Spontaneous combustion is a type of combustion which occurs by self heating (increase in temperature due to exothermic internal reactions), followed by thermal runaway (self heating which rapidly accelerates to high temperatures) and finally, ignition. Wikipedia, Spontaneous Combustion
Spontaneous human combustion (SHC) describes reported cases of the burning of a living (or very recently deceased) human body without an apparent external source of ignition. As of 1995, proponents claim that there have been about 200 cited cases worldwide over a period of around 300 years.
There are many hypotheses that attempt to explain human spontaneous combustion. These include several natural explanations as well as supernatural and biblical explanations.
Natural explanations include those:
1- Based on intestinal conversion of food into methane by methanogens which, when released through the pores of the skin, can catch fire when triggered by various sources (e.g., silk cloth generating static electricity).
2- Based on unknown or otherwise unobserved phenomena (e.g., that the production of abnormally concentrated gas or raised levels of blood alcohol might cause spontaneous ignition)
3- Relating to health and lifestyle factors (e.g. smoking, not consuming adequate levels of water, etc.)
4- That involve an external source of ignition (e.g., the victim was drunk and dropped a cigarette)
Objections to natural explanations typically refer to the degree of burning of the body with respect to its surroundings. According to proponents, one of the common markers of a case of SHC is that the body – or part of it – suffered an extraordinarily large degree of burning while the surroundings or the lower limbs remained comparatively undamaged. Wikipedia, Spontaneous human combustion
NOTES: In the photos of SHC there are no pools or streams where liquids have run off. This indicates the water in the body was also combusted or dissociated.
See Also
9.8 - Spontaneous Creation of Harmonic Series
15.14 - Dissociation Liberates Spontaneous Energy
combustion
Disintegration
Dispersion
Dissociation
Fire
Flame