Fan Death is "the belief that if someone is sleeping in a sealed room (windows and doors are closed) with an electric fan on, they could die." The theory is that either hypothermia will get you, or the fan breeze will somehow form a vacuum around your mouth and suffocate you. Apparently many people in Korea believe this is true. Or at least, this is what Robin, the creator of fandeath.net, has concluded after living in Korea for five years. He writes:

When I first heard about fan death, I discussed it with my Korean friends and students. I was the foreign skeptic and they were the loyal natives. I was shocked at how powerful their belief was and at the lack of critical thinking about the issue. All you have to do is bring up the issue of fan death with a Korean and it would be difficult to get them to accept the fact that fan death might not be true. Especially when talking to a foreigner, they are more likely to defend their cultural belief than question it. So, unable to have a semi-neutral discussion, I turned to the internet. After checking the internet for more information about fan death, I became greatly frustrated. I could not find any detailed information about fan death. So, I decided to make this site to encourage others to tell their stories and share their knowledge about the issue.

Robin's site includes info about some other unusual Korean beliefs, such as tongue- cutting, which is the theory that if you cut the frenulum (the tissue linking the tongue to the floor of the mouth) "your tongue will be more flexible and be able to pronounce those difficult English sounds." Robin says that for this reason tongue surgery is quite popular in Korea.