Inter-rater reliability of video-based ergonomic job analysis for maintenance work in mineral processing and coal preparation plants

A large proportion of fatal and non-fatal injuries in mineral processing and coal preparation plants can be attributed to maintenance and repair work. Maintenance work in the mining industry has received little attention due to the challenges associated with collecting and evaluating information on exposures to risk factors and possibly due to the adverse working conditions. The goal of this study was to develop a reliable method to systematically quantify exposures to environmental attributes and physical task demands for maintenance work in mineral processing and coal preparation plants. Hierarchical task analysis was carried out for commonly observed and reported maintenance tasks. A detailed taxonomy of environmental features and physical task demands thought to contribute to injury was created. Two raters independently coded 41 videos using the Multimedia Video Task Analysis™ software to measure the percentage of task time that workers were exposed to each of the variables defined in the taxonomy. For most exposure variables, the mean differences in exposures coded between raters were low and the correlations of exposure durations were high. For variables in which the mean differences in exposure were considered to be too high, modifications to the approach were made to improve measurement reliability. This study provides some evidence to suggest that video based ergonomic job analysis is a viable tool for characterizing the environmental and physical demands of maintenance work in mineral processing and coal preparation plants.