Failing to use a safety harness properly, smoking cannabis on the job and a problem with a crane lift are facts in the death of a worker on BC Hydro’s Northwest Transmission Line last year, according to a BC coroner’s report.
Michael Todd Thornewell, 45, died of massive head trauma after falling 22m from a work platform suspended by a crane while working at a tower on the power line, about 50 km north of Terrace on March 15, 2014.
“It was determined that Mr. Thornewell had not followed appropriate safety procedures as his fall protection harness was not fastened to one of the six tie-off points that were welded to the guardrail corners,” said the report written by coroner Wendy Flanagan.
“I find that Michael Todd Thornewell died near Terrace on March 15, 2014 of massive head trauma due to a fall from a crane. Recent use of cannabis may have been a contributory factor. I classify this death as accidental and make no recommendations,” wrote Flanagan.
Thornewell, who had been working for McGregor Construction of Edmonton under contract to main transmission line builder Valard, was a power line technician working on a new transmission tower March 15, said the report.
During construction, new transmission lines, or conductors, are strung between transmission towers with the lines temporarily held in place with chain jacks between the insulator glass at the towers and implosion sleeves, said the report.
Newly strung conductors are secured permanently to the insulation hardware and the tower by “pinning in,” continued the report.
Conductors, with their implosion sleeve and attachments eyes, are then ready to be connected to the turnbuckle at the insulator glass, said the report.
“In order to perform this work, two workers are elevated in a crane-supported work platform that is pinned to an attachment mounted to the tip of a truck-mounted crane’s telescoping boom.
“The workers instruct the crane operator to position them under the chain jacks to prepare for pinning in the conductor,” said the report.
Twelve workers on three crews took a break at 5:30 p.m. and afterward, Thornewell and a co-worker were elevated 22 m to their work position, continued the report.
The crane operator, who controls the engine with a foot pedal that controls the boom’s hydraulic system, was standing next to the base of the boom just behind the cab of the truck, continued the report.
He “could not directly see Thornewell or the right side and bottom of the work platform and was following the co-worker’s hand signal to lower the boom.
“The operator tried to boom down but the platform did not move.
“He was again signalled to boom down but still nothing moved as the work platform was hung up on components of the conductor.
“When the tension created by the hang-up released, the work platform was freed, causing the crane boom and work platform to suddenly drop several metres.
“The platform then swung violently at the pinned connection point between the work platform and the attachment to the crane.”
Thornewell was thrown from the platform and fell on his back where he was found with no vital signs, continued the report.
The company’s first aid personnel started CPR and he was transported with a workplace emergency vehicle, said the repot.
“BC Ambulance Services personnel met the emergency vehicle at the Cedar River Bridge at approximately [6:28 p.m.] and continued with resuscitation efforts without success,” continued the report.
Thornewell had extensive training in fall protection and his lineman certification, which he had received in Alberta in 2010, said the report.
The work platform had a hand friction brake that would reduce the swinging of the platform, continued the report.
“An inspection of the unit determined that there were no defects that would have caused the incident and that the hand brake had not been applied at the time of the incident,” read the coroner’s report.
Additionally, the report said “Thornewell was witnessed to have smoked cannabis during the break at [5:30 p.m.], just prior to returning to work.”
Cannabis was found in his system “which indicated recent use,” according to a toxicology report which also said the results “indicated use of cocaine.”
Coroners are charged with finding facts and not fault involved in a death.