Woodchipper Safety Guideline

May 4, 2022

Action: Where appropriate, the ORFA recommends JHSC agenda item and H&S Bulletin Board Posting

A recent sub-contractor worker death in Oshawa that involved a woodchipper is a stark reminder of the dangers associated with this type of equipment. Many grounds operations have some form of chipping equipment as part of their tool inventory or alternatively, this equipment will be used by contractors hired by a department to assist in these tasks. The increase in demand for this type of work has been prompted by the growth in recreation grounds operations and changes in weather patterns that are causing significant tree failures that need to be responded to.

A woodchipper, as its name implies, is a machine that transforms tree limbs, branches, and trunks into chips. A powerful engine turns a rotating drum set with blades or “knives” that cut the wood. The combination of speed and torque allows commercial woodchippers to pull in branches at 20 inches per second. As an operator manually pushes brush and tree limbs through the infeed chute or hopper collar into the hopper, the feed mechanism and drum blades grab anything within reach. “Anything” can include long hair, loose jewelry, rope, hand, fingers and/or an arm.

Wood chipping operations can be dangerous for those running the chipping equipment, others working nearby, and the public. When workers feed tree limbs into chippers, they are at risk of getting caught in the machine and being pulled into the chipper knives. Flying wood chips from the machine discharge chute also pose a hazard to others in the area. Regrettably, a worker being caught in the chipper and being pulled into the fast-turning chipper knives is the most common event with the remaining fatalities resulting from being “struck-by” accidents. A chipper equipped with a winch-line assembly (a “struck-by” accident) and a worker wearing gloves with cuffs being pulled into a chipper are the most common root causes.

Although the hazards associated with chipper use are generally known to operators, awareness of these hazards and the associated safeguards needs to be highlighted and reinforced. The following highlights many of the common focus points in worker and equipment use safety:

    • Review the equipment’s owner’s manual and safety precautions.
    • Familiarize yourself with all safety stickers attached to the equipment.
    • Before operating wood and brush chippers, it is important to wear proper apparel and PPE: clothing should be close fitting and tucked in. Don’t wear loose-fitting clothing like untucked or unbuttoned shirts and jackets or pants with cuffs that could get caught on loose brush and branches.
    • Hard hats and ear protection are required.
    • Eye protection is also required. It must be ANSI-approved and may consist of glasses, goggles, or a flip-down visor of plastic or mesh. ƒ Wear good work pants and leather work boots with non-slip soles.
    • Gloves are recommended, but gauntlet-style gloves should never be worn as they may snag on branches being fed into the chipper.
    • Avoid wearing any kind of jewelry such as earrings, rings, watches, or necklaces that could present a safety hazard.
    • Stack brush in a way that makes it easy for the operator to feed the chipper. Allow for a clear feed path.

After the pre-start and maintenance checks:

    • Designate one or more employees as a safety watch to be stationed near emergency shut-off devices while other employees feed material into the chipper.
    • Stand to the side of the infeed chute when feeding material into the chipper. This reduces the “caught-in” hazard and allows quick access to emergency stop devices.
    • Keep hands and feet out of the immediate infeed chute area while the chipper is running.
    • Push material into feed rollers with a wooden tool or a long branch.
    • Feed branches into the chipper butt-end first.
    • Place shorter branches on top of longer branches being fed into the chipper.
    • Place small debris into trash cans instead of feeding it into the chipper.
    • Never stand, sit, or climb onto any part of the chipper while it is running.
    • Shut down the chipper and remove the ignition key when it is unattended.
    • Before starting a chipper, ensure that the chipper’s disc hood is completely closed and latched, and that there are no foreign objects in the infeed area.
    • Ensure that the discharge chute is positioned to prevent chips from hitting employees.
    • Do not stand in front of the feed table when the chipper is running.
    • Check material to be fed to ensure that it is free of metal and other foreign objects.
    • Use proper locking pins to immobilize the disc cutting wheel when attempting to clear a clogged chipper chute or changing chipper blades.
    • Train employees to shut down and lock out chippers before performing any maintenance and when machines are awaiting repair. Block the tires after detaching the machine from a towing vehicle and ensure the tires are blocked before operating. Post warning signs to keep the public a safe distance from chipping area.

Woodchipper manufacturers have introduced a variety of engineering controls designed to increase the safety of these machines. They include, feed tray extensions, rubber curtains in front of the infeed chute, feed control bars that stop or reverse feed rollers, pressure-sensitive bottom feed stop bars, panic bars that stop the hydraulic system that operates the feed rollers, and emergency pull ropes that allow operators to reverse feed rollers. Do not be tempted to speed productivity by disengaging or tampering with any of these safety devices. Remember, however, that engineering controls are never a substitute for safe work practices and common-sense precautions.

The ORFA encourages all members with this type of equipment to ensure that all devices are working properly and that all workers are properly trained before using the unit. Having detailed policy and procedures surrounding this equipment is also an essential part of worker safety. It is reasonable to expect that health and safety inspectors will be focusing on the use of this equipment as part of the recent fatality.