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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.

The facial laceration test has been proposed as an addition to the dummy injury criteria of Federal Motor Vehicle Safety Standard 208. To better understand laceration conditions as they actually occur, three road crashes of increasing severity, all involving facial laceration by the broken (cracked) windshield and one involving partial ejection, have been simulated physically and analytically. The physical simulations used vehicle test bucks, the Hybrid III head with the chamois facial coverings of the facial laceration test, and a piston - constrained Head Impactor. Computer simulations of the three crashes were also carried out using the CALSPAN 3D “CVS” and the 2D “DRISIM” computer programs. The computer simulations provide insight into the effective mass of the head and body on windshield contact, and the forces, velocities, and accelerations involved.

About one fourth of the occupant deaths in passenger cars in the United States involve either complete or partial ejection. Approximately one half of these ejections are through glazing areas. This paper presents research results which demonstrate the potential of glass-plastic glazing to significantly reduce ejections through motor vehicle windows. Four passenger car and four light truck and van rollover experimental crashes were conducted. All the vehicles had glass-plastic front side window glazing. One of these included the improved glazing with a movable encapsulated “offset T-edge” design. Two in addition had glass-plastic windshields. Even with glass breakage and window frame distortion, the glass-plastic glazings maintained their “safety net” ejection reduction function. Laboratory dummy drop and sled tests of the movable glass-plastic glazing side windows are reported.

We are seeking to test and adapt successful devices for child crash protection from outside the United States not now used here. Test results and possible problems are presented for a transverse infant bed, a toddler backward facing seat, and an older child booster seat with back and head supports (from Kilppan, Sweden), and the Australian “Sit-Safe” design, an inexpensive belt to go between the shoulder strap and the lap belt to insure that the shoulder belt does not touch the child's neck. We have also tested an inflated pad alternative to the upper back of the front seat bulge passive restraint of DeRampe (France) to reduce knee contact - leg straightening - body vaulting which contributes to ejection of unrestrained people from the back seat. And we are testing plastic coated side glass to explore extending the anti-lacerative glazing advance of Saint-Gobain Vitrage (France) to the even more significant potential reduction of ejection.

1983 ejection statistics are reviewed; half of the passenger car ejections, some 36,000 people of whom 5,346 died, are through glazing areas. Previous work has shown the remarkable strength of thin plastic coatings, developed for windshield anti-laceration applications, when applied to the inside of tempered glass side windows, in reducing ejection. In the present work, two tests were made, each with the NHTSA Moving Deformable Barrier (MDB) at 39 mph and all four wheels turned at 26 degrees, striking a stationary Volkswagen Rabbit in a perpendicular impact. The Alfred I. DuPont de Nemours Company provided the plastic coating on tempered glass side windows. The plastic layer extended beyond the sides and top of the glass to be wrapped around steel strips bolted to the window frame. On vehicle impact, the tempered glass broke, but the pieces were held in place by the plastic layer, which then deformed outward as a “safety net” with head contact.