Physical Ergonomic Assessment in Cleaning Hospital Operating Rooms Based on Inertial Measurement Units

Workers involved in hospital operating room cleaning face numerous constraints that may lead to musculoskeletal disorders. This study aimed to perform physical ergonomic assessments on hospital staff by combining a continuous assessment (RULA) based on inertial measurement units with video coding. Eight participants performed cleaning tasks while wearing IMUs and being video recorded. A subjective evaluation was performed through the Nordic questionnaire. Global RULA scores equaled 4.21 +/- 1.15 and 4.19 +/- 1.20 for the right and left sides, respectively, spending most of the time in the RULA range of 3-4 (right: 63.54 +/- 31.59%; left: 64.33 +/- 32.33%). Elbows and lower arms were the most exposed upper body areas with the highest percentages of time spent over a risky threshold (right: 86.69 +/- 27.27%; left: 91.70 +/- 29.07%). The subtask analysis identified 'operating table moving', 'stretcher moving', and 'trolley moving' as the riskiest subtasks. Thus, this method allowed an extensive ergonomic analysis, highlighting both risky anatomical areas and subtasks that need to be reconsidered.