Industrial Ergonomics, Manual Material Handling – ACGIH TLV for Lifting
A worker manually lifts trays of clean dishes from a conveyor at the end of a dishwashing machine and loads them on a cart as shown in Figure 1. The trays are filled with assorted dishes (e.g., glasses, bowls, plates, etc.) and silverware. The job takes between 45 minutes and one hour to complete, and the lifting frequency rate averages 5/minute.Workers usually twist to the left side of their body to retrieve the trays and then twists to the right side of their body to lower the trays to the cart. The trays have well-designed handhold cutouts and are made of lightweight materials.