A system, comprising: a computing device configured to obtain video signals of a worker performing a hand-related job at a workplace; and a computing server system configured to receive and process the video signals to identify hand grips and wrist bending involved in the job, determine a hand grip type for each identified hand grip, obtain force information relating to each identified hand grip, determine neutral or hazardous wrist bending based at least upon the wrist bending and the hand grip force information, calculate a percent maximum strength for each identified hand grip, calculate frequencies and durations of each identified hand grip and wrist bending, and determine ergonomic risks of the hand-related job accordingly.