Fall risk analysis of construction workers using inertial measurement units: Validating the usefulness of the postural stability metrics in construction

Fall accidents are a leading cause of fatalities and injuries in the construction industry, and the loss of bodily stability is one of the primary factors contributing to such falls. Body stability can be analyzed by studying dynamic and postural stability, the assessment of which can ultimately improve worker safety on the job sites. Previous studies have introduced a method for assessing construction workers' gait stability, but there remains a need for a comprehensive method that can analyze the fall-risk of construction workers' in stationary postures. This study aims to test the usefulness of two metrics-velocity of the bodily center of pressure (COPv) and the resultant accelerometer (rAcc)-as predictors with which to measure workers' fall risk in stationary postures. A laboratory experiment was designed and conducted to gather IMU data and compare the resulting stability metrics (I-COPv and rAcc) with the postural stability observed while conducting the same activities on a forceplate (F-COPv). The experiment evaluated stationary-posture tasks with various fall-risk profiles: standing and squatting in different situations (e.g. wearing a loaded harness with a symmetric and an asymmetric load, and holding a toolbox). The analysis's results demonstrated a significant difference in I-COPv and rAcc values across different postures and tasks and also showed considerable correlations between the metrics from both the force plate and the IMU sensors. The results showed the distinguishing power of I-COPv and rAcc in measuring the fall risk of different construction workers' tasks in the stationary posture.