How long can a person survive in a fire?

Answer 1

The number one cause of death in most building fires is smoke inhalation. The actual reason for death in these cases is oxygen deprivation and toxicity (primarily from carbon monoxide), which in turn means that it can take up to five minutes for brain death to occur.

Death by burning generally can take quite a long time. The best information we have for this is history. Burning at the stake, a common form of execution in the past, typically could take thirty minutes or more (sometimes up to days depending on the intensity of the fire and wind conditions--blowing away toxic fumes such and carbon monoxide and carbon dioxide). Death in these cases was usually the result of shock, heatstroke, exsanguination (blood loss), the destruction of vital organs.