This short presentation describes a preventable workplace incident where a worker in Washington state was killed on the job, and is narrated by the L & I safety inspector who conducted the investigation. To view the narration script, click on the button on the lower right hand corner of the screen. To move between slides or look at a particular slide again, click on the same lower right hand corner button and then click on the back and forward buttons at the bottom of the screen.
Hello, my name is Gary Sadowski and I am a safety and health specialist with the Department of Labor & Industries, Division of Occupational Safety and Health. In 2009, I was assigned to investigate the death of a young iron worker at a large construction site.
Vertical rebar cages were being built at this construction site. Rebar cages are embedded inside concrete pillars or columns to provide greater tensile strength. These large structures are built horizontally and then lifted into a vertical position with a crane. They must be temporarily held in place with braces until they can be permanently secured. After they are secured, concrete is poured around them to form the finish pillars.
On this job a crane had hoisted the 30 foot cage into position, similar to the photo on the left. Two workers were working on the cage making adjustments to the rebar which was held temporarily in place with 2 X 4 wooden braces shown in the photo on the right. At this construction site, these cages were two-tiered, meaning they were twice the height and weight of a normal 15 foot single-tiered cage. One worker was near the top of the cage and the other worker was on the lower portion of the tower. During this process the ironworkers are required to attach their fall protection to the cage.
The rebar cage had been unhooked from the crane but it quickly developed a noticeable lean. So one of the ironworkers began climbing up the cage to re-hook it to the crane. Unfortunately one of the wooden braces had a large knot in it which greatly weakened it's strength. This wooden brace snapped at the knot and the cage toppled over before it could be hooked to the crane. The lower ironworker was able to scramble free from collapsing tower but the ironworker near the top was not able to escape and was fatally crushed by the nearly three-ton tower when it toppled over. He had managed to undo his fall protection, but could not jump away from the falling tower soon enough. The following slide shows an animation of this incident.
This photo shows the two by four brace that was being used with the break at the knot.
The company was cited for not providing adequate guys or braces for this type of rebar construction work. The solution was to use steel tilt-up braces similar to those used in tilt-up concrete work. Let's keep Washington Safe and Working by always using steel braces to hold up rebar cages in construction projects.