Name three ergonomic risk factors commonly associated with manual material handling.

• A. Slippery floors, uneven ground, and poor signage.
• B. Bright lights, loud noise, and short breaks
• C. Repetitive motion, heavy or awkward lifting, and awkward postures (bending, twisting).
• D. Chemical exposure, long drives, and poor ventilation

Answer: (C)

In manual material handling, the biggest ergonomic risks come from how the body is loaded during lifting and moving tasks. The three main factors are repetitive motions, lifting that is heavy or performed in awkward ways, and postures that are bent, twisted, or otherwise out of a comfortable alignment. Repetition tires muscles and tendons, increasing the chance of overuse injuries. Lifting heavy loads or doing so with poor form or from awkward positions puts large forces on the spine and joints, especially when the load is away from the body or there’s twisting during the lift. Awkward postures keep joints out of their neutral alignment, forcing the muscles to work harder and elevating injury risk over time.

Other options describe hazards not specific to the biomechanics of handling loads: slippery or uneven surfaces relate to slips and falls; environmental factors like bright lights or loud noise, or short breaks, are not direct ergonomic load-posture risks; chemical exposure, long drives, and poor ventilation involve different kinds of safety or health concerns rather than the mechanics of manual handling.