Safely operating a wood chipper

Self-feeding wood chippers commonly are used in tree trimming operations. With chipper discs or drums spinning at anywhere from 1,000 to 2,000 rotations per minute, the equipment can be very dangerous if not handled properly.

If workers who are feeding material into the hopper trip or lean too far, they risk becoming entangled in branches and being fed into the chipper themselves. Workers also are at risk of being struck by debris being thrown by the wood chipper if hoods are unlatched, damaged or improperly secured.

To prevent these types of injuries, NIOSH recommends:

• Train all workers in proper work procedures in accordance with the manufacturer’s specific recommendations for each machine.
• Test to verify all safety guards and controls – including emergency shut-off devices – are working properly before using the chipper.
• Be sure the hood covering the chipper’s knives is completely closed and latched before starting the machine.
• Assign at least two workers to remain in close contact when operating the chipper.
• Wear close-fitting clothing, gloves without cuffs and skid-resistant footwear. Keep clothing tucked in.
• Feed limbs and brush into the hopper butt-end first, and be sure to keep hands and feet outside of the hopper.
• Stand at the sides of the machine when feeding materials to minimize the risk of entanglement and ensure access to the emergency shut-off device. Once the feed mechanism has grabbed the material, walk away from the machine.
• Lay short material on top of longer material that is feeding, or use a long branch to push short materials through the hopper.
• Load small material such as twigs and leaves directly into the chip truck or trash cans rather than feeding it into the chipper.