Estimation of the kinetic energy dissipation in fall-arrest system and manikin during fall impact.
Wu-JZ; Powers-JR; Harris-JR; Pan-CS
Ergonomics 2011 Apr; 54(4):367-379
Fall-arrest systems (FASs) have been widely applied to provide a safe stop during fall incidents for occupational activities. The mechanical interaction and kinetic energy exchange between the human body and the fall-arrest system during fall impact is one of the most important factors in FAS ergonomic design. In the current study, we developed a systematic approach to evaluate the energy dissipated in the energy absorbing lanyard (EAL) and in the harness/manikin during fall impact. The kinematics of the manikin and EAL during the impact were derived using the arrest-force time histories that were measured experimentally. We applied the proposed method to analyse the experimental data of drop tests at heights of 1.83 and 3.35 m. Our preliminary results indicate that approximately 84-92% of the kinetic energy is dissipated in the EAL system and the remainder is dissipated in the harness/manikin during fall impact. The proposed approach would be useful for the ergonomic design and performance evaluation of an FAS.
Ergonomics; Fall-protection; Kinetic-energy; Posture; Safety-measures; Safety-practices; Safety-research;
Author Keywords: fall-arrest equipment; energy; impact; drop test; lanyard
John Z. Wu, National Institute for Occupational Safety and Health, Morgantown, WV 26505