Korean Fan Death
If you buy a stand, desktop or ceiling fan in Korea, it will almost certainly be equipped with a timer function to ensure it is not left running all night, despite the fact that in the summer temperatures can often exceed 30 deg C. There is a very real widespread belief that leaving a fan on in a closed bedroom overnight will kill you. Fans come with warnings to leave doors or windows open to ensure air is circulated and even the Korea Consumer Protection Board advises that “Doors must be left open when sleeping with the electric fan or air conditioner turned on."
The Korean media refers to “fan deaths,” every time they report on an otherwise healthy-appearing individual being found dead in his or her bed with a fan still spinning nearby. Stories like this propagate the widespread myth that fans are the cause and help fuel a very cultural superstition. The origins of the belief are unclear, there is a reference going back to the 1920's and some conspiracy theorists posit that the Korean Govt spread the rumour in the 1970's during an energy crisis.
Despite various hypotheses as to why fans can cause the deaths of humans - hypothermia or hyperthermia, excess dust stirred up from fans, excess CO2 from a closed room, or the common belief, suffocation - there is no actual evidence that running a fan overnight in closed room can kill someone. As to what does cause these mysterious deaths? The smart money is on previously undiagnosed heart problems or drug or alcohol abuse.The give away is that no other country seems to suffer similar waves of mysterious deaths attributed to fans.