Stihl MS 460 Instruction Manual page 18

The greater the force of the kickback
reaction, the more difficult it becomes for
the operator to control the saw. Many
factors influence the occurrence and
force of the kickback reaction. These
include chain speed, the speed at which
the bar and chain contact the object, the
angle of contact, the condition of the
chain and other factors.
The type of bar and saw chain you use
is an important factor in the occurrence
and force of the kickback reaction. Some
STIHL bar and chain types are designed
to reduce kickback forces. STIHL
recommends the use of reduced
kickback bars and low kickback chains
when your Rescue Saw is being used for
normal wood-cutting.
ANSI B 175.1-2000 chainsaw
kickback standard
Section 5.11 of ANSI standard
B 175.1-2000, sets certain performance
and design criteria related to chainsaw
kickback.
To comply with section 5.11 of ANSI
B 175.1-2000:
Rescue Saw
a) saws with a displacement of less
than 3.8 cubic inches (62 cm³).
– must, in their original condition,
meet a 45° computer derived
kickback angle when equipped with
certain cutting attachments.
– and 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.
b) saws with a displacement of
3.8 cubic inches (62 cm³) and above
– must be equipped with at least one
device designed to reduce the risk
of kickback injury such as a chain
brake, low kickback chain, reduced
kickback bar, etc.
The computer derived angles for saws
below 3.8 cubic inch (62 cm³)
displacement are measured by applying
a computer program to test results from
a kickback test machine.
English / USA
!
Warning!
The computer derived angles of § 5.11
of ANSI B 175.1-2000 may bear no
relationship to actual kickback bar
rotation angles that may occur in real life
cutting situations. In addition, features
designed to reduce kickback injuries
may lose some of their effectiveness
when they are no longer in their original
condition, especially if they have been
improperly maintained. Compliance with
§ 5.11 of ANSI B 175.1-2000 does not
automatic-ally mean that in a real life
kickback the bar and chain will rotate at
most 45°.
!
Warning!
In order for powerheads below 3.8 cubic
inch (62 cm³) displacement to comply
with the computed kickback angle
requirements of § 5.11 of ANSI B 175.1-
2000 use only the following cutting
attachments:
– bar and chain combinations listed
as complying in the "Specifications"
section of the Owner's Manual or
– other replacement bar and chain
combinations marked in
accordance with the standard for
use on the powerhead or
– replacement chain designated
"low kickback saw chain."
See the section on "Low kickback saw
chain and reduced kickback bars" in
these Safety Precautions.
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