-
What happened?
A chain saw operator used an unconventional cutting technique to fell a 31 metre (102 feet) tall tree with an abnormal root system.
During felling, a group of co-workers were at the edge of an exclusion zone, 60 metres away (2 x tree height).
Tree #1 fell 26.5 metres (90 feet) off target, struck tree #2b and started a domino effect. Tree #2b then fell and struck tree #3, which fell in the direction of the co-workers.
One of the workers located in the perceived safe zone was struck in the head and killed.
-
Why did it happen?
Cutting technique:
- Complex tree shape meant non-standard cutting technique used.
- Front and back cuts did not penetrate core of tree.
- Wedges were not used to influence direction of fall.
Tree felling
- Did not adequately account for ‘domino effect’ hazards.
- Exclusion zone or safe rest area not adequately established.
Work site plan
- No risk assessment performed.
-
What did they learn?
Always establish an exclusion zone, safe egress and/or escape route. Include these in work plans.
Ensure that all workers:
- understand mitigating/protective measures prior to tree felling.
- are aware of each other’s position.
Ensure that chain saw operator:
- understands reactive forces – pulling, pushing and kickback.
- maintains their position out of the cutting line.
-
Ask yourself or your crew
Were you aware this could happen?
How is the exclusion zone established? Where is it documented?
How do YOU determine felling direction? Who verifies the expected fall line?
Have overhead impacts been identified?
What can influence the fall direction? How?
Is safe egress planned? Are emergency contacts known?
Did YOU participate in the hazard analysis? Do you understand the mitigating/protective measures?
Add to homescreen
Content name
Select existing category:
Content name
New collection
Edit collection
What happened?
A chain saw operator used an unconventional cutting technique to fell a 31 metre (102 feet) tall tree with an abnormal root system.
During felling, a group of co-workers were at the edge of an exclusion zone, 60 metres away (2 x tree height).
Tree #1 fell 26.5 metres (90 feet) off target, struck tree #2b and started a domino effect. Tree #2b then fell and struck tree #3, which fell in the direction of the co-workers.
One of the workers located in the perceived safe zone was struck in the head and killed.
Why did it happen?
Cutting technique:
- Complex tree shape meant non-standard cutting technique used.
- Front and back cuts did not penetrate core of tree.
- Wedges were not used to influence direction of fall.
Tree felling
- Did not adequately account for ‘domino effect’ hazards.
- Exclusion zone or safe rest area not adequately established.
Work site plan
- No risk assessment performed.
What did they learn?
Always establish an exclusion zone, safe egress and/or escape route. Include these in work plans.
Ensure that all workers:
- understand mitigating/protective measures prior to tree felling.
- are aware of each other’s position.
Ensure that chain saw operator:
- understands reactive forces – pulling, pushing and kickback.
- maintains their position out of the cutting line.
Ask yourself or your crew
Were you aware this could happen?
How is the exclusion zone established? Where is it documented?
How do YOU determine felling direction? Who verifies the expected fall line?
Have overhead impacts been identified?
What can influence the fall direction? How?
Is safe egress planned? Are emergency contacts known?
Did YOU participate in the hazard analysis? Do you understand the mitigating/protective measures?
A worker died during a tree felling activity. The exclusion zone/safe rest area was not adequately established and the ‘domino effect’ hazard was not identified before work commenced.
