Progress is described on the development of a trauma-indicating headform for assessment of localized and superficial head injury hazards. Using as a basis the facial and parietal bone impact tolerance values obtained in collaboration with Nahum, an anatomically shaped skull has been developed in which particular attention has been given to achieving humanlike fracture tolerances in the zygomatic and frontal regions.

Beginning with a polyester skullform cast from a human skull, a series of developmental steps is described which includes modifications to "idealize" geometrical symmetry, tailor the section thicknesses for average fracture force intensity in the principal regions, and select a skull structural composite material and overlying soft tissues for balance in fracture strength for both large area and localized impacts.

The frangible skull in its present state of development has been used as a research tool to indicate facial and frontal bone fracture. The accuracy with which these evaluations represent human bone fracture is not well established because of the limited biomechanical data base. As a more complete understanding of human skull fracture is developed and with further studies to control the material properties and structural geometry of the frangible head model, it may become a useful device for evaluating human skull fracture hazard in impact environments.