An Evaluation of Adult Clasping Strength for Restraining Lap-Held Infants

Abstract

Quasi-static and dynamic pull tests were conducted to measure the maximum forces that adults can voluntarily exert in holding a 7.9 kg infant dummy (age 6 months) in their laps. The results indicate that the forces that lap and shoulder belted adults can exert in holding an infant dummy in their laps are far less than the inertial force that would be exerted by a 7.9 kg infant decelerated at more than 30 Gs. Thus in a motor vehicle frontal barrier crash at 50 km/hr, an infant even when held tightly by a restrained adult would almost certainly strike the dash or windshield. Similarly in airplanes, in crash or turbulence situations, the lap-held infant is likely to hit nearby hard structures. The results clearly demonstrate that it is not safe for infants to be transported in adults’ laps in automobiles or airplanes even in the relatively rare instances when they are held tightly and the adults are restrained. © 1979, Human Factors and Ergonomics Society. All rights reserved.