WAC 296-54-563
Guying tail/lift trees. (1) Whenever a
tail/lift tree is within reach of the work area and the
rigging is placed on the tail/lift tree at a height greater
than five times the tree diameter (dbh), at least two guylines
must be used unless tree size and strength and rigging
position eliminate the need for guylines or employees must be
in the clear before the go-ahead signal is given.
(2) Guylines on tail/lift trees must not be anchored to
standing trees unless:
(a) There is no danger that the guyline anchor tree will
enter the work area;
(b) The guyline anchor tree is properly tied back; or
(c) Employees are in the clear of the guyline anchor
tree(s) before the go-ahead signal is given.
(3) When guylines are required, they must be positioned
according to Figure 16: Positioning Guylines in Back of Tree
and Figure 19: 4 Guyline Case - Tail/Lift Tree Guying as
follows:
(a) When the angle between the horizontal and skyline
coming into the tree (angle A in Figure 16) is less than the
angle between the horizontal and the skyline leaving the tree
towards the anchor point (angle B in Figure 16), the guylines
must be in back of the tail/lift tree as specified in Figure
19.
(b) If angle A is greater than angle B, then the guys
must be placed in front of the tail/lift tree. This situation
usually occurs when a tail/lift tree is used during downhill
yarding as shown below. Placing the guys on the uphill side
only helps to pull the tail/lift tree over uphill.
(c) If a suitable anchor is not available within a
specified shaded zone, two guylines may be used instead of one
guyline, provided a guyline is placed on either side of and as
near as possible to the affected shaded zone.
(4) Tail/lift trees must be supported by additional
guylines if necessary, to ensure the stability of the tree.
(5) Guylines for tail/lift trees may be made of synthetic
material and must be used according to the manufacturer's
recommendation.
[Statutory Authority: RCW 49.17.010, [49.17].040 and[49.17].050
. 99-17-117, § 296-54-563, filed 8/18/99,
effective 12/1/99. Statutory Authority: RCW 49.17.040,
49.17.050, 49.17.240, chapters 43.22 and 42.30 RCW. 80-11-057
(Order 80-15), § 296-54-563, filed 8/20/80. Statutory
Authority: RCW 49.17.040, 49.17.150 and 49.17.240. 79-10-081
(Order 79-14), § 296-54-563, filed 9/21/79.]