Comparison of four methods for carrying a fiberglass extension ladder

Abstract This paper describes the results of two studies aimed at comparing four methods of carrying a fiberglass extension ladder. The first study was conducted in the actual work conditions while the other took place in ideal laboratory conditions. Twenty-one telephone technicians participated in the field study while seven participated in the laboratory study together with three subjects having no prior experience with heavy ladder handling. In the field study, the technicians were asked to carry their ladder with each of the four carrying methods. After the completion of each carrying task, the technician rated the method he had just tried on seven subjective measures. Technicians' heart rate was monitored during the complete experiment. In the laboratory study, a similar protocol was used with the difference that the carrying tasks were longer since oxygen uptake was also measured. All telephone technicians had no prior knowledge or practice with three of the carrying methods tested: they had experience only with the carrying method they use in their daily work. Results of the field study show that carrying a fiberglass extension ladder on the shoulder with the arm `Through-the-rungs' imposed the least strain on the cardiovascular system and this method was judged better than or at least equivalent to the carrying method in current use. The results of the laboratory experiment were consistent with those of the field study. The other two methods tested yielded a performance that was inferior to that of the method currently used by telephone technicians in both the field and laboratory studies. The results further show that the study performed in actual work conditions had better validity than the study performed in the laboratory. Relevance to industry Handling of a ladder in varied and adverse environmental conditions is typical in the work of telephone technicians. A better knowledge of safe ladder carrying methods is an important step towards reducing the ladder-handling-related injuries. The results of this study apply to construction workers, electricians, various power utility workers and cable television installers as well.