In a sawmill outside Ontario, a log had just passed through the slasher, where it was cut to length, when it fell from the wood transfer conveyor and became jammed on top of a vertical rubber deflector panel at the end of the drop chute. A worker arrived with a chainsaw to cut the log free. While cutting, the chainsaw kicked back and struck the worker in the neck, fatally injuring him.
Why did it happen?
Chainsaw kickback occurs when the chain is suddenly forced to a stop and the energy from the chain is transferred to the saw itself in the opposite direction. In this case, a violent kickback occurred when the saw’s chain came into contact with the rubber deflector panel as it was cutting the jammed log.
How can it be prevented?
Logs can get crossed and jam up almost anywhere in the sawmill’s transfer system. Chainsaws are sometimes used to clear the jammed log. Depending on the size of the log and the position of the jam-up, options other than chainsaw use should be considered to clear the jam. Such options include the use of pike poles, pry bars, come-alongs or electric hoists.
If there is no alternative to using a chainsaw to clear the jam, the chainsaw operator should carefullyenter the area to examine the situation and determine the cuts that need to be made. Possible hazards such as compression and tension problems should be identified in order to decide where and how to cut, keeping in mind any obstacles that might be near the cut area. The chainsaw operator should always ensure that the saw’s chain brake is in optimum condition.
As the cut is being made, the chainsaw operator should ensure that the cut area is not exposing the tip of the bar and cutting chain to any other nearby objects (pieces of equipment, deflector panel, conveyor, concrete floor or wall) that could result in a kickback. The cut should be performed calmly and carefully, avoiding awkward postures that will increase the likelihood of muscle fatigue. If necessary, the chainsaw operator should stop and rest for a moment.
WSN has developed a training course, Safe Chainsaw Use in Forestry Mills, that describes the most common and widely accepted techniques for dealing with jam-ups in sawmills based on a review of industry best practices.