WORKING TECHNIQUES
28 – English
a) attach the rope around the rope eyelet on the rear of the
saw.
b) provide suitable karabiners to allow indirect (i.e. via the
strop) and direct attachment (i.e. at the attachment point
on the saw) of saw to the operators harness.
CAUTION! The belt eyelet is not dimensioned for use with
a so-called safety rope. Use the rope eyelet for this
purpose.
c) ensure the saw is securely attached when it is being
sent up to the operator.
d) ensure the saw is secured to the harness before it is
disconnected from the means of ascent.
The saw should only be attached to the recommended
attachment points on the harness. These may be at mid-
point (front or rear) or at the sides. Where possible
attaching the saw to centre rear mid-point will keep it clear
of climbing lines and support its weight centrally down the
operator’s spine.
When moving the saw from any attachment point to
another, operators should ensure it is secured in the new
position before releasing it from the previous attachment
point.
Using the chainsaw in the tree
An analysis of accidents with these saws during tree
service operations shows the primary cause as being
inappropriate one-handed use of the saw. In the vast
majority of accidents, operators fail to adopt a secure
work position witch allows them to hold both handles of
the saw. This results in an increased risk of injury due to:
•
not having a firm grip on the saw if it kicks back.
•
a lack of control of the saw such that it is more liable
to contact climbing lines and operators body
(particularly the left hand and arm)
•
loosing control from insecure work position resulting
in contact with the saw (unexpected movement during
operation of the saw)
Securing the work position for two-handed use
To allow the operator to hold the saw with both hands,
they should as general rule, aim for secure work position
where they are operating the saw at:
•
hip level when cutting horizontal sections.
•
solar plexus level when cutting vertical sections.
Where the operator is working close into vertical stems
with a low lateral forces on their work position, then a good
footing may be all that is needed to maintain a secure
work position. However as operators move away from the
stem, they will need to take steps to remove or counteract
the increasing lateral forces by, for example, a re-direct of
the main line via a supplementary anchor point or using
an adjustable strop direct from the harness to a
supplementary anchor point.
Gaining a good footing at the working position can be
assisted by use of a temporary foot stirrup created from
an endless sling.
Starting the saw in the tree , bucket truck or sky lift
The chain brake should always be engaged when
lowering a machine onto its strop. The operator should
always check that the battery is fully charged before
undertaking critical cuts.
One-hand use of the chainsaw
Operators should never use a chain saw onehanded.
Operators should never:
•
cut with the kickback zone at the tip of the chainsaw
guide bar
•
‘hold and cut’ sections.
•
attempt to catch falling sections.
•
Cut in the tree when he/she is only secured with one
rope, always use 2 secured lines.
•
check condition of harness, belt and ropes at regular
frequent intervals.
Freeing a trapped saw
If the saw should become trapped during cutting,
operators should:
•
switch off the saw and attach it securely to the tree
inboard (i.e. towards the truck side) of the cut or to a
separate tool line.
•
pull the saw from the kerf whilst lifting the branch as
necessary.
•
if necessary, use a handsaw or second chain saw to
release the trapped saw by cutting a minimum of 30
cm away from the trapped saw.
Whether a handsaw or a chainsaw is used to free a stuck
saw, the release cuts should always be outboard (toward
the tips of the branch), in order to prevent the saw being
taken with the section and further complicating the
situation.
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