Human Combustion

There have been at least 200 claimed instances of what is termed Spontaneous Human Combustion. However at least half of these can be accredited to external fires causing external burns to the body, severe enough to cause the death of the victim. Smoking materials of one form or another are probably the most prominent cause of ignition of the remainder, together with sparks from fires. The mechanisms by which these result in fires in or around humans, by which the body can be reduced, at least in the main, to a residue of white ash can be:

The ignition of upholstery, perhaps smouldering for a long period whilst burning the victim's skin.

The ignition of alcohol-laden breath, leading to flames burning the throat, trachea and even the stomach, depending on the amount consumed.

The smouldering of clothing, perhaps over an extended duration, whilst it instils severe burns on the skin.

The Wick Effect raising the temperature close to the skin,causing burns to penetrate the body and ignite the body fat, drawing out the pyrolysed products just like a candle wick.

There is no need to invent new sub-nuclear particles or novel chemistry. The existing physical mechanisms are sufficient, and can act either very rapidly or insidiously over many hours.

The supposed process of Spontaneous Human Combustion is a fantasy.