THERMAL injury can be induced slowly or rapidly, depending on the intensity of the source. In peacetime, most burns result from exposure to low temperatures acting over a relatively long time; thus burns from hot water or steam are inflicted at temperatures ranging from 60 to 120 C. over periods of approximately a minute down to only a few seconds. Secondary burns from actual flame are usually deep because the temperature is high (300 to 400 C.) and in most instances the exposure time has been at least several seconds.
In modern warfare when certain high explosives burst within a confined space, as on naval vessels, and especially with the explosion of atomic bombs, temperatures of exceedingly high order are achieved, so that a new type of thermal injury, the "flash burn," is made possible. An atomic bomb explosion releases enormous quantities of energy as blast, radiation (gamma and neutron)
EVANS EI. TREATMENT OF HIGH INTENSITY BURNS. AMA Arch Surg. 1951;62(3):335-349. doi:10.1001/archsurg.1951.01250030341003