Falls into via ferrata climbing sets carry a higher injury risk for lightweight climbers

Abstract

A via ferrata (Italian for ‘iron road’) is a climbing route with fixed iron climbing aids in steep, rocky mountain terrain. Climbers attach themselves to the climbing aids with a via ferrata set (a certain safety equipment designed for vie ferrate) and a harness. In case of a fall the via ferrata set should prevent injuries by reducing the deceleration of the falling body. Different standards exist worldwide for the deceleration and forces acting in the case of a fall; the European standard is evaluated for 80 kg heavy individuals. In this paper the acceleration and force differences for different climber weights – especially lightweight climbers – are evaluated. For this purpose four different NCAP frontal crash dummies representing humans of different weights and ages (3 y, 15 kg; 10 y, 34 kg; female adult, 48 kg; male adult, 77 kg) were dropped from a height of 5 m into different via ferrata sets. During a fall accelerations and braking forces were measured, A/D converted with a frequency of 1024 Hz and 1000 Hz, respectively and recorded on a PC. Additionally synchronous video data were recorded with two cameras (240 fps, 448 $\times$ 336 px). A total of eight via ferrata sets of two different types were evaluated: (1) modern web-based sets where a webbing is ripped apart and absorbs energy (tearing energy absorbers), and (2) cheaper rope-braking systems which absorb energy by friction (friction energy absorbers). The results show that the maximum braking forces allowed in the European standard were exceeded in several cases. Maximum braking distances were not used to full capacity in any of the trials. Thus, falls could have caused injuries especially for lightweight climbers. Hence, according to the gathered data a minimum weight limit for via ferrata sets should be established. European standards should be adopted in consideration of the presented results of this study.