At this high-rise construction site, cleaning an air vent shaft would become deadly.
This is what happened.
Firm A was the prime contractor of the job site.
Personnel working for Firm A included a superintendent,
a construction safety officer or CSO, and a foreman.
Firms B and C were construction labour supply firms.
The workers performing the cleaning were employed by these firms and took their direction from
Firm A's personnel.
About two weeks before the incident the superintendent told the foreman that debris needed to be
cleaned out of the shaft.
The shaft was about 168 feet long, 10 feet deep, and only about 2 feet wide.
At the west end was a serious fall hazard: a vertical shaft for the parkade air intake.
Metal grates covered part of the horizontal shaft.
Daylight through them provided the only illumination inside the shaft.
At the east and west ends of the shaft the grates were temporarily removed to enable
access using ladders.
On the day of the incident, the CSO developed a safe work procedure or
SWP with workers 1 and 2.
The foreman reviewed the SWP with the two workers and signed it off.
The three of them, along with the CSO, went to the work area and conducted the field-level
hazard assessment.
Later Worker 1 descended into the shaft to clean it out.
He used shovels and brooms to gather debris, which he put into a bucket.
Worker 2, at ground level, retrieved the bucket when it was full.
He was also to keep in constant voice communication with Worker 1,
as per the SWP.
After about two-and-a-half hours, Worker 1 said he was finished cleaning.
The foreman told Worker 3 to help workers 1 and 2.
Worker 2 asked Worker 3 to stay in the area while he went to get a skid steer loader for
loading the debris.
By this time the foreman and supervisor had left the job site.
Worker 1 told Worker 3 that he had to go to check the west end of the shaft to see if
there was anything else to clean up.
Minutes later Worker 3 heard a thud.
He called out for Worker 1 but got no response, so he went into the shaft and ran towards
the west end to look for him.
When it became too dark to see, he stopped and used his cell phone light.
He found himself standing about 2 feet from the vertical shaft opening.
He ran back out and told Worker 2 that he believed Worker 1 had fallen down the shaft.
Worker 2 contacted the CSO and first aid attendant.
Meanwhile, Worker 3 went to the parkade level.
He opened the access shaft and found Worker 1.
Efforts to revive Worker 1 failed.
How can we prevent similar incidents?
Have a fall protection system in place.
The direct cause of this incident was the lack of a fall protection system.
Removing the grates, that had been acting as guards, opened up access to the vertical
shaft.
What were the underlying factors?
One.
Inadequate risk assessment.
The work area was visually inspected only from the ground level and didn't take into
account the danger of the vertical shaft.
Site drawings weren't reviewed to identify the location of potential hazards.
Two.
Ineffective safe work procedure.
The SWP acknowledged fall hazards but didn't describe what those hazards were or how to
prevent them.
The vertical shaft wasn't restricted from entry.
There were no warning signs, no protective safeguards,
and not even lighting to see the danger.
Three.
Lack of communication.
Many people on the jobsite were aware that a vertical shaft was connected to the horizontal
shaft, but no one told Worker 1.
The foreman said he knew of the shaft, but didn't know exactly where.
He and the CSO stated that the work was to take place only between the two ladders and
not further into the horizontal shaft.
This was not in the SWP nor discussed with the workers.
Four.
Inadequate supervision.
The workers were unsupervised when the superintendent and foreman left the jobsite for the day.
Five.
Inadequate planning.
The development of the SWP and the set-up of the cleaning task only occurred on the
morning of the incident.
Because this was after that morning's site safety meeting,
the cleaning of the shaft wasn't discussed at that meeting.
Had the task been discussed, the superintendent might have reminded the
foreman about the open vertical shaft.
In the year of this incident, eight other B.C. construction workers died from falls.
Help save lives: learn from what happened here.