Wood chippers are often used this time of year to chop up fallen branches—and to turn Christmas trees into mulch after the holidays. Tree branches and trunk sections fed manually into the machine’s infeed hopper are grabbed by the feed mechanism or chipper knives, which cut and propel wood chips through the discharge spout. So clearly this equipment can be very dangerous if not used properly.
On Dec. 9, 2015, a 19-year-old worker from North Carolina was killed on his first day on the job after being pulled feet first into a wood chipper. He was trying to kick a tree branch that got jammed in the machine when he was pulled into it. His employer hit the kill switch and put the machine in reverse, but it was already too late.
A similar incident happened to a young worker in BC. Two workers were chipping blackberry bushes that had been gathered into a pile. The young worker raked up the remaining debris, put it into the hopper of the mobile wood chipper and then used his foot to kick the rakings farther in towards the chipper’s infeed rollers.
He slipped on the snow-covered ground and inadvertently grabbed the spring-loaded feed control bar, activating the infeed rollers. His foot got pulled towards the chipping blades. Fortunately, his co-worker quickly shifted the control bar into reverse to free the young worker’s foot, which was only fractured.
The NIOSH Science Blog says that, to protect workers from being caught by the chipper feed mechanism, employers should ensure the following:
- All safety devices and controls, such as emergency shut-off devices, are tested and verified to be functioning properly before the chipper is used.
- Workers are trained in safe work procedures, including operating wood chipper safety devices and safety controls. These procedures should be based on the manufacturer’s recommendations for each machine.
- At least two workers are in close contact with each other when operating the chipper.
- Workers wear close-fitting clothing, gloves without cuffs, trousers without cuffs, and skid-resistant foot wear. Clothing should be kept tucked in.
- Workers’ hands and feet remain outside the infeed hopper.
- Workers feed brush and limbs into the infeed hopper butt end first.
- Workers feeding material are positioned at the side of the machine to allow quick operation of the emergency shut-off device and minimize risk of entanglement in branches. Because of differences among machines, the manufacturer’s operating manual should be consulted for guidance. Safe feeding of some disc-type chippers requires the worker to be on the right side.
- Workers walk away once the feed mechanism has grabbed the material.
- Workers lay short material on top of longer material that’s feeding or use a longer branch to push it through the infeed hopper.
- Workers load small raked-up material such as twigs and leaves directly into the chip truck or in trash cans or bags instead of feeding it into the chipper.
- Workers keep the area around the wood chipper free of slipping and tripping hazards.
- Workers wear hard hats, eye protection and hearing protection.