Stihl MSA 220.0 T Instruction Manual page 23

7 Kickback and Other Reactive Forces
– must be equipped with at least two devices to reduce the
risk of kickback injury, such as a chain brake, low kickback
chain, reduced kickback bar, etc.
The computer-derived angles for electric chain saws are
measured by applying a computer program to test results
from a kickback test machine.
WARNING
￭ Compliance with the chain saw kickback standards does
not mean that the bar and chain will rotate at most 25° in
a real life kickback.
￭ The computer-derived angles of the chain saw standards
may bear no relationship to actual kickback bar rotation
angles that may occur in a real life cutting situation.
￭ Devices designed to reduce the risk of kickback injuries
may lose some of their effectiveness when they are no
longer in their original condition, especially if they have
been improperly maintained.
– Read and follow the safety precautions and
instructions in this manual.
– When working, always position the chain saw such
that your body is clear of the cutting attachment and
outside of the cutting plane.
– Follow the maintenance and service instructions in
this manual.
￭ For the chain saw to meet the chain saw kickback
standards, use only the following cutting attachments:
– Compliant bar and chain combinations listed in
Combinations of Guide Bars and Saw Chains,
@ 28;
– Other replacement bar and chain combinations
marked in accordance with the standards for use on
the chain saw.
7.2.3 Devices for Reducing the Risk of Kickback Injury
The STIHL Quickstop chain brake and STIHL's green-
labeled, reduced kickback bars and green-labeled, low
kickback chains are designed to reduce the risk of kickback
injury.
0458-007-8601-A
1. STIHL Quickstop Chain Brake
There are two mechanisms for activating the chain brake if
it is in a properly maintained condition:
– Manual Activation: If a kickback occurs, the chain saw
moves upwards toward the user in a rotating motion
around the front handle. The brake is designed to engage
if the left hand contacts the front hand guard, which is the
activation lever for the brake, and pushes it forward.
– Inertia Activation: All STIHL chain saws are equipped with
an inertia Quickstop chain brake. If the kickback impulse
is strong enough, this alone is sufficient to engage the
brake, even without the operator's hand contacting the
front hand guard.
WARNING
￭ To reduce the risk of kickback injury:
– Never use a saw if the chain brake does not function
properly.
– When in doubt, take the saw to an authorized STIHL
servicing dealer for inspection and/or repair.
– Do not use the saw until the problem has been
corrected.
￭ In a kickback situation, the front hand guard helps protect
your left hand from contacting the chain. Removal of the
front hand guard on a chain saw equipped with a
English
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