A Brink Forest Products Ltd. employee who was seriously injured while preparing to change the knife assemblies on a wood waste chipper was carrying out the work while the machine was still moving, according to a WorkSafeBC incident investigation report.
The report, which stems from a November 2014 incident, said the worker was on the day shift but was part of the crew that reported to work earlier in order to change the blades, which is done prior to every shift.
According to evidence deduced by the WorkSafeBC investigator, he turned off the chipper disconnect and entered the chipper room while the machine’s disc was still rotating.
To reach the knife assemblies, secured on a 48-inch disc that turn on a shaft supported by external bearings located on both sides of the chipper frame, he removed the two bolts fastening the protective shroud to the machine frame.
“The metal hinge securing the bottom of the shroud to the chipper frame was able to
move from side to side about 1.27 centimetres,” the report said. “Once the two bolts were removed, the vibration of the chipper caused the shroud to move sideways, enough for the knife assemblies and then the fins to contact the rotating disc. The transfer of energy from the rotating disc to the shroud caused the shroud to open with considerable force and a loud bang [striking and seriously injuring the worker.]”
Other workers who were interviewed by the inspector said it takes up to 15 minutes for the chipper to come to a complete stop. An 18-step “safe work procedure” was posted in the chipper room for changing the knives, but “wait for equipment to come to a complete stop” was missing, the report noted.
The investigator also found that while the worker had carried out the task previously, he was authorized to do so only with oversight, typically by the lead hand. On the day in question, “he was not signed off and authorized to do the work without oversight.”
The employee’s name and details about the injury were redacted from the report, completed about a year after the November 2014 incident and provided to The Citizen this month following a request to the agency for the document.
The investigator concluded there was inadequate information about the hazards associated with kinetic energy and “specific instructions for shutting down and locking out the chipper” were lacking. And he found the worker should have been supervised as he was carrying out the task.
In June, Brink Forest Products was fined $68,773.47 for the incident. And since the incident, WorkSafeBC has conducted 14 site visit inspections at the site, said agency spokeswoman Trish Chernecki.
“All orders issued by WorkSafeBC have been complied with at this time,” Chernecki said.