Korean Fan Death

An urban legend in Korea states that running an electric fan at night can kill you.

by Brian Dunning

Filed under Health, Urban Legends

Skeptoid #287
December 6, 2011
Podcast transcript | Listen | Subscribe

Korean fan death
Fan death warning label
(Public domain image)

Today we're going to point the skeptical eye at a traditional belief from Korea, one at which many Westerners merely scoff. Many Koreans believe that sleeping in a room with an electric fan running is potentially lethal, even to the point that many Korean doctors and safety agencies formally warn against doing so. Scientists outside of Korea, however, easily dismiss the deaths as misdiagnoses of other conditions, and handily debunk the proposed mechanisms for the danger as implausible. But some Koreans have countered that there must be some explanation unique to Korea or Koreans: something to do with physiology, geography, or even their particular electric fans. Could Koreans be right that there is something more to this urban legend than mere tradition and confirmation bias?

Korean fan death isn't very old; not even going back as far as the use of electric fans in the country. The first electricity was installed at Gyeongbok Palace in 1887, just a few years after Schuyler Wheeler made the first two-bladed electric fans commercially available. By 1900, companies like Toshiba were manufacturing and selling electric fans throughout Asia. Despite nearly a century of history of usage without incident, in the 1970s the Korean media suddenly began reporting cases of fan death. They happened in the summer, in a closed room, and usually involved an elderly person sleeping alone, with an electric fan running in the room. In the morning, the victim would be found dead, with the only evident cause of death being the electric fan still sitting there, blowing its supposedly lethal breeze.

The situation today is that government safety agencies warn that fans must be used safely. The Korea Consumer Protection Board analyzed reports of heat-related injuries during the summer months for the three years prior to 2006, and made recommendations to address the five most often recurring dangers, with the first on the list being that doors should be left open when using electric fans or air conditioning.

If bodies are exposed to electric fans or air conditioners for too long, it causes bodies to lose water and hypothermia. If directly in contact with a fan, this could lead to death from increase of carbon dioxide saturation concentration and decrease of oxygen concentration. The risks are higher for the elderly and patients with respiratory problems.

From 2003-2005, a total of 20 cases were reported through the CISS involving asphyxiations caused by leaving electric fans and air conditioners on while sleeping. To prevent asphyxiation, timers should be set, wind direction should be rotated and doors should be left open.

Other government agencies give similar guidelines. As a result, many electric fans available in Korea today are equipped with an automatic timer feature, to make the fan turn itself off after a period of time for safety reasons. Fans from the Korean manufacturer Shinil Industrial bear a warning label that states "This product may cause suffocation or hypothermia". Such fans have a little warning sticker, a red circle with a yellow center, showing a body laying beside an electric fan.

The obvious questions to ask are how and why does this happen? But the important rule of thumb we learn to remember here is that the first question we should ask when investigating a strange phenomenon is does it actually happen at all? Obviously people do die in Korea, and some of them have fans running at the time. Whether the fan is causing the death is a question for the Korean coroners; and whether there's a plausible mechanism for such a death is a question for science. Let's take a quick look at the proposed explanations.

When we do this, we encounter our first red flag. Proposed explanations for Korean fan death are all over the map. There is no accepted scientific explanation. The most common is asphyxiation, caused by wind currents. Hypothermia is the second strongest contender, caused by the fan evaporating enough sweat off the victim's skin to wick away enough heat to kill them. But Korea's temperate climate is wet year round, especially during its summer monsoon season. The summers are hot and wet, and the winters are cold and comparatively dry. Fan death is a summer phenomenon; it's hot and wet. Are people really dying of hypothermia in such conditions? It is possible, if a stretch, if the fan's current is steady and dry enough. But fans don't dry the air or change its temperature; they merely circulate it.

Some posit really far-out explanations based on purely bad science. Some think the fan blades chop the oxygen molecules in half, rendering them useless or even poisonous; others believe that electric fans use up oxygen and produce carbon dioxide.

And, as with many urban legends, there's even a conspiracy theory that's been proposed to explain fears of fan death. When the stories first appeared in the 1970s, it was during a time when energy usage was sharply on the rise, and the Korean government thought up and spread the rumor to scare people into turning off their fans at night and saving energy. But like so many unproven conspiracy theories, this one has a pretty large hole in its logic. Energy usage during the summer is greatest during the day; and if the government was going to invent a rumor designed to reduce consumption, it would have made more sense to get people to turn something off during the day, like air conditioning or lights.

At least one Western expert has endorsed the theory that it is indeed the effect of the fan that kills. Dr. Laurence Kalkstein at the University of Miami is a climatologist and biometeorologist, studying the effects of weather on plants and animals including humans. At a conference in Korea, he explained that a fan blowing on an elderly person sleeping in a hot room would actually dehydrate the skin, causing death from respiratory distress. Even though the air blown onto the victim is as humid as a Korean monsoon, it should still carry away some amount of sweat from the skin, causing dehydration. So far as I've been able to find, Kalkstein has not examined any victims of fan death, so his suggested explanation remains unconfirmed.

However, there are doctors who have examined fan death victims. In 2007, Dr. John Linton who had autopsied several such people, told the International Herald Tribune:

There are several things that could be causing the fan deaths, things like pulmonary embolisms, cerebrovascular accidents or arrhythmia. There is little scientific evidence to support that a fan alone can kill you if you are using it in a sealed room. Although it is a common belief among Koreans, there are other explainable reasons for why these deaths are happening.

Dr. Lee Yoon Song told the Korea Times in 2006:

Korean reporters are constantly writing inaccurate articles about death by fan, describing these deaths as being caused by the fan. That's why it seems that fan deaths only happen in Korea, when in reality these types of deaths are quite rare. They should have reported the victim's original defects such as heart or lung disease, which are the main cause of death in these cases.

Tip Skeptoid $2/mo $5/mo $10/mo One time

But these dissenting opinions are in the minority. Most fan death victims examined by Korean doctors are given a cause of death of asphyxiation caused by the fan. Two professors of emergency medicine at Seoul's Samsung Medical Center agree that when a fan blows on your face, air currents develop that reduce the atmospheric pressure in front of your face by as much as 20%, causing a similar drop in oxygen availability. The victim then dies from the lack of oxygen. This is the prevailing view among Korean doctors who accept the fan death diagnosis.

The view is also wildly implausible, from any number of basic science perspectives. First, we don't observe people keeling over dead on mildly breezy days, even if they're sitting on a beach facing into the breeze for a long time. Second, we have no cases of brain damage from asphyxiation that was not quite sufficient to kill, which should be far more prevalent if this were indeed happening. Third, wind striking you in the face does not reduce the pressure at the front of your head; it increases it. Fourth, 20% is a huge pressure differential. 15 kph of wind would create around 55 grams of pressure on the average head, which is less than 1% of 1% more than normal atmospheric pressure. The Samsung doctors' 20% drop in pressure on one side of your head would require in the neighborhood of 100 kilograms of force at sea level, which would require a wind speed of at least 650 kph. So if you're using an F-18 fighter jet engine for a fan, it starts to look plausible.

So how do we properly analyze the phenomenon of Korean Fan Death? If we follow a truly skeptical process, what do we come up with? We've looked at the data and found that there are, indeed, plenty of people who have been found dead near a fan and had their deaths classified as fan death. But we also have good reasons to suspect that those causes of death were misdiagnosed: there are simply no plausible mechanisms for the breeze from a fan to be lethally dangerous. There was no significant difference in fan design introduced around the time the deaths began to be reported, and no differences between Korean fans and those in the rest of the world. There is nothing unique to Korea's geography (that we know of) that would explain why such a thing happens only there, and there aren't really any comparable cases of unique geography elsewhere in the world making certain technologies dangerous. Koreans outside of Korea don't seem to have any trouble with fans, and there is no known difference in Korean anatomy that would make them especially susceptible. Truly, all the possible factors that would make fan death a uniquely Korean phenomenon fall apart under scrutiny.

However, there's at least one remaining possibility that can explain what's being reported, and it doesn't require any new discoveries about anatomy or fans, or any special conditions. The simple fact is that we absolutely expect to see a correlation between summer deaths and fan usage. When it's hot and muggy in the summer, people are going to be running their fans; and when high-risk elderly people happen to die from whatever heat-related cause, it's perfectly likely that a running fan will be found nearby. The perception of a causal relationship between the two will be reinforced every time it's confirmed by another such body being found. This simple confusion between correlation and causation adequately explains all twenty diagnoses investigated by the Korea Consumer Protection Board, and it explains the convictions of the doctors, the fan manufacturers, and the safety boards.

So we never really get past our original question: Whether fan death has ever actually happened. It may have, most likely via hypothermia, but it would have to be in a colder, drier climate, and would be evenly distributed throughout such regions of the world. But so far as the existence of a specific Korean fan death phenomenon, the skeptical mind concludes no, there is no good evidence for such a thing's existence.

Brian Dunning

© 2011 Skeptoid Media Copyright information

References & Further Reading

Editors. "Why Do Koreans Think Electric Fans Will Kill Them?" Esquire. Hearst Communications, Inc., 22 Jan. 2009. Web. 1 Dec. 2011. <http://www.esquire.com/style/answer-fella/korean-fan-death-0209>

Editors. "The Truth of Fan Death?" Associated Press. 16 Jul. 2008, Newspaper.

Mikkelson, B. "Fan Death." Snopes.com. Barbara and David P. Mikkelson, 6 Jul. 2011. Web. 3 Dec. 2011. <http://www.snopes.com/medical/freakish/fandeath.asp>

Office of Public Relations. Beware of Summer Hazards! Seoul: Korea Consumer Protection Board, 2006.

Shin-who, K. "Do Electric Fans Cause Death?" Korea Times. 10 Sep. 2006, Newspaper.

Surridge, G. "Newspapers fan belief in urban myth." International Herald Tribune. 10 Jan. 2007, Newspaper.

Reference this article:
Dunning, B. "Korean Fan Death." Skeptoid Podcast. Skeptoid Media, 6 Dec 2011. Web. 10 Oct 2015. <http://skeptoid.com/episodes/4287>


Next up!!

Death by light bulb, because they found people who had died while the lights were on.


Death by oxygen! People were breathing oxygen when they died!!!

Im just kidding around, but if anything this article serves a much greater purpose than the "death by fan," junk.

It serves to show just how powerful the media is, how people can get so easily sucked into believing something so absurd because it was on TV.

We still see it happen here in the west today, with politics and more specifically (and dangerously) the constant bombardment of anti-Islam messages in the media.

Mathieu, Toronto
December 6, 2011 9:57am

A plausible way that a fan could be harmful to a person is when the ambient temperature is GREATER than body temperature (or some other critical point). Blowing warmer air onto a sleeping person could raise their body temperature to a lethal point. The person would suffer from Hyperthermia. A fan wouldn't actually directly kill the person but could theoretically speed up the process, much like a convection oven cooks faster than a standard oven. If the room is sealed and insulated well, the room temperature could continue to increase, especially of there are any heat sources in addition to the human body. This seems to jibe with the use of fans in the summer. Also, it would likely effect elderly moreso than heathy adults and young people. Just a thought. What do you think?

Frank T., Tampa
December 6, 2011 10:36am

This may not be just a Korean phenomenon. My father is from Portugal & grew up believing that sleeping with a fan on in the room is harmful, and still believes it -- though he can't always explain how or why it's dangerous, except to say it's "a bad idea." A few times, I've heard him say you can become paralyzed, but more often he just says it's not a good idea. I've told him I sleep with a fan on during hot months and so far I've woken up fine every time, but he still insists it's dangerous.

In his case, I suspect he believes there's something bad about moving air, because he also thinks you shouldn't stand in front of a working fan or a working air conditioner, even for a few seconds. Somehow air passing over you makes you sick? Ridiculous. No explanation for why people don't suddenly die or become paralyzed and fall over on windy days.

Dan, Massachusetts
December 6, 2011 10:50am

As to the fan decreasing pressure, I believe you are visualizing the situation incorrectly. If a person is lying in bed with a fan facing towards them the air moving over their face would reduce the air pressure over their face.

Kreig, Dufur
December 6, 2011 10:59am

The "convection oven" effect that Frank notes is also the theory that was proposed on the "Ask a Korean" blog a while back when he made a post on this particular topic.


Shane, US
December 6, 2011 11:00am

My mother and most of the elderly in my family still believe its very dangerous to sleep with plants or flowers in the room: At night, the plants/flowers use the oxygen and you'll suffocate. During the day it's OK because the plants "oxygenate the air".

It's especially dangerous if you're ill and - WITHIN MY LIVING MEMORY (I'm 44) - hospital ward sisters and nurses would remove all patients' flowers from their bedside at night, and bring them back in the morning. You can see nurses quietly performing this task in the background in some black and while films from the 40s and 50s.

I think it stemmed from a time when it was considered damaging to your health to sleep with a window open (coal smoke, smog?) and in a sealed room an invalid's bedside flowers could be deadly!

Kev, Berkshire, UK
December 6, 2011 11:18am

I'm Korean American, and lived in Korea for a while. I had never heard of this until I went there, and though it's of course absurd, with everyone giving a different explanation, most Koreans seem absolutely convinced this occurs.

It's a great cautionary case for explaining so many odd beliefs in the world. We search for patterns, and once we identify one, we ignore contradicting data, and remember only the supporting evidence. And how can you disprove a negative, that there is no fan death? If it occurs, it's so rare that you could never fully disprove it to a believer. Like autism and vaccines.

Note, though, that from what I remember, these deaths often ARE reported in the winter, and in fact the leading explanation for why it originated in the first place was the theory that charcoal heaters, which Koreans use to heat their homes in the wintertime, released carbon monoxide and other fumes, which were trapped in the closed room, and since Koreans used to all sleep on the floor, close to where the heaters are, they would occasionally suffocate. Though of course, why would you heat a room and run a fan at the same time? People do, though, to circulate the heat better - and it seemed a reasonable winter explanation.

Brian Kang, Long Beach, CA
December 6, 2011 11:44am

Korean Fan Death is what i am calling my (nonexistent) band.

juepucta, LA/CA/US
December 6, 2011 12:08pm

@Kev from Berkshire

You don't need to go that far back. About ten years ago, I saw the same thing and heard the same explanation from the nurses when my grandmother was in hospital.

Then again, nurses tend to aquire strange ways of thinking. I talked to a doctor once about rites and customs concerning death and he said that the nurses allways opend the windows of the room when someone died. Nobody could say why, just one older nurse said it was to let the soul of the deceased out.
Later I saw the same thing in a documentary on that topic. There too, most of the nurses doing it didn't even know why they opend the windows.

Felix Hummel, Regensburg, Germany
December 6, 2011 12:59pm

@juepucta: When your band tours Korea, I foresee a tragic headline, "Korean Fan Death fan fatally fanned in latest Korean Fan Death fan fan death."

I've met dozens of people in Europe and Latin America, who believe that being in a draft will make you sick. Often, these are the parents of my friends, who insist on closing all the windows in the house, car, train, bus, etc, whenever the air might move at more than a gentle breeze. This is very annoying when the weather is hot, the room stuffy, or when unpleasant odors, such as tobacco smoke, are strong. The explanation is simply, "a draft (moving air) can make you sick." It sounds like a belief in bad fairies to me, but it is quite widespread.

Derek, Santa Fe, NM
December 6, 2011 1:01pm

@juepecta: There's already a band called Fan Death.

Oissin, Hastings, UK.
December 6, 2011 2:31pm

Why the simple explanation, "they were old and in a sealed room on a hot day" doesn't have more traction is beyond me. Oh, it's not as bad as "in a sealed car on a hot day" - but the effect is much the same.

Heck, turning off the fans is probably *increasing* the death rate in those cases slightly!

David Johnson, Pasadena
December 6, 2011 2:52pm

It is possible to create a low pressure system by blowing air over an object. Take a straw and blow sideways across the opening and the liquid will rise up the straw. But.....and this is a big but....the pressure drop inside the lungs from the diaphram movement is many times more powerful than any home fan could produce.

Also the most plausible (I use this term for lack of a better one, not because I think it likely) explanation would not be hypothermia, but dehydration. A fan cools you by evaporating the moisture on your skin. If left long enough in a hot room with a fan and without replacing water, you could dehydrate. But if it was hot enough to dehydrate you to death with the fan going, you would also die from sweating and dehydration without the fan.

Brandon, Canada
December 6, 2011 3:52pm

There's one simple explanation to all of this that may not occur to Westerners. Authorities use "fan death" as a way of saving face and covering up an embarrassing or shameful death. Did he die of alcohol poisoning or drugs? No, he died from fans. You may wonder why doctors and politicians would go along with such a blatant lie. The reason is that if they died a shameful death, they would expect the same courtesy. It's a very different culture from the West. I've heard that many Koreans recognize "fan death" as just a euphemism, and not a legit cause of death, but I've never lived in Korea myself.

Jonathan, Tokyo, Japan
December 6, 2011 5:00pm

There's a possibly related cultural "disease" in Indonesia, called "masuk angen" ("wind entering" - not sure how to make that grammatical in English). The Indonesians will insist on traveling in buses and cars with the windows up, which is not a lot of fun considering the climate. People on scooters wear cloths over their mouths, not to protect from pollution, but from "masuk angen." Needless to say, electric fans are not popular, although they can be had. Air conditioning *is* popular, at least among the people who can afford it.

Stuart Frankel, New York
December 6, 2011 7:46pm

I can almost see a hypothermia/dehydration angle. Old people, if you've noticed, tend to forget to drink water: they loose low-water sensitivity. So a night of driving off what little remains through fanning, especially if it's not *too* humid (dryer air increases the dehydration faster), could possibly drive people who happened to have especially not had enough fluids that day over the threshold.

At that point, 'cooling' and any hypothermia effect would abruptly cease and the opposite would occur: rapid runaway hypER thermia. Heat stroke, heart failure, or whatever could rapidly ensue. Air cooling only works because the thin film of sweat carries off the latent heat of evaporation, water having a high specific heat index.

What size rooms are talking about? A healthy wattage brush-motor AC fan of bygone years when these rumours started might put out quite a bit of ozone, and fans may cool people locally, but ultimately they heat the room. A fan is actually a heating device.

So if you have a small room, a closed door, a hot day and night, plenty of ozone, a small heating unit, and an old person with an ozone sensitivity (I don't know if there is such a thing), who knows what might happen?

May it's just stats and correlation, though. I don't know.

danR, Vancouver/Canada
December 6, 2011 8:33pm

Compare this to the very real phenomenon of heater death due to carbon monoxide poisoning. If you didn't know about carbon monoxide, how would you tell if it's a real phenomenon? See if any of the arguments that debunk fan death would also debunk heater death.

P.S. When it happens to the Prime Minister of Georgia, one might suspect foul play.

Max, Boston, MA
December 6, 2011 10:15pm

So what you're saying is that the mild breeze when driving in the open car was what killed Kennedy? Now it all makes sense.

The question then becomes, did the government intentionally cause this mild breeze???

Stefan, Denmark
December 7, 2011 1:42am

@ Mathieu, Toronto

I have to refute part of the first comment, tho a bit off topic. yes, in USA maybe you get overhyped anti islam messages. the rest of the world, we just get the news, and its never short of islam (fundy radicalised etc) adherants killing others, mostly indiscriminately. There is a logical pathway in islam to do that stuff. It is particularly agile, more than the the other 2 monotheisms, at being able to be construed to inspire violence, in almost any situation. These ppl arent non islam adherants, not deviants, they are actually following it properly. The Quran tells us this, not fox(or USA) news. its all there. It became exquisitely clear to the world on 9/11. In fact 9/11 was the springboard for dawkins, harris, hitch, dennett, etc, and the popular rise of skepticism.

Jon, Auckland, NZ
December 7, 2011 2:05am

Y'know, this all reminds me of a cautionary anecdote in my basic statistics test, warning of the whole causation/correlation fallacy. It seems in a small mid-Western town, statistics showed that every year, when there was an increase in ice cream sales there was also an increase in street crime. Did consumption of ice cream cause people to go out and commit "street crime?" That was the first knee-jerk conclusion, until someone pointed out that this occurred every July and August.

Dedalus, Marietta GA
December 7, 2011 3:27am

@Dan, Massachusetts: I heard the same story growing up here in Israel - that sleeping with a fan at your face would paralyze your face (or something like that).

Jonathan, Haifa, Israel
December 7, 2011 4:53am

I'be been sleeping with a fan pointed at me for years. I had no idea I was fanning the flames of danger.

Alex Butler, San Francisco, CA
December 7, 2011 7:05am

@MAX, Boston,MA: Heater deaths from monoxide (not knowing that) are not comparable to fan. The one fact, that is common with heat dead is that it is not confined to one location, it happens all around world where heaters are on unlike fan deaths. Also argument of similarities is working: brease in face wont kill you, but running car engine in room would, as would any heavily burning thing in room.
Also the fan doesn't create unknown products, unlike fire if we wouldn't know that this is monoxide here. It would be clearly shown that smoke are consisted of sthing, while fan doesn't release anything

KLB, Kaunas
December 7, 2011 7:55am

@Brian Kang

I think you have to grow up in Korea to know the story. After I read this, I Skyped a Korean friend. At first (her English is not very good) she didn't understand what I was talking about. But as soon as she understood 'electric, fan, death', it was like:

Oh YES! They die, old people, young, everybody! Very serious!

I will still reserve skepticism on this one. Old fans, brush-motors-ozone, ozone sensitivity (there is such a thing, and it's amplified in the elderly), heat-generation from fan motor, dehydration/loss of sweating, closed small room, hot day.

It could indeed increase the stats on heat-death in the elderly over and above hot-day deaths.

Modern fans are brushless, no ozone; but yes, I would keep the door open, and make sure old folks are well hydrated. I happen to be one of those people who have lost or almost lost the ability to sweat (anhydrosis, I think it's called). When it goes over 80 F., nothing helps me but cold wet towels around the neck. Else my brain feels like it's about to fry. The metabolic rate needed to maintain 98.6 means the brain cannot keep the temperature below that level if waste heat cannot be thrown off.

I wouldn't want a hot motor blowing its warmed air on me on a hot day and night. The Koreans may be on to something (albeit a few cases in the vast majority of heat-deaths) that epidemiologists in other countries haven't considered.

danR, Vancouver/Canada
December 7, 2011 10:53am

Damn! I can just see hold-up men in Korea armed with battery-powered portable fans.

Personally I use fans year-round with open windows because I just don't like stagnant air - I could be a superhero in Seoul for that.

Rob Jase, New Britain, CT
December 7, 2011 12:28pm

My wife works for LG america and asked some of her co workers about "fan death". They all knew about it and believed in it. They gave the same reasons Brian covered.

She mentioned that I sleep with the door closed and the fan pointed right at my face all year long. There was concern for me.

Stan Brooks, Huntsville, Al
December 7, 2011 1:44pm

If having a fan running at night carried any risk of death at all, I'd have been gone a very long time ago. Living in steamy Florida for 10 years, I had a fan in almost every room in the house. The one in the master bedroom ran 24 hours a day. Thanks for covering this topic. I've heard about this years ago but never knew the details.

<a href="http://www.theinconvenienttruth.org"> The Inconvenient Truth

Guy McCardle, Linden, PA
December 8, 2011 4:14pm

Brian is clearly having to scrap the bottom of the barrel in his search for corporate paymasters. I mean, how much are korean fan makers really going to pay this guy?

Jimmy the Schnaze, Tokyo
December 8, 2011 6:02pm


If space heaters caused fires, then I'd have been gone a very long time ago. I'm still here, therefore space heaters can't cause fires, agree?

Max, Boston, MA
December 9, 2011 12:04am

I only see one other mention here of the sub-floor heating systems used in Korean homes, known as "ondol". This is basically a raised floor under which there is a fire source (typically large perforated charcoal blocks) which sends warm smoke throughout the spaces under the floors. When I was stationed in Korea 1979-81 there were many, many deaths due to carbon monoxide poisonings from these types of old heating systems. Any Korean homes lived in by US military personnel had to be inspected for problems with the ondol system prior to rental. Also, a window was required to be left open when the system was in use. As soon as I read about the "Korean fan deaths" I thought of this. Of course, there is supposedly a correlation with summer. It might be that some older Korean people have their heating system on even in summer. Also, Korea is not necessarily "warm and wet" all summer. Depends on location. Where I was it was hot in the summer, but not wet.

John Hairell, Maryland
December 9, 2011 12:46pm

My father once experienced fan-related trauma. It was a positive-pressure fan used by the fire department to increase the air pressure in homes, blowing the smoke out so the fire fighters could see (SCBAs are still required). He was demonstrating proper safety, his exact quote being "Never stick your finger in the fan like thi--someone get a mop and the first-aid kit."

I remember as a kid hanging out in the fire station, and the firemen (no sexism here--they all happened to be men) used that fan to keep cool in the summer (boys and their toys, you know how that goes). Ages ranged from 6 or 7 to 60 or 70, and this fan is well beyond anything anyone can use in the home, due to various laws and engineering concerns. Suspiciously, not a single one of us ever died from using the fan, and only my father was ever injured (that through direct contact). If anything is going to cause damage, a fan designed to create a pressure differential is going to be what does it--and nothing ever happened. I'd say that this at least demonstrates that fans alone aren't the cause, and I'd go so far as to say that those experiences rule out anything a fan alone can do as a mechanism.

The mechanism involved in space heater deaths is well-understood and well-demonstrated, on the other hand. I've used them to light fires before (ran out of matches, and grandpa got upset when I used his torch to light a fire on the farm).

Gregory, Alabama
December 9, 2011 1:27pm

In the episode, Brian offered the following explanation for how the Korean people might have first "discovered" the correlation between fan use and sudden death: that elderly people experience more heat-related deaths in the summer, when fans are more likely to be running.

That makes perfect sense. But I was having fun speculating about a mechanism by which the correlation between fans and sudden death might perhaps be a bit "stronger." Is it possible that fan usage is not just a marker of warm weather, but also a marker for the ABSENCE of central air conditioning? That is, that people who run fans at night are probably less likely to have houses equipped with AC? It this case, it you might expect to see more heat-related death is houses that have fans, simply because they actually might be hotter inside!

Anyway, really interesting episode. Hard to believe that so many Korean doctors subscribe to this idea.

AaronM, Durham, NC
December 9, 2011 9:24pm

There's very little information here about what actual evidence sounded the alarm about fan death. Did whole families die, as sometimes happens with carbon monoxide poisoning? Did only the family members who slept with a fan on die? Did autopsies show something unusual about these deaths? Did they indicate dehydration?

Max, Boston, MA
December 9, 2011 11:31pm

Great episode Brian, but you neglected to mention one hypothesis - that the fan turns your room into a "turbo oven" and kills you with Hypothermia, literally baking you alive!

Really, with this kind of slipshod research, how can we trust anything you offer? LOL


Dan, Woonsocket RI
December 10, 2011 11:25am

@Dan its "hypERthermia", not "hypOthermia" that you mean.

Really, with this kind of slipshod knowledge, how can we trust anything you offer?


Jon, Auckland, NZ
December 10, 2011 4:16pm

One mechanism that sounds plausible is ozone. A poorly constructed fan could produce ozone. In a closed room the concentration might get high enough to cause difficultly breathing which could be problematic for the elderly.

Jason, Sudbury,MA
December 13, 2011 4:46am

There was an episode of Radio Verda back in September 5, 2009, and it talked about this. The episode was titled "Kial koreoj timas ventumilojn?" They concluded in their podcast that it was an urban legend.

Mrs. S., Pacific Northwest
December 13, 2011 11:05pm

English for runaways:

* hypothermia
Abnormally low body temperature

* hyperthermia
Unusually high body temperature

Keep smiling. ;)

AL, Augsburg, Germany
December 14, 2011 4:34am

Having had fans blowing directly in my face every night (can't sleep without it really) for as long as I can remember, it's a good thing that it's not dangerous to do so.

John G., Minnesota
December 14, 2011 1:31pm

Jason - if fans were to produce ozone that caused deaths, you'd expect to see fan deaths distributed equally among the world's fan-using locations.

The giveaway really is that this claimed phenomena is so localized, clearly pointing to a cultural belief that has no actual truth behind it.

Further, fans producing ozone would be something that would be easily detectable and testable, and were this happening, there wouldn't be so many competing explanations for the claimed phenomena; it'd be trivially concluded that the ozone was the killer.

Jarno Lahtinen, Helsinki, Finland
December 15, 2011 6:41am

Did anyone check to see if the fan had spontaneously animated, forming a body from nearby furniture and walking over to the accompaniment of screeching violins, to chop the victim to pieces?
Well, I happen to think that the Freddy Krueger animating household objects to murder you in your sleep is perfectly plausible.
And, until you can disprove it, it has to be true.
(brought to you by Korean "science" and Occam's Hair Growth Formula)

Glenn Crawford, Toronto, ON
December 16, 2011 4:51am

i suppose the reverse of this would be heater death in Siberia (note to my Knowledge this does not exist either)if

eman ruoy, ytic
December 18, 2011 12:20am

Good article but...
You state that "fans don't dry the air or change its temperature; they merely circulate it." Actually electric fans do change the air's temperature. They increase it. So it could be that leaving a fan on in a small, closed room for long periods could aggravate normal hot weather health conditions but I doubt statistics would be much different in different places. So unless Korea has much smaller rooms, much less efficient fans, and some social bent to keep rooms sealed at night then I would agree with your conclusions.

Gord Goebel, Toronto, Ontario
December 19, 2011 6:23pm

.evoba ti tuoba detsop I .tsixe seod gninosiop edixonom nobrac ot eud htaed retaeH

Err, I mean heater death due to carbon monoxide poisoning does exist. I posted about it above.

Max, Boston, MA
December 20, 2011 12:45am

yeah um i was kind of makeing a joke :)

eman ruoy, ytic
December 20, 2011 3:45am

I suppose the Western version of this is the idea that if you go swimming straight after eating you WILL get a cramp and you WILL drown.

Holly, Stafford
December 22, 2011 3:31pm

I wish I toured Korea with my band to endure fan death..

two problems..
I cant endure the guys for longer than an afternoon and such;

I havent really got what anyone would call a band.

Yeah, I brought it on myself playing baritone because bass makes me puke after 15 minutes.

(I think its the sub harmonics having an effect on my subluxations).

CO death from heaters is demonstrable in fuel heaters world wide.

Its a bit like building collapse death, only because a fantastic proportion of humanity lives in mud brick in 2012.

That and thermite and flouride...

Nobody ever gets the secret..

Mud, Sin City, NSW, Oz
January 4, 2012 2:58am

When I lived in South Korea, I spent some time translating news articles to improve my Korean vocabulary and translation skills. One of the stories I encountered was shocking.

The story involved several college-aged young men who decided to commit mass suicide via fan death. They rented a "love motel" room, brought in several fans, and lay down to await their deaths.

Their plan was foiled when one of the men saw through the window the flashing lights of a patrolling police car. He opened the window and yelled for help, and all were rescued.

This story was reported as legitimate news. Every Korean I've asked about this really believes in fan death. Fans there come equipped with timers. Some Western friends who married Koreans tell me their spouses insist on using the timers just to be safe, although they claim not to believe in the legitimacy of fan death.

Shane, North Carolina
January 5, 2012 7:47am

i think it's closer in relation to spontaneous combustion.. a death where someone can't find the cause.. so they choose any idea they can come up with..

Peter, Australia
January 20, 2012 11:42pm

And I thought it was only Japanese that believed this. My wife is Japanese and is worried about me using the fan while I sleep. She even asked one of her friends (also Japanese) to confirm it to me. "Yes," she nodded gravely, "it will cause your body temperature to drop and it will kill you." Guess they never heard of the biological process of thermoregulation.

Paul, Oregon
January 31, 2012 5:18pm

Though various cultures do have myriad mythical health concerns, this is an odd one.

Comparing it to the western notion of not swimming after you've eaten is silly. While many of us heard that growing up, I think societal consensus is that is a "wive's tale." While some may believe it, there are no government warnings or special products designed to alleviate the problem, unlike the case of Korean fan death.

The comment about Japan is interesting. I lived there for two years, and never heard a word about fan death. The part of Kyushu I lived in had sweltering hot summers, and I know I'm not the only one who had my fan and air conditioner on full blast most nights.

Ben, New York
February 5, 2012 1:03am

I believe this was started by the government in the 70s, perhaps to try to reduce people's electricity consumption.

I can only think it persists either because of ignorance, or perhaps to use as a euphemistic cause of death if someone's drank/poisoned themself to death

Will, London
February 14, 2012 12:38am

I enjoyed the public domain picture so much, I used it as my Facebook profile photo...
The podcast was great as well.

Sara G., California
February 24, 2012 11:46am

I grew up in Japan and heard this from various people as well. It wasn't that running the fan all night was dangerous, but having it directed at your body all night could dehydrate you and potentially kill you. Air conditioning was ok, and fans directed above the sleeping body was ok. I think it stemmed from a few deaths of the elderly and the very young who died of dehydration over night. The deaths may have been unrelated to the fans (heatstroke, dehydration), but there were enough deaths that it caused concern.

S, Tokyo
February 28, 2012 12:59pm

Excellent article, but I noticed an error in your analysis:

"Third, wind striking you in the face does not reduce the pressure at the front of your head; it increases it. "

I'm pretty sure the decrease in pressure they are talking about would be due to Bernoulli's principle, which states that as the speed of a moving fluid increases, the pressure within that fluid decreases.

This is the same principle that creates lift on an airfoil. The air moving across the top of the airfoil is moving faster than the air at the bottom, causing an area of lower pressure above the airfoil. Likewise, in the case of a fan blowing air at a person's face, the air moving quickly past the person's nostrils would be noticeably lower in pressure than stagnant air.

You can try this yourself. If you place a rapidly blowing fan directly in front of your face, you should be able to sense a slight shortness of breath.

It is true that blowing air at a person's face would create pressure on the face due to the force of the air molecules hitting their skin, but unless you are actually blowing air up into the nostrils, the lungs would still experience a pressure drop due to Bernoulli's principle.

I still don't think this accounts for enough of a drop to cause asphyxiation, and like you stated, there are other reasons why it doesn't make much medical sense. But in the interest of accuracy and science, I thought it was important to point out that the part about the pressure drop is in fact true.

Joseph D., Portland, OR.
March 9, 2012 3:10am

What I've heard is that one of the blades can dislodge and kill you. (Another Korean story)

Chriss, England
March 26, 2012 1:20pm

I resent one of mathematics greatest being disabused in such a manner.

Joseph, its one of those posits that is easily tested without resorting to a misinterpretation of laminar/turbulent flow.

Now as to dislodging blades..has anyone here ever pulled a fan apart? Has anyone here actually thought of the difference in forces over vectors with respect to say...a propellor?

That's two in the bin, never to be recycled..

Senor Pastore Fanbelt Mud, Sin City, NSW, Oz
March 26, 2012 9:14pm

I would have thought the answer quite simple.

Using a fan in a sealed room increases the temperature in that room.

Benjy, Phuket, Thailand
April 22, 2012 4:37am

Its the elephant we all miss when making analogies Benjy.

At least you are in a country when some elephants really are pink!

Mud (now overweight as well), out to pasture, NSW, in many gardens, Oz
July 12, 2012 5:03am

I have to go for the "fan blades chopping the O2 molecules into single atoms" theory as the most plausible.

The fan is blowing onto the face of the sleeping person all night, who is now breathing in a high concentration of single oxygen atoms.

Thus a higher level of carbon monoxide ( CO ) than the normally low levels produced by metabolism is created in the body causing gradual poisoning overnight.

The door being closed compounds the problem, as the recirculated air now has not only a higher concentration of CO2 but also CO.

This may be survivable by younger robust individuals, particularly when the bedroom door is flung open in the morning just in time, but the elderly and retired are more vulnerable to this insidious danger.

Why it is only a Korean problem I have no firm theory, but I'm working on it.

I suspect that a memo sent to all Korean manufacturers of electric fans last month from the government health department may shed some light on the matter.

The memo carries a strict warning to manufacturers to make their fan blades less sharp around the edges, in order to minimise the oxygen molecule-chopping effect, especially at high speeds.

Macky, Auckland-by-the-Sea
July 16, 2012 2:30pm

So, Macky. Can you back up your claim with any evidence, or are you going to continue to believe that fan blades are capable of creating spontaneous nuclear fission?

Anonymous, Ohio
July 25, 2012 9:48pm

Well no, Anonymous, it's not nuclear fission because the atoms themselves haven't been split, as I understand it.

The atoms have only been separated from each other by over-sharp Korean-made fan blades turning at high speeds.

I could be wrong on this one though......

Metabolism produces levels of carbon dioxide, and I'm now wondering if something that is eaten by only Koreans produces more CO2 than normal, then coupled with forced air being blown into the face of the sleeper, causes asphyxiation.
Perhaps a large meal of this as-yet unidentified Korean food taken right before bedtime produces CO2 in quantities that are survivable by robust and younger persons, but not by the elderly, frail, and retired.

Macky, Auckland-by-the-Sea
July 26, 2012 1:02am

Macky, please stick to wiring peoples phones. Clearly you science impersonation of Oxygen molecules and oxygen ions was meant to be comedy but those north of the equator wouldnt get that.

Mind you, the comment on nuclear fission by Anonymous could have ruined your schtick had you not thrown in that great line about the relative you havent recognised until July 26, 2012.

Anonymous, you make a great straight man for these routines. Macky, in standards we used to have to polish knobs on a daily basis.

You are an example of commitment!

Could I refer you to an organic chemistry book so you can understand oxidation reactions? There is a fun line at the start of every paragraph in a chemistry text.

Mud, Sutho cricket ground, NSW, OZ
July 26, 2012 10:54pm

You're right, Mud. I only got two runs away before I was clean bowled at the Sutho cricket ground.

I rather hoped that a combined Australasian think-tank alliance would be formed, with increasingly brilliant theories posted in the fond hope that we may suddenly stumble on a solution for the Korean Fan Death problem.

Unfortunately that's been knocked on the head, now.

Ah well, back to the pavilion for a cuppa tea.

Macky out for two, Auckland
July 27, 2012 12:01am

Thankfully, yerv said it perfectly...as the kiwi side exempliarises.. its all ducks till a spin bowler bats!

Yer a clever person and some of the twists and turns you take are breath taking.

Enjoy Macky!

As to an Australian think tank?

We like it with fine wine and beer. Thank goodness we have our little brother New Zealand to supply us superb hop and spectacular sport.

If that was not enough to be proud of, New Zealand has superb science.

Antipodeans must mean progress...

Its just we have very weird vice chancellors and "equivalence" technical education.

Brian likes his think tank in a spa pool. Check skepticzone.

Clearly its a warm water predilection that those above the equator can afford on their energy policies!

See you soon!

Mud, Sutho cricket ground, NSW, OZ
July 27, 2012 12:27am

Dang, wish I had a Korean fan blowing me all night but I am not famous enough to have fans ;)

I can remember reading about this a while ago and thought it was all spoof or hoax, but no, they do believe it.

I would like to know where the origin came from, would make a great study as to the foundation and propagation of myth and lore.

The correlation and causation fallacy seems much in evidence, a lot of folks have died in hospital beds and in armchairs in their own home - ban them now !!

My sister died a few years ago and they never found out what killed her, just peacefully died in her sleep at 39. No booze, no drugs, no heart problems, she was fit and healthy and looking forward to a great life with her family and new child.

Sometimes people just die, maybe someday we will know all the answers as to why, but if sis had been Korean with a fan in her bedroom she would have been a fan death, I suspect.

Just goes to show that even today a whole country can believe in the 'truth' of nonsense.

David Healey, Maidenhead, UK
September 14, 2012 1:00pm

Haha, I can't believe he did this one. I lived in South Korea for 5 years as an English teacher. The first time I heard about it was when a teacher at another school in my town died. My boss told me about it and said it was the fan. My first though, "Oh, was there a fire?" Then my co-worker explained the whole thing to me and I had never been more confused in my life.
Later that summer when I bought a fan I noticed that the timer would buzz when it was set to stay on all the time. I had to open it up adjust the wiring, thus making me far more susceptible to the most likely cause of fire death, electrical fire.
Finally, fans can lead to death via hyperthermia, not hypothermia, in a closed room with a high enough temperature. The EPA explains it here http://www.epa.gov/hiri/about/pdf/EHEguide_final.pdf. However, the deaths tend to occur at night. So that is not happening either.

Leonard, Las Vegas
February 23, 2013 2:32pm

The thing is, the explanation by geographical or physiological idiosyncrasies do appeal to Koreans, who always like to think of themselves as special or even exceptional. Take my Korean wife, for example: she is convinced that child delivery is more dangerous for Asians (especially Koreans) than for Westerners, because Korean women are supposed to be more fragile. No mention here that Korean women have been delivering babies for millenia in far harsher conditions than today, without a particularly higher rate of death in childbirth. If her belief were true, then Koreans would have been extinguished long ago.

But Koreans have a kind of inferiority complex: they've been overshadowed for so long by China and Japan that they compensate today by overemphasizing their successes and their particularity. This is why many of them will buy into the fan death belief, and why the fact that it only happens in Korea doesn't disturb them.

Talking about this belief with Korean believers, I came across an explanation that resembles the oxygen-chopping blades one: the wind from the fan is MECHANICAL, which is bad, bad, bad, compared to the NATURAL wind which is nice and healthy and doesn't kill people because it's so sweet. Koreans are also big believers in "natural" products.

alfa8my, Seoul, Korea
March 29, 2013 2:43am

@Macky, Auckland-by-the-Sea

If fan blades cut oxygen molecules apart then we would be using them as scientific pieces of equipment. Not as household items used for comfort.

I can imagine the hydroponic and other plant industries would be very upset they have wasted thousands investing in CO2 technologies when all they need to do was turn on a fan.

But I do sense a bit of 'tongue in cheek' with your post. Maybe you have trolled me good.

John, Perth Western Australia
July 25, 2013 6:43pm

John, I've had to move away from the fan-blade O2-chopping theory, due to indecent exposure by a cricket player from the Sutho Cricket Ground in NSW who I am told goes in to bat without a protective cricketers' cup.

For a while I searched diligently for a Korean food which was not eaten by any other nationality, and which caused unbearable and fatal amounts of stomach gas when a fan was also running overnight in the bedroom. Just when I thought I had solved the problem, some aerial ping pong star from Melbourne crows up that he only eats Korean food in his diet, including what I had thought was the culprit of all the Korean fan deaths.
The aussie rules player also stated emphatically in the interview that he regularly uses Korean-brand fans while sleeping at night, and gave assurances to Carlton supporters that he was not in fact dead.

I've come to the conclusion that alfa8my basically has the answer.

Bad mechanical wind, but worsened by a wayward batch of Korean fans which were built to rotate clockwise in harmony with the southern hemisphere, and which were on their way to Sydney.
Something went wrong with the order, and the fans ended up back on the local Korean market being used where fans built for the northern hemisphere would normally be used.

This has enhanced the dangers of Mechanical wind rotating the wrong way through the room, and into the air passages of retirees and old surfers slumbering in the dark, particularly if they snore.

Macky, Auckland
July 26, 2013 2:23am

I don't know about fans, but it is a fact that space heaters in Japan can kill you. See the film "Battle Heater" for details.

Ben, Columbus, OH
March 3, 2014 8:02am

I came across the notion that having a fan in the bedroom is bad for your health when I lived in Syria in 2004. I got terribly ill (dysentery) but when the local doctor arrived the first thing he did was scold us for having a fan in the bedroom, that it could make us sick or even kill us.

"Oh great," I thought, "I have a voodoo doctor. I'm doomed."

Dave, Lexington, KY
October 23, 2014 3:33pm

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