Are posture data from simulated tasks representative of field conditions? Case study for overhead electric utility workers.

Many ergonomics studies are conducted in laboratory-simulated work environments to assess risks for the development of musculoskeletal disorders under more controlled conditions. However, the simulated conditions could be of questionable validity with respect to reproduction of field conditions involving risk factors. The objective of this study was to verify whether the postures recorded for neck extension/flexion and upper arm elevation of overhead electric utility workers in a simulated environment were similar to those recorded in a field environment. Of the three frequently performed tasks analysed, two presented similar exposure in both conditions. However, differences were identified for a more complex task (relay replacement). These results suggest that simulated tasks may be more representative for more standardised tasks. This may indicate that researchers investigating risks should avoid simplifying complex tasks when reproducing field posture exposure in laboratories, since omitting extra subtasks may lead to an inaccurate reproduction of field exposure. Practitioner Summary: Studies comparing results from field and simulated environments are necessary to evaluate to what degree postural exposure reproduced in laboratory is representative of the exposure occurring in real work situations. This is particularly relevant for tasks involving training in simulated environment due to safety constraints.

Postures and movements in the most common tasks of power line workers.

The repair and maintenance of electrical power lines involves awkward postures, which are known risk factors for developing musculoskeletal disorders. The aim of the present study was to quantify postures and movements of upper arm, head, upper back and neck in the main tasks performed by line workers. Posture of twelve right-handed line workers was recorded by inclinometry and presented as percentiles of angular and angular velocity distributions. All tasks involved considerable upper-arm elevation, ranging from 73° to 115° for the 90th percentile. Upper-arm elevation showed significant differences between tasks, but no consistent differences between right and left sides. Regarding velocity, the right arm presented higher levels than the left arm. All tasks required significant extension of head, upper back and neck, ranging from 7° to 67° for head (10th percentile). All tasks, except the one performed with a continuous extension, also involved pronounced flexion, ranging from 33° to 60° for the head (90th percentile). Work which required highly elevated arms also required significant head extension (r(2)=0.56). Awkward postures of upper arms, head, upper back and neck were identified by inclinometry, demonstrating the need for preventative interventions to reduce musculoskeletal disorders among line workers.

Técnicas seguras e ergonomicamente adequadas aos trabalhos de desgalhamento de árvores e enleiramento de toras / Safes and ergonomics technics for works of unbranchment of trees and alignment of logs

Trabalho vencedor do VI Prêmio SEPACO visa demonstrar a eficácia alcançada nas técnicas de desgalhamento de árvores e enleiramento de toras a partir da alteraçäo da postura dos funcionários e da adequaçäo da ferramenta utilizada