Assessment of Ergonomic Exposures among Operators of Construction Equipment

Abstract

Although numerous studies have shown an association between operation of heavy construction equipment and symptoms of musculoskeletal disorders, very little research has been performed that objectively characterizes the exposure of operating engineers to ergonomic hazards. The objectives of this study were to evaluate: 1) the vibration at the seat/operator interface (X, Y, and Z axes); 2) the transmissibility of vibration in the Z-axis; 3) the psychophysical ratings of vibration level and vibration discomfort; and 4) the postural requirements of the job. The results of this study indicate that the digging operation had higher levels of total weighted acceleration than high or low idling. The transmissibility data showed that the seat was amplifying vibration particularly in the lower frequencies. The seats in the equipment demonstrated that they may not be sufficient in protecting operators from long-term effects of vibration exposure. There was high positive correlation among the subjective ratings (vibration discomfort and vibration level), but moderate positive correlation between subjective ratings and quantitative vibration levels. The postural evaluations revealed that the operators were required to assume awkward postures of the neck, shoulder, and trunk while performing their jobs.