I still use my gas stove. I'm just more conscientious about it now. Candles... yeah I don't use them enough for it to be a factor. Hell, I even burn incense sometimes and that's literally designed to flood the air with particulates. (Japanese incense burns a bit more cleanly, FWIW)
I just like to be informed, I suppose.
I'm gonna keep using scented candles
and if they want to be the death of me, well
Nobody is claiming that's bad or that you shouldn't use them, and certainly not Carmack in the linked tweet.
If you've willfully misinterpreted his tweet as "doom and gloom" or "candles are gonna kill us, don't use 'em" than that is a very conscious choice you have made, and one unrelated to reality.
Are you not reading all the other comments on this thread? Haha. They might not be outright saying "don't use them", but there are several comments in this thread that say 'if you use candles then you don't care about improving health safety.'
I certainly get that vibe from a lot of the comments here, even if I detest scented candles and wish my partner would stop using them!
Only one I see is maybe dekhn's post: https://news.ycombinator.com/item?id=34427789
But because someone says that "candles produce soot and other molecules which have been shown to be harmful", it doesn't mean the speaker is in a doom and gloom mindset: that's an interpretation you make.
Also understanding of problems caused by this and availability of alternatives increased.
We can see how life expectancy improved in areas where pollution was reduced.
In the end you could mind the survivorship bias. Sure, people survived through the past, but many had earlier death due to pollution.
Technology has improved this in areas that adopt it.
should we remove all public health interventions, like sewers, drinking water standard, seat belts, any kind of transportation licensing?
sorry, that's a logical fallacy, and is not helping anyone.
But, improvements to society can be disruptive. The move from coal gas to natural gas was a marked improvement in safety, but was mildly inconvenient for a few years.
Ensuring that every dwelling had a toilet and bathroom attached to the house was expensive to implement, but now its taken as standard.