Factors Affecting Material-Cart Handling in the Roofing Industry: Evidence for Administrative Controls

Area of Science:

• Occupational Ergonomics
• Construction Safety Engineering
• Biomechanics

Background:

• Material-cart handling is a common task in construction, often leading to strenuous exertion and overexertion injuries.
• Factors such as cart condition, tire type, environmental constraints, and load significantly impact the ergonomics and productivity of cart operations.

Purpose of the Study:

• To comprehensively analyze the interplay between cart condition, tire type, environmental factors, and load on cart handling ergonomics and productivity.
• To identify specific risk thresholds and safe operating parameters for material-cart handling in construction settings.

Main Methods:

• Eighteen roofing carts with varying conditions and tires were tested by a single subject on three distinct laboratory tracks simulating construction environments (L-shaped, ramps, obstacles).
• Multiple linear regression analysis was employed to quantify the main and interaction effects of tested factors on cart operations.

Main Results:

• Aged carts were found to increase injury risk by up to 30.5% and decrease productivity by 35.4%.
• An open space of over 61 cm is recommended between a cart and ramps/obstacles for safe operation.
• At-risk thresholds for ramp slopes and obstacle heights, along with safe load capacities, were identified for various construction site conditions.

Conclusions:

• The study provides evidence-based recommendations for administrative controls to mitigate overexertion injuries and enhance performance in material-cart handling.
• Optimizing cart condition, ensuring adequate clearance, and adhering to safe load limits are critical for improving safety and productivity in construction.