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The factors that influence airbag-induced upper-extremity injuries sustained by drivers were investigated in this study. Seven unembalmed human cadavers were used in nineteen direct-forearm-interaction static deployments. A single horizontal-tear-seam airbag module and two different inflators were used. Spacing between the instrumented forearm and the airbag module was varied from 10 cm to direct contact in some tests. Forearm-bone instrumentation included triaxial accelerometry, crack detection gages, and film targets. Internal airbag pressure was also measured. The observed injuries were largely transverse, oblique, and wedge fractures of the ulna or radius, or both, similar to those reported in field investigations. Tears of the elbow joint capsule were also found, both with and without fracture of the forearm.

An acceleration sled carrying living human subjects was used to measure the dynamic response of the head and neck to —G x impact acceleration. Seated volunteers with complete pelvic and upper torso restraint were subjected to increasing impact accelerations beginning at 2.7 g and increasing in 1 g increments. The volunteers were selected to encompass the 5th to 95th percentile distribution of sitting height according to a selected reference. Precision inertial transducers were used to determine the linear and angular acceleration of the head and the first thoracic vertebra. The inertial system consisted of a biaxial accelerometer and rate gyroscope on a bite-plate, a biaxial acceierometer over the bregma, and a biaxial acceierometer and rate gyroscope over the spinous process of the first thoracic vertebra. The transducers on the bite-plate and over the bregma were rigidly connected to one another.

Properties of the human neck which may influence a person's susceptibility to “whiplash” injury during lateral impact have been studied in 96 normal subjects. Subjects were chosen on the basis of age, sex, and stature and data were grouped into six primary categories based on sex (F, M) and age (18-24, 35-44, 62-74). The data include: measures of head, neck and body anthropometry in standing and simulated automotive seating positions, three-dimensional range of motion of the head and neck, head/neck response to low-level acceleration, and both stretch reflex time and voluntary isometric muscle force in the lateral direction. Reflex times are found to vary from about 30 to 70 ms with young and middle aged persons having faster times than older persons, and females having faster times than males. Muscle strength decreases with age and males are, on the average, stronger than females.