Frying Eggs and Air Quality Tests
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Air QualityCookingIndoor Pollution
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Air Quality
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Indoor Pollution
The author tests the air quality while frying eggs and finds minimal impact, sparking a discussion on the effects of cooking on indoor air quality and the factors that influence it.
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> PM2.5 peaks at 11 ug / m^3 and then comes down once I stop frying.
? Just saying "Contrary" doesn't give away much information.
It doesn't come down when you stop frying? It peaks at a different number? It never goes up at all? It actually goes down when you start frying?
Try cooking with oil and you'll see PM levels go to enormous heights.
That's not to say you should go out and buy everything coated in PTFE. It generates tons of pollution when it's synthesized. I'm just saying there's no need to rush to throw away the ones you may already have at home - that might be counter-productive as you're now generating waste unnecessarily.
But who knows, maybe those pans are even more dangerous than currently known.
https://en.wikipedia.org/wiki/Tempering_(spices)
When I start cooking downstairs, within a minute or so I hear the purifier upstairs ramp up to full speed.
Were they talking about gas hobs? Surely that's much worse than the electric/induction one you appear to be using.
It produces CO2, NO2 and some CO. But it's not going to show anything on a PM2.5 meter.
The particles when frying come from the oil turning into smoke, as well as just aerosolization even well below the smoke point. These are what send PM2.5 levels skyrocketing.
When I sear a steak in cast iron, my PM2.5 levels go from their baseline of ~2 ug/m^3 to ~200–400. And course you can smell it in the air.
Also, cooking of all kinds spikes PM levels in my experience. Maybe eggs in a 100% clean non-stick pan are an exception, but I doubt it if you can smell it.
Surprisingly, making the bed, shaking out the sheets, or vacuuming doesn't make it change color.
But farting in the room makes it red for minutes.
An ever amusing phenomenon that makes my girlfriend and I chuckle on a weekly basis.
Some other air purifiers like Coways measure particle pollution.
But it pretty consistently sets off the Coway air purifier in my kitchen when I do it...so I would assume frying with oil to the point of smoking does adversely affect air quality.
.... That should be obvious though, right?
My one wish is the west adopted Chinese style kitchens. Even in new condo builds the kitchen will be isolated in a room you can close off, with an exterior wall and powerful exhaust vents. I always found it perplexing how ok folks are with what feels like cooking food in their bedroom.
Aside from studio apartments, where space is at a huge premium, I'm having a hard time understanding what you mean by this. Can you elaborate?
I also don't think "you cook and the whole house smells" fits the analogy of "cooking in your bedroom". The key feature of the bedroom is that it's where you sleep, get dressed, etc., not the smell.
Weird hill to defend when you don’t even have data. Maybe you did not like my analogy but it also matters how much you cook and what you are cooking. Hence why it can be more important in a Chinese household, lots of high heat cooking of meats including fish. So I can see the analogy failing in a household that does not cook often or cooks more tame items. If you frequently cook fish, or do any type of high heat, heck if you have done any cooking in a commercial kitchen before you quickly realize how inadequate the venting is even if it does go outside. Hence it can feel like you are cooking in your bedroom in a lot of western houses since they use an open floor plan with the kitchen. But ignore the analogy if you don’t like it!
https://pmc.ncbi.nlm.nih.gov/articles/PMC10234804/?utm_sourc...
The link you've provided says nothing about hoods generally not being in western homes or make your analogy any more apt.
I never claimed hoods don’t exist, just that they’re often inadequate. And yes it’s wild to me that 10% of homes don’t have a hood and the other 30% or so are recirculating air which is close to the same. Whether the analogy clicks for you or not, it reflects the lived reality of anyone who cooks frequently (especially with high heat or strong flavors). That’s why Chinese-style kitchens, with closed layouts and strong direct venting, are so valued.
If your rebuttal boils down to “but bedrooms are for sleeping,” then maybe this discussion is not valuable.
Why do people insist on defending the oddest of hills over such a lived experience comment like the one I made. Now for sure if you rarely cook or if cooking is making Mac and cheese then sure this will be hard to understand.
I was trying to understand your analogy, because, having cooked in western kitchens and been in bedrooms (often in the same house!), it made no sense to me. It's not like people generally sleep in their kitchens. Your reasoning seems to be that cooking makes your house smell. Even if this is true, I still don't see how this makes your kitchen feel like your bedroom.
Then you talked about hoods, with an undefined "adequacy" measure. I correctly suspected here you were going to use this undefined adequacy measure to move away from the analogy about cooking in your bedroom (presumably because it is inexplainable) to start a separate argument and take it wherever you needed to. You found some study (about Canada, but there's a lot of "West") that talks about hoods (being found in 90% of homes). But you see, some of these hoods are not adequate enough... sigh
OK, all that is beside the point, because again, what does any of this business about hoods have to do with bedrooms?
If you can’t grasp that distinction after multiple explanations, then maybe the analogy isn’t the problem. Happy to discuss if you actually have anything constructive to add but please your beating a dead horse for no reason.
If the exhaust mechanism is attached to an above the range microwave, it’s not adequate. And that is the vast majority of kitchens I see on Zillow, and I have probably sifted through thousands and thousands of houses.
A dedicated exhaust hood is seen in very few home listings, mostly in new higher end homes, or older renovated homes.
A lot of 90s+ builders are trying to prevent any and all air leaks, many with the idea of insulation, with the outer vapor barrier system already blocking 90% of what would get through on and older house, on top of the fastest building process being sealing every visible seam and line with caulk instead of trying to cut and match it up perfectly. And any overall airflow problems are quite literally not their problem, that all goes onto the HVAC guys/company or lack thereof, which often these days are the cheapest possible corporate scrapings for employees that only have half a clue what they are doing and only really care about whether the system turns on or not as per the system manual.
And in many places the hood doesn't extract outside but just filters and blows back in the kitchen. Even less efficient.
In modern buildings you get these together: an open kitchen meant to make the living room look more spacious and a hood that and just spins the air around a bit because it can't blow it outside (it's nowhere near an outside wall, or you can't just drill a big vent, or mess with the air circulation). The smell will go to every place that didn't have the door closed. Don't get me wrong, the smell of good food is great, but not when it gets in your dresser full of clothes or when the house gets saturated with a cacophony of smells very difficult to remove.
It has a fan to pull smoke and steam up out of the cooking space.
It blows the fan output right in my face, rather than outdoors.
This does not contribute anything useful to the cooking process.
It's fairly common in America. It's so common it appears it doesn't even cross your mind to consider it as something that might be desirable or useful.
(For those who say "well fix it then", I've looked, but unfortunately if you just put a hole in the wall behind the fan you end up in another exterior wall that meets up with the house there. It's not an easy cheap fix.)
If we can't come up with something a little more scientific I'm happy to send my wife over to do some cooking!
The effectiveness of the range hood directly impacts how close you can be to the stove before your eyes start burning and watering and you start coughing a lung out because you've effectively been hit with pepper spray.
In the worst case scenario (no range hood or ventilation), you'll probably want to evacuate the house.
As the person you replied to says as well, the popularity of "open concept" spaces contributes too. Even with poor ventilation, a kitchen with a door you can close helps limit how far the cooking byproducts reach.
I am from the west, have lived all over the US and no there is not great data on the matter but I have historically had an interest on air quality and I cook a lot. There is some nuance to the data. 10% reported not having any hood. 26% of gas households were not vented. 36% of electric were not vented. You can start going down that path and also start seeing that most vented hoods are either inadequate or don’t properly cover the cooking area.
So I am not sure what you are trying to argue about? There is a non-trivial amount of homes in the US without proper ventilation. You can pull up Zillow almost anywhere in the country and easily find center island cooktops without hoods or down drafts. Or even more common a microwave recirculating that air.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10234804/?utm_sourc...
So right off the bat, you're down $20k at least to remodel the kitchen so it has proper ventilation, assuming you cook.
Forget the health effects and whatnot, but are people not bothered by cooking smells pervading the house?
Cumin, Turmeric, hot onion and garlic just fragrant, butter, creams...
What do you think food should smell like? Boiled chicken? Do you have sensory issues?
Baby octopus fried in fish sauce stink, even with a vent fan.
Plenty of dishes, and entire cuisines, need good ventilation.
Being very honest, no, not really. From all the issues I can encounter in a house the smell of a meal cooking is not one of them.
On the flip side I am thinking about anything with high heat, meats and oil. The food will be delicious and the smell of the food is great but the smell from the cooking process is miserable and will linger.
Personally I would prefer a Chinese style kitchen with a fully enclosed cooking space (sliding glass doors to leave open if desired) and exterior ventilation. It keeps the worst of the aerosolized oil contained and away from the rest of the home.
In France too, most kitchen are optimized for looks with an island and fully opened to the living room. If you use noisy equipment, it makes both places uncomfortable. But I think that's the point, it doesn't happen that often.
There are not a whole lot of people who actually cook anymore and those who do deal with the annoyance or have their house choice influenced by that requirement.
I think complex home cooking is a vestige of the time when there were middle class housewives with a lot of time to actually do that. Nowadays with both parents working, cooking has been relegated to an activity that has to be fast, easy and efficient; which is why those multifunction cooking appliances are so popular. You never get something great out of it but it works decently enough to have the person responsible take care of some other errands simultaneously.
Biggest generator of pwm during cooking is when things actually burn. Which can be just a very tiny portion of the food, like one black speck that came off and heated extra. This produces more pwm than the mass of oil and food.
Often the problem is the exhaust path, not the extractor itself. Mine has a short straight path with a low resistance terminal cowl.
Try measuring PM2.5 in that room and log it as you turn on the fan for a while without cooking anything.
The air quality depends on exactly what you are cooking. Close the door if your cooking involves high heat, open it otherwise. And incidentally I don't understand why the author would do testing while frying an egg. Frying an egg does not involve high heat. High heat means getting close to or past the smoke point of your oil. I would not close the door when frying an egg.
A lot of people seem to like to knock a lot of holes in their kitchen walls making doors and shutters complicated and rarely used.
The chef breathes in the kitchen.
Food cooked in high heat often has additional related risks.
If you feel the need to condescend to the point that you're explaining what a door is please ask yourself if you're underestimating the intelligence of the person you're speaking to.
> A concept of a door is such that
It's just for comedic effect, or "performative erudition" in the words of a New Yorker reporter. No need to read too much into it. You have better things to do in life than to be offended so easily.
I laughed along with you until this...
But don't now tell me what I do and don't have time for. Do you have time to be so patronising in your life? What an ass
I've been on this site daily for more than a decade and a half and this is the first time I've ever felt it necessary to call someone an ass. I hope you have a bad night of sleep.
This works if there is a designated member of the household (whether family or employee) who prepares food away from everyone else.
It doesn't for a social setting. Fortunately, the only thing you need to reach the health benefits of the former in an open kitchen is a good vent. If you have a multi-story home, the motor doesn't even have to be in the kitchen, allowing for quiet designs.
The socializing part feels like an edge case but I guess it depends if you are cooking to entertain or cooking for your daily food. The daily food only a small portion of the cooking requires closing up the kitchen.
- Most days when cooking PM2.5 doesn't exceed 5ppm.
- I accidentally burned some vegetable oil this week, and PM2.5 shot up to around 70ppm.
- I fried up pancetta a little too hot a few months ago, rendering the fat entirely, and both PM2.5 and PM10 went up to >999ppm.
My instinct is that it should be less toxic from vegetable oil, if it's just vaporised... past the smoke point maybe the chemistry changes enough to make it more toxic. The body has mechanisms to remove foreign matter from the lungs, but how easily and how much it clogs up your lymph nodes seems to depend on what it's made of.
Now if we're cooking with gas (as the east Germans use to say in the 80's), that generates quite some PM2.5 in an of itself.
Also, anyone cooking eggs without getting to the Maillard reaction (or for that matter, with oil instead of butter) should never again legally allowed to approach a frying pan :D
That said, I personally use the Breathe Airmonitor Plus [1] - I kept having issues with calibration with the temtop unit. Mostly decided on this one since it uses an NDIR sensor similar to my Aranet which I carry with me all the time.
0 - https://amzn.to/423AAaj
If I ran my stove for more than 15 min my carbon monoxide / fire alarm would go off.
Does your extractor fan vent to the outside, or just recirculate through a filter? In my experience, people often overestimate how much protection ventilation provides. It mostly dilutes contaminants rather than removing or isolating them. For example, with moderately hazardous compounds, a fume hood works fine under normal use, but in the event of a spill it can’t bring levels back down quickly enough to protect the operator. In that kind of situation, an isolator makes far more sense or adding PPE, though that can be burdensome.
What really surprised me is how high the values get from just a single pan. It makes me wonder what it’s like in a commercial kitchen with multiple pans at higher temperatures, especially if the extractor fan fails and there’s no time to shut down operations to fix it.
Do you have references to back this up that I could read? Assuming the same fan size, ventilation would act like a perfect filter and remove everything out of the room that the fan pushes, whereas a filter will allow some particles to pass and recirculate. Especially useless if it is those metal fiber filters that are in a range hood that just remove some grease.
A quick search brings up the CDC guidance, where they discuss air changes per hour for a room. This will be for HVAC units, which operate on a completely different magnitude of airflow compared to a kitchen extractor fan.
https://www.cdc.gov/infection-control/hcp/environmental-cont...
This also matches my experience in industrial applications, you only need a single failure point such as a spill or a large enough leak and ventilation alone is no longer enough to keep people safe. This is why it's worth considering a glove box/isolator. You could make the argument that a glove box can also leak and I'm starting to sound like a safety engineer. Anyway at home either will be fine with outside ventilation being superior if done right.
People forget your breathing in the exhaust of burning a fossil fuel.
If we had stoves with a source of gaseous or liquid oxygen, then the NOx emissions would be greatly reduced.
0. https://www.co2meter.com/blogs/news/co2-carbon-dioxide-detec...
1. https://en.wikipedia.org/wiki/Gas_chromatography%E2%80%93mas...
As a side effect, I now have a collection of very well seasoned cast iron.
I suggest frying some bacon and report back.
Man, I wish I had the confidence to just disregard science and research done by professionals.
If there should be a cohort that would be the canary in the coal mine, it would be professional chefs, who day-in and day-out cook for a living over several hours per day. Yet, I have not heard of any studies raising alarms for the profession.
Cheers
What i like about this device that they give a very precisce and clear physical definition of each metric and explain by what quantitative factors the metric is influenced.
incl. potential measurement error sources and ability's to reset sensors.
Definitely recommend this over other air quality devices that try to simplify all the measurements into good/bad..
(Note: Just a happy user no affiliation whatsoever with the company)
Was it one of those useless microwave ones?
Where the device is relative to the pan and fan would clearly matter. It should be across the room to get a better estimate of the net effect. Not right next to the pan.
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