Obese Forklift Operator Neck Loads and Back Loads on a Sit Down Lift Truck During a Sudden Drop

Neck and back loads of sit down forklift operators have not been fully evaluated in the scientific literature. In this study, we evaluate the neck and back loads of an obese forklift operator who experiences a sudden vertical drop while operating a sit down lift truck. A ballasted 50th percentile male anthropomorphic test device (ATD) was used to measure loads available to a sit down forklift operator. Telemetry was used to remotely operate the sit down lift truck with the ATD properly belted. The belted ATD and lift truck were traveling, forks-leading along a stationary flatbed trailer when the right front forklift tire dropped into a defect in the floor. Several runs were performed at forklift travel speeds less than 5 miles per hour (2.2 meters per second). Back loads of the ATD were compared to activities of daily living (ADLs); and neck and back loads of the ATD were compared to published human tolerance levels and Injury Assessment Reference Values (IARVs) used in compliance testing. Review of ADLs, IARVs, and tolerance data show little correlation between the potential for spinal injury and experiencing a sudden drop while operating a sit down lift truck.