Spontaneous human combustion (SHC) is the burning of a person's body without the apparent presence of an external source of ignition. While the cause of such combustion remained for many years a complete mystery it is now generally accepted that the most probable reason for the appearance of SHC seems to be a non-spontaneous "wick effect" fire. The wick effect is discussed below.

Characteristics

There are many characteristics that together distinguish SHC from other forms of fire.

• Some cases seem to generate spontaneously without any observable source of ignition.
• The fire is usually localized to the body of the victim. Furniture and appliances near the victim are usually left untouched by the fire. Little or no damage is done to the vicinity of the victim.
• The body of the victim is usually more severely burned than in a normal house fire. The burns are, however, not distributed evenly across the body. The torso of the victim is usually very severely damaged, sometimes reduced to ashes, but the extremities of the victims are usually left untouched by the fire.
• Most cases of SHC occur indoors.
• Appliances (e.g., televisions) located on top of cupboards can be damaged.
• Victims are often female.
• Victims are often overweight.
• Most victims are also said to be alcoholic.
• There are never credible eyewitnesses of the actual combustion process

Complications

Being a large proportion water, the human body does not burn very well. However, in many cases of SHC, victims' bodies were reduced to cinders. To render the body to such a state requires temperatures of more than 1700 °C (3000 °F). Even in modern crematoria, which have temperatures around 1100 °C (2000 °F), the bones cannot be broken down completely and have to be ground into smaller pieces.

Many murderers have tried to burn their victims (in fact, many have attempted to cover up their crimes by SHC). However, once the accelerant (a chemical, typically a flammable liquid, used to speed ignition of a fire) is depleted, the victim will stop burning. This is true in the case of Adolf Hitler, whose body was burned after he committed suicide. However, his body was still easily identifiable even though more than 20 litres of fuel were used. Moreover, forensic investigation reveals no use of accelerants in suspected SHC cases.

So on the one hand, a normal fire would have had to be extraordinarily intense to have the observed effect on the victim, but on the other, the very limited damage to the surroundings contradicts this.

Theories

Of course, as with any apparently anomalous phenomenon, there are a number of theories that attempt to explain how SHC happens. One has a scientific basis; most do not. The scientific explanation (with minor variations) is this:

• The victim dies suddenly, e.g. from a heart attack, or loses consciousness or mobility from excessive drinking.
• A cigarette or some other source of flame ignites the victim's clothing which starts to burn, possibly fuelled by spill of distilled beverages, and kills the victim if he or she is not dead already.
• The "Wick" effect occurs (see below)

There are numerous non- or pseudoscientific theories.

The "wick" effect

The wick effect theory essentially says that a person is burned through his/her own fats after being ignited, accidentally or otherwise. The clothed human body acts like an 'inside-out' candle: the human fat (the fuel source) is inside and the clothing of the victim (the wick) is outside. Hence there is a continuous supply of fuel, in the form of fat that melts and drips to the victim's clothing. Fat contains a large amount of energy due to the presence of long hydrophobic chains.

Experiment

Using a dead pig wrapped in a blanket and placed in a mocked-up room, the BBC set out to prove the 'wick' theory in its science television show "QED". A small amount of petrol was poured on the blanket as an accelerant. After igniting the petrol, the researchers left it to burn by itself. The temperature of the fire was regularly recorded and it was only around 800 °C (1472 °F). As the fire burned through the pig's skin, the fire melted the pig's subcutaneous fats, which flowed onto the blanket. Bone marrow, which also contains a high amount of fats, also contributed to the burning. The surrounding furniture was not burned although a television placed above a cupboard had its plastic cover melted. The fire had to be manually extinguished after seven hours. Most of the pig's body had been burned to ashes.

From the experiment, the BBC researchers explained the following characteristics of SHC:

• The fires were highly localized. The flames of the fire were less than 500 millimetres high, therefore the fire usually did not spread to furniture in the vicinity.
• The body was very severely burned. The fire, although not very hot comparatively, can burn for a long period of time, as shown by the experiment. It is further fuelled by the body fat of the victim, which explains why the body can burn for such a long time.
• The furniture located above the cupboards burned. The fire continuously heated the air and produced a convection current. Hot air rose and caused the plastics in the television set to melt.

Use in fiction

Spontaneous human combustion is occasionally used in works of fiction. Charles Dickens used spontaneous human combustion as a plot device in his novel Bleak House (1853), which added considerably to interest in the subject. The television series Picket Fences featured an episode in which a recurring character died in this manner. The wick experiment was depicted in the television show CSI: Crime Scene Investigation in the episode "Face Lift". The film This Is Spinal Tap includes several references to spontaneous human combustion, as two of the ficticious band's drummers, in the band's words, "exploded on stage."

The film Spontaneous Combustion (1990) starring Brad Dourif references many facts that have been reported in cases of Spontaneous Human Combustion. For reasons pertaining to the plot, the cause of the phenomena in the film is attributed to radiation poisoning.

In South Park, season 3, episode 2, which is named "Spontaneous Combustion", some of the towns citizens die due to spontaneous combustion as a result of holding their farts too long.

Known cases

• Mrs Mary Hardy Reeser, aka The Cinder Lady
• Beatrice Oczki
• George I. Mott
• Alan J. Hinkle

See also

• Anomalous phenomena
• combustion

External links

• CSICOP article on spontaneous human combustion
• Spontaneous Human Combustion at the Skeptic's Dictionary
• A BBC article describing the experiment
• Article on causes of spontaneous human combustion including history