The aim of this study was to assess postures andmovements of the trunk and upper arm during paper mill work, and to determinethe extent to which they differ depending on method of assessment. For each oftwenty-eight paper mill workers, postures and movements were assessed duringthree full shifts using inclinometer registration and observation from video. Summary metrics for each shift, e.g.,10^th, 50^th, and 90^th posture percentile, were averagedacross shifts and across workers. In addition, the standard deviation between workers,and the standard deviation between shifts within worker were computed. The resultsshowed that trunk and arm postures during paper mill work were similar to otheroccupations involving manual materials handling, but the velocity of armmovements were lower. While postures determined by inclinometry and observationwere similar on a group level, substantial differences were found betweenresults obtained by the two methods for individual workers, particularly for extremepostures. Thus, measurements by either method on individuals or small groupsshould be interpreted with caution.