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Tell HN: Candles can make you feel tired
8 points by mkeespiet 1589 days ago
He there!

During evenings we burn quit some candles in our living room. Our house is well isolated (we have a heat pump for heating our house), so we have to ventilate a lot. During evenings we notice we got sleepy very early in the evening. When we go to bed we stay awake for quit some time. This made me wonder if there was a coloration with the candles and us feeling sleepy early, so I bought a CO2 meter.

After a few test it became clear that after burning the candles for like 1,5 hours the CO2 level was already 2 to 3 times higher than before the candles burned.

Maybe an open door: if you burn a lot of candles or are with a lot of people in a smaller room, don’t forgot to ventilate! This will make you stay awake longer!

6 comments

If you do anything that involves having an open flame indoors (and I'm including the flame inside a gas / propane fueled furnace, water-heater, etc., or a gas stove) you should have one or more CO alarms in your home as well. CO2 has its own issues, but CO is a very powerful asphyxiant and can very easily be deadly.

https://www.cpsc.gov/Safety-Education/Safety-Education-Cente...

I recently bought one of the best CO_2 meters available here (and had a CO alarm since before that): the low temperature boiler (natural gas, 1991) in our kitchen contributes close to nothing to the CO_2 level despite getting its air from inside. Letting it run on automatic a whole workday contributes less than 200ppm in our flat. But an adult and two kids can bring the level from below 500ppm to above 1000ppm in around one hour -- additionally: doesn't really matter if the doors to other rooms are open or not. Ppm fluctuation is (way) less than 100ppm between rooms.

(All time low 380ppm -- 10% above the world average during my birth :-( , highest 1620ppm)

Yeah, under ordinary circumstances your boiler or whatever should not contribute enough CO to cause problems. It's when something weird happens that you have to worry (usually). Like if the jet is clogged or something else happens that can cause incomplete combustion. Incomplete combustion is your enemy when it comes to CO[1].

[1]: https://www.abe.iastate.edu/extension-and-outreach/carbon-mo...

* I wrote about CO2.

* The boiler's flame is visible (through a slit).

* The system doesn't have a separate supply stream -- it takes oxygen from the flat.

An CO sensor seems obligatory to me: after the chemney sweeper (obligatory in Germany) measured 10,000ppm CO in the exhaust stream (defect, not normal operation), I didn't want to depend on a 25y+ boiler's electronics alone.

CO kills relatively fast. Even if rare, I don't want to die caused by a rare event that could have been avoided by spending ~50€ (here)

Get one that shows actual value.

We had one a new one that just beeps when high. Except it didn’t. Delayed medical treatment for months since it never went off.

Gas company guy showed us how high levels in house was and the alarm was silent. Even with fresh batteries.

Example? Surprisingly difficult thing to search for and seems an unwise thing to pick off amazon.
Well kiddie brand is the one that failed to go off. So not them.
Can come CO from candles as well? We do not have any flames inside as we cook with induction, we only use candles as indoor flames. Nice fact: Here in the Netherlands a fire alarm will be obligated starting from this summer
Yes, any combustion will produce CO as a byproduct. Candles, fireplace, kerosene heater, the aforementioned water-heater, furnace, etc. And Carbon Monoxide is particularly deadly because it's a "chemical asphyxiant" meaning it binds more readily with the hemoglobin in your blood than Oxygen does.
Most candle wax is made from paraffin (derived from petroleum). More expensive candles made from beeswax won't be so polluting indoors, but a candle flame will always produce some soot.

An alternative is a fake LED candle with flickering 'flame'. All the ambience of a real candle without the noxious emissions! Of course, you still need a source of power, but LED candles can be powered by batteries and the battery power lasts longer than a wax candle melting.

Reddit had quite a story about CO poisoning. WBUR went on to summarize and expand upon it, making for a good (and somewhat alarming) read: https://www.wbur.org/endlessthread/2018/03/09/something-wick...
CO2 is the obvious connection here, but there's another effect at play. Candles tend to flicker in the 8Hz - 15Hz frequency range due to turbulence around the flame. This can be quite soporific. It's likely a neural entrainment. I wonder if LED fake candles that mimic the flicker have a similar effect.
There's no reason to burn candles, they produce particle pollution, add to co2 and reduce available oxygene while producing insufficient light.
not an expert, but isn't the sleepiness part the least of your problems in that situation?
IQ drops a lot with Carbon monoxide.

Perfectly obvious stuff like “I’m being poisoned”, doesn’t occur to you.

If its because of carbon monoxide building up in the room, it's a pretty big problem.
I think that might be what the user is alluding to