While replacing a belt on a quarry conveyor system, an employee was struck by a belt tensioner at around 11:00 a.m. Suffering from multiple muscle and bone injuries, the employee was taken to hospital and operated on.

The belt needed to be replaced after the supervision system had detected a rotation fault on the conveyor. Upon opening the inspection hatch at the front of the conveyor belt, the technician saw that the belt was torn across its width. The entire conveyor system was shut down.

The site’s work correspondent and the maintenance contractor jointly decided to use a forklift truck to pull off the old belt and install the new one. The new belt was spliced to the old one at the tail drum and a bolted tensioner was fitted on the belt at the head drum. The assembly was then tied to the forklift by a rope.

As the forklift driver’s view was hampered, especially due to glare from the sun, the site’s work correspondent asked the soon-to-be-injured employee to move to a spot where he could send hand signals to the driver.

After getting stuck as it passed through the guide rollers, the tensioner made a roller fall. The pulling force caused the tensioner to strike and ricochet off the frame of the perpendicular conveyor belt, hitting the employee, who was standing at a 30° angle from the axis of the line of fire, and making a 10 cm gash in his left calf. The injured employee was placed on sick leave until 7 March.

It was later found that one of the tensioner’s clamping bolts was broken.