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Wood products manufacturer fined $65K after worker injured in machine


A wood products manufacturer has been fined $65,000 in Ontario court after a worker was injured by a strapping machine.

Following a guilty plea, Norbord Inc., headquartered in Toronto, was fined for an incident at its mill Berwick, Ont. The court also imposed a 25-per-cent victim fine surcharge, credited to a special provincial government fund to assist victims of crime.

The strapping machine is among one of the machines involved in the production of oriented strand board (OSB) at the mill. The strapping machine is designed to automatically apply strapping to bundles of newly produced OSB prior to their shipment.

Wood packing material known as dunnage as well as edge protectors are also automatically put in place to protect against damage.

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In this case, the programmable logic controller (PLC) controls the automatic function of the strapping machine and its various conveyors. Several sensors ensure that each bundle of OSB, dunnage and edge protectors are in place before the strapping operation occurs.

In automatic mode, the PLC starts the conveyor to move the bundle into the strapping machine. When the sensors signal to the PLC that the bundle is in the correct position, the PLC stops the conveyor. The PLC then energizes a ram to push the dunnage into position under the bundle.

When the dunnage is in the correct position, it contacts something known as the “flop gate” or actuator, which has a sensor connected to the PLC. The top portion of the strapping machine (the platen) then hydraulically lowers to compress the bundle; strapping is applied around the bundle, dunnage and edge protectors. The conveyor then moves the bundle forward and the process is repeated for a second strap on the bundle.

An investigation by the Ministry of Labour, Training and Skills Development showed that on Oct. 23, 2018, the strapping machine was running in automatic mode when it suddenly stopped after moving an OSB bundle into position.

A worker approached the front of the machine to investigate and troubleshoot the problem. The worker discovered that an edge protector had fallen and was preventing the movement of the flop gate/actuator. Since the flop gate/actuator wasn’t in the expected position, the PLC didn’t receive the signal required to proceed further.

The worker bent over to pick up the edge protector from where it had fallen. As soon as the edge protector was removed, the flop gate/actuator moved, which caused the PLC to receive the signal to proceed with the strapping operation. The platen lowered and the worker was caught between the bundle and the platen, suffering an injury.

The ministry found that there were no guards or other devices in place to prevent access by a worker to the hazardous moving parts of the strapping machine, contrary to the safety measures in the Occupational Health and Safety Act.