Predictive criteria for burns from brief thermal exposures.

Burns are a major cause of injury and death within the civilian and military communities. By accurately predicting the effects of brief thermal exposures, hazardous occupational situations can be identified and preventive devices and procedures can be developed. It is difficult to quantify heat transfer into skin, and calorimetry appears the best measurement method. Approximately 16.4 J/cm2 of heat transfer are necessary to cause second-degree burns. A free air temperature measurement method of predicting burns is less accurate, although, for brief exposures, a time-temperature integral of 1315 degrees C-second (2400 degrees F-second) above body temperature correlates with heat transfer causing second-degree burns. Both of these criteria apply to bare skin. When skin is covered with most types of clothing, a thermal protection factor of 2.5 (approximately 24.4 J/cm2) can be assumed.