Stihl MSA 120 C Instruction Manual page 43

4 Safety Precautions
4.7.3 Felling
WARNING
■ Inexperienced users cannot assess the dan‐
gers of felling a tree. This can result in serious
or fatal injuries and damage to property.
► If you have any queries: Do not fell the tree
yourself.
■ A tree and branches can fall on bystanders or
objects during the felling operation. This can
result in serious or fatal injuries and damage
to property.
► Determine direction of fall so that the area
in which the tree falls is clear.
► Do not allow bystanders, children or ani‐
mals within 2.5 tree lengths of the felling
site.
► Remove broken or dead branches from the
tree crown before felling.
► If broken or dead branches cannot be
removed from the crown: Do not fell the
tree.
► Observe tree crown and crowns of neigh‐
boring trees and keep clear of falling
branches.
■ When the tree falls the trunk can break or
spring back in the direction of the user. This
can result in serious or fatal injuries.
► Plan an escape path sideways behind the
tree.
► Walk backwards along the escape path and
observe the falling tree.
► Do not walk backwards down slopes.
■ Obstacles in the work area and on the escape
path can hinder the user. The user may trip
and fall. This can result in serious or fatal inju‐
ries.
► Remove all obstacles from the work area
and escape path.
■ If you cut into or through the hinge, stabilizing
strap or holding strap too soon, the intended
direction of fall cannot be controlled or the tree
can fall prematurely. This can result in serious
or fatal injuries and damage to property.
► Do not cut into or through the hinge.
► Cut through the stabilizing strap or holding
strap last.
► If the tree begins to fall too soon: Abandon
the felling cut and retreat along the escape.
■ Kickback can occur if the rotating chain in the
upper quadrant of the bar nose makes contact
with a hard felling wedge and is suddenly
braked. This can result in serious or fatal inju‐
ries.
► Use aluminum or plastic felling wedges.
0458-716-9621-D
■ If the tree does not fall all the way to the
ground or gets caught on another tree, the
operator cannot finish the operation in a con‐
trolled manner.
► Stop the felling operation and use a cable
winch or suitable vehicle to pull the tree to
the ground.
4.8 Reactive Forces
4.8.1 Kickback
Kickback can be caused for the following rea‐
sons:
– The rotating saw chain in the upper quadrant
of the bar nose makes contact with a hard
object and is suddenly braked.
– The rotating saw chain is pinched at the bar
nose.
The chain brake cannot prevent kickback.
WARNING
If kickback occurs, the saw can be thrown up
■
in the direction of the operator. The operator
can lose control of the saw and be seriously or
fatally injured.
► Hold the saw firmly with both hands.
► Always keep your body out of the plane of
the cutting attachment.
► Operate the saw as described in this
instruction manual.
► Do not cut with the upper quadrant of the
bar nose.
► Always cut with a properly sharpened and
tensioned saw chain.
► Use a reduced kickback saw chain.
► Use a guide bar with a narrow radius nose.
English
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