Assessing Lower Extremity Kinematics of Roofing Tasks: Fid-Bau Portal

Assessing Lower Extremity Kinematics of Roofing Tasks

Jahani Jirsaraei, Matin / Esmaeili, Behzad / Pathak, Parth

Roofers spend considerable time in awkward postures due to steep-slope rooftops. The combination of these postures, the forces acting on them, and the time spent in such postures increases the chance of roofers developing musculoskeletal disorders (MSDs). Several studies have connected these awkward postures to potential risk factors for injuries and disorders; however, existing models are not appropriate in roof workplaces because they are designed to assess work-related risk factors for general tasks. This study examines the impacts of work-related factors, namely working posture and roof slope, on kinematics measurements of body segments in a laboratory setting. To achieve this objective, time-stamped motion data from inertial measurement unit (IMU) devices (i.e., accelerometer, gyroscope, and quaternion signals) were collected from a sample of six undergraduate students at George Mason University. Participants performed two common roofing activities, namely walking along the roof and squatting in different roof slopes (0°, 30°). Comparing IMU signals using statistical analysis demonstrated significant differences in body kinematics between roofing activities on the slope and level ground. Overall, sloped-surface activities on a 30° roof resulted in changes in about 26% of walking and 12% of squatting variables. Such information is useful for a logical understanding of roofing MSD development and may lead to better interventions and guidelines for reducing roofing injuries.