Why does spontaneous combustion in humans seem to  occur near the head and not near the arse?
337445
Because people who believe in spontaneous human combustion have more flammable gas in their heads than in their ****.
866470
Lightning is the usual natural culprit.\n\nA lot of times it is human caused.  Either by purposeful arson or accident -- tossed cigarette, unextinguished camp fire, a controlled burn that got out of control, etc.
495646
Virtually nil, almost complete combustion occurs.
649680
Your body burns fuel to get the energy it needs to function. Just like any other combustion process, this generates heat. Since metabolism happens constantly, your body constantly generates heat.\n\nIn order to keep a constant temperature, your body has to balance heat production against heat loss. It turns out that this is easiest when the air temperature is less than your body temperature, since you will lose excess heat to the air. That's why around 75F (25C) tends to be comfortable for most people.\n\nIf the air temperature is the same as body temperature, you can only loose metablic heat through the evaporative cooling provided by sweating. This isn't as effective a process, so temperatures near body temperature aren't generally comfortable. \n\nIn fact, if the temperature is enough hotter than body temperature, sweating is no longer sufficient to maintain your internal temperature. As a result, the heat quickly becomes fatal.
756704
well i guess it would be anything under the bloods boiling point which is approx. 0.158 degrees centigrade. but of course it might still burn..i myself like hot water so i've bathed in water that had smoke rising from it and my skin turned red...is that hot or what! lol
437369
spontaneous human combustion\nhttp://en.wikipedia.org/wiki/Spontaneous_human_combustion
557833
Pure bunk. .Much like aliens ,never observed in real time . Post event finds a severly burnt corpse but fire started by smoking etc. ,then ignition of body's fat reserves causes an intense , but local fire until fat gone ,then fire dies out .The Nazis burnt their victims this way when they  built a small fire ,added corpses ,and then when fat melted it sustained the flames
220220
I never thought about it before this question, but it seems to have a lot of evidence in favor of it - temperatures high enough to reduce bones to ash, but often not destroy the legs of the victim.  This type of heat is not even generated by crematoriums, let alone dropped cigarettes.  according to wikipedia, its is a myth that SHC victims have set themselves on fire with a dropped cigarette.  Check out this article on it...
131039
Alcohol has a low flash point and burns with a near invisible flame.  It would be easy to start an uncontrolled flame that would be difficult to see.  All of which could lead to disasterous results.
359525
Take a look at the pyrotechnics chapter of this side.\n\nhttp://www.vk2zay.net/\n\nCareful: it is neither simple nor without danger.
863599
I'm a doctor, specifically a surgeon, but I never learned anything about this in my medical training.  However I'm also a rock climber and mountaineer of long standing and I was taught specific things about survival over many years by supposed experts.  Unlike the data that I use to support surgical decision making, where I review the science directly, I have not reviewed the science directly on this.  I do know this much, however: the method by which the conclusion is reached involves filming athletes with an infrared camera while they exercise.  \n\nI was quoted 30% of heat is lost through the head.  Not 80%.  80% would be silly.  30% is already a LOT if you consider that it represents nearly a third of your heat loss, for a body part that represents significantly less than 10% of your total body surface area.  The reason that this occurs (sadly enough) is NOT because of the brain.  Well... maybe in my case it's because of my incredibly powerful brain... but for the rest of you, its the SCALP.  :)\n\nThe scalp is enormously vascular.  Where a foot long gash in the skin of the thigh or back would be painful, it wouldn't be life threatening.  A foot long gash through the scalp, on the other hand, can absolutely lead to fatal bleeding.  I have seen people die like this, both in the mountains and in the city.\n\nThe heat loss through the head comes from the extremely efficient heat exchange between the scalp and the surrounding air.  The scalp has EVOLVED to be a radiator just like the ears on an elephant.\n\nAt altitude, temperature management can be a lot of work.  The principle is to retain warmth but not moisture.  There's nothing worse than being sticky sweaty AND cold.  A warm hat which breathes well, and which can cover the ears is essential.  The key is to put it on BEFORE you get cold.\n\nI hope that helps.
1099084
This sort of thing *can* be caused by exposure to synthetic chemicals, especially cleaning products, pesticides, and even fragrances. Cigarette smoke is the worst one for me. Some of us don't break these things down quickly enough and they build up in the body, which can create all sorts of problems.\n\nNutrition can play a part as well.\n\nTry searching under 'chemical injury' and see if it makes sense to you.
1126874
Your confusion lies in the sentence "How can such an intense heat not spread so far that it combusts the entire room as well?"  You are presuming an intense heat for some reason.  In my mind, the fact that nothing else burns means the heat was NOT intense. \n\nThe best hypothesis for this phenomenon is that the fat in the body melts and flows into a substance that works like a wick, such as clothing or upholstery.  The fire burns rather slowly and tamely so nearby temperatures don't increase enough to flash combust anything. This is just like the fire in a candle wick not burning the parts of the wick that are just below the flame, or a candle burning down to nothing without significantly heating up whatever it was sitting on. \n\nThe fat hypothesis explains why the head and limbs and associated clothes are unburned. \n\nYou could do a simple experiment.  Take a nice slab (not slices) of bacon and a long needle and thread a nice thick piece of cotton yarn through a fatty section. Warm the bacon to body temperature (maybe in a microwave on low or a warm oil bath). Put the bacon on a pan or metal outside. Maybe stick some rags or newspaper around the bacon, but not in contact to simulate "the rest of the room" Light the yarn that is sticking out. Shield the whole set up from wind so you don't have flaming pieces of wick flaking off and setting dry grass in your neighbor's yard on fire.\n\nI bet all the fat burns away over a period of many hours, leaving behind fairly uncooked meat, and unignited rags.\n\nYou might try repeating the experiment with a strip of cloth just sitting on top of the bacon. Again, the bacon has to be warm enough for some of the fat to flow. Maybe a large enough cloth will cook the whole slab, but I bet it still takes hours and the area around it doesn't get super hot.
771844
A\n\nVolcanic explosions such as St. Helen's are cause by super heat gases.  Often Steam.
245313
It's for the same reason that a building can burn up or burn down, or that inflammable means the same thing as flammable, or that some people's nose smells and feet run while other people's nose runs and feet smell - the English language is wacky!
49764
after you burn its suppose to do it automaticly.\nmine does.
1146718
OH CAN IT EVER. It's call blue-flaming or torqing. You lay on you back and throw your legs back over your head as far as you can. Hold a lighter (not a match) near the butt-opening. If you get too close you create some risk. Build up a doozy and let 'er rip while the lighter is going. You have to exhaust the whole thing, or else you risk bringing some of the fire back inside of you while your butt-opening is still, well, open. So push it all out. Some of the flames can get huge. Just watch out for the "banana torq". It wraps around and burns bad things.