The Ejection Reduction Possibilities of Glass-Plastic Glazing

Ejection is a major problem in motor vehicle safety, with some 43,000 people per year being ejected from passenger cars, with some 6000 of these killed. About half of these people killed are ejected through glazing areas. The November, 1983, amendment of Federal Motor Vehicle Safety Standard 205 now allows the use of glass-plastic glazing anywhere in a motor vehicle. Our study has explored the “safety net” implications of glass-plastic glazing, produced by Saint-Gobain Vitrage, 3M, and DuPont for the anti-laceration implications but tested in our study for reducing ejections by controlled deformation after the glass layer or layers break. The inner plastic layers holds the broken pieces of a tempered side glazing together enough to reduce adult head partial ejection in side impacts, with the plastic layer trimmed to the glazing edges. By extending the plastic layer and securing it to the window channels, a 44 pound child moving at 20 mph toward the window may be stopped without ejection, with severe but possibly tolerable neck loads. Plastic layers which allow a greater deformation without failure appear desirable, to give glass-plastic glazing both a reduced laceration and a designed reduced ejection capability.

This paper presents the views of the authors and not necessarily those of the National Highway Traffic Safety Administration (NHTSA).