The development of technology for arresting falls using textiles
This cooperative research work is concerned with the development of fall arrest equipment constructed from textile materials for use in mountaineering, caving and industrial safety applications. The range of webbings available for use in fall arrest equipment is examined, and some basic experiments to determine the effect of severe abrasion are described. The methods of stitching slings (loops of webbing) are examined, and the effects of external abrasion on conventional lap joints and bartacked joints are compared. The development of harnesses is examined and the factors affecting their future design are considered. The major part of the work is concerned with the way in which the energy of a falling body is absorbed in a fall arrest system and with the peak impact loads imposed on the system's components. To measure these loads, apparatus was developed at the cooperating company's premises, together with appropriate instrumentation. A series of tests were carried out to determine loads in falls of increasing severity. The ensuing development work concerned textile shock absorbers, which are designed to limit the impact force in a fall to a predetermined maximum. Using the drop test apparatus, it was shown that such shock absorbers have very little practical effect in a climbing situation. However, the principles embodied in these devices were used to develop an industrial safety lanyard with an integral shock absorber which conforms to British Standard 1397. This device is lighter and more compact than others currently on the market and represents a step forward in the field.