Accession Number : ADA309219

Title :   The Effects of Seat Cushions on Human Vibration Response: Comparison of the Effects of Whole-Body Vibration Exposure Between Females and Males.

Descriptive Note : Final rept. 1 Dec 94-30 Sep 95,

Corporate Author : ARMSTRONG LAB WRIGHT-PATTERSON AFB OH

Personal Author(s) : Smith, Suzanne D.

PDF Url : ADA309219

Report Date : MAY 1996

Pagination or Media Count : 57

Abstract : Discomfort, performance degradation, and increased health risk have been associated with prolonged exposures to vibration occurring in the operation of civilian and military vehicles. while an increasing number of females are selecting these occupations, the existing vibration standards and exposure limits are based on the male population. The objective of this study was to compare the biodynamic responses of females and males exposed to whole-body vibration. This final report includes the evaluation of resonance behaviors observed in the driving-point impedance, and in the chest, head, and spine transmissibilities at two acceleration levels for the rigid seat and with the use of seat cushions. While the primary resonance frequency (4-8 Hz) was not significantly affected, the peak impedance magnitudes, normalized for body weight, were significantly less for the females as compared to the males. The chest transmissibility results were more variable. There was a tendency for the horizontal chest motion to be lower and the vertical chest motion to be higher in the females as compared to the males. No clear trends were observed in the vertical head and spine transmissibility peaks. The results indicated that differences exist between females and males in the distribution of mass, stiffness and damping properties of specific anatomical structures contributing to the observed biodynamic responses.

Descriptors :   *VIBRATION, *MILITARY VEHICLES, *EXPOSURE(PHYSIOLOGY), *SEATS, *POSTURE(PHYSIOLOGY), RISK, DEGRADATION, DISTRIBUTION, HUMANS, HEALTH, ACCELERATION, MASS, DAMPING, MOTION, POPULATION, RESONANT FREQUENCY, VERTICAL ORIENTATION, LIMITATIONS, RESONANCE, STANDARDS, PATTERNS, MALES, BEHAVIOR, HORIZONTAL ORIENTATION, PAIN, THORAX, RESPONSE(BIOLOGY), RIGIDITY, BODY WEIGHT, FEMALES, SPINAL COLUMN, BIODYNAMICS, PADS(CUSHIONS).

Subject Categories : Stress Physiology
      Logistics, Military Facilities and Supplies

Distribution Statement : APPROVED FOR PUBLIC RELEASE