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Text from
the OSHA Logging Preamble
Section V: Summary and
Explanation of the Final Standard
Paragraph (h) Tree Harvesting
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Yarding
Paragraph (h)(5) specifies various work practice requirements covering yarding
activities. Paragraph (h)(5)(i) of the final rule requires that logs not be moved until
each employee is in the clear. This provision has been adopted from the proposed rule.
Movement of logs when employees are in the immediate area can result in an injury to those
employees.
According to the WIR survey, almost 20 percent of employees injured were involved in
yarding operations at the time of their accident (Ex. 2-1). When a log is moved on uneven,
unimproved terrain, the exact path that the log will follow is impossible to predict. When
they are being moved, logs may roll over, or the loose end of a log may flip back and
forth (fishtail). Movement in an unanticipated direction can cause the log to strike an
employee, causing serious injury. OSHA has included this requirement in the final rule to
ensure that when logs are moved, all personnel must be safely positioned and not exposed
to a hazard. OSHA did not receive any comments opposing this provision.
Paragraph (h)(5)(ii) of the final rule requires that each choker be hooked and unhooked
from the uphill side or end of the tree or log when rolling or sliding is reasonably
foreseeable, unless the employer demonstrates that it is not feasible in the particular
situation to hook or unhook the choker from the uphill side. This provision also requires
that when the choker is hooked or unhooked from the downhill side, the log shall be
securely blocked or chocked to prevent rolling or swinging. The proposed rule also
specified that chokers be hooked and unhooked from the uphill side when feasible unless
the log is securely blocked to prevent rolling or swinging. The 1978 ANSI logging standard
also contained a similar requirement. There were no comments opposing this provision.
Employees who hook and unhook chokers on sloping terrains face the same hazard of
rolling or sliding logs as do fellers, buckers, limbers and other employees. According to
the WIR survey, 19 percent of the injuries reported occurred during choker setting,
hooking and unhooking (Ex. 2-1). In addition, the WIR survey indicates that nearly
three-fifths of all workers injured were working on moderate to steep terrain at the time
of their accidents. The final rule makes clear OSHA's intention that all hooking and
unhooking of chokers must be from the uphill side or end when rolling or sliding is
reasonably foreseeable. This is the only work location in which it can be assured that an
employee will not be hurt by a rolling or sliding tree. For this reason, hooking or
unhooking chokers from the downhill side is not permitted simply because the tree has been
secured with a chock. Rather, the employer must evaluate on a case-by-case basis whether
it is possible to hook or unhook from the uphill side. Only when the employer has
demonstrated that hooking or unhooking the choker from the uphill side or end is not
feasible in the particular situation is hooking or unhooking the choker from the down hill
side permitted.
Paragraph (h)(5)(iii) of the final rule requires that each choker be positioned near
the end of the log or tree length. This provision was adopted from the proposed rule.
There were no comments opposing this provision.
Positioning a choker at the end of the log ensures that the log is moved along its
longitudinal axis. Hooking up and skidding a tree or log requires much less energy than
trying to move the tree or log sideways. If an employee were to try to move a tree or log
by dragging it sideways (perpendicular to its longitudinal axis) the tree or log could
become wedged behind another tree, a rock, or a stump, causing the premature failure of
the haulage equipment and the possibility of employee injury if the restraint were to
suddenly break or release the tree or log. Because of these hazards, the usual practice in
non-cable yarding is to skid or drag a tree or log when moving it. When trees or logs are
skidded, the choker is hooked to the end of the tree or log and it is pulled along the
ground.
Paragraph (h)(5)(iv) of the final rule requires that each machine be positioned during
winching so the machine and winch are operated within their design limits. The proposed
rule required that the machine be positioned so that the winch line is as near in
alignment as possible with the long axis of the machine, unless the machine is designed to
be used under different conditions of alignment.
One commenter opposed the proposed provision for several reasons (Ex. 5-34). First, the
commenter said that some machines, such as cats and skidders, are designed to sustain
winching strain from a much broader angle than straight behind the machine, therefore, the
proposed provision was needlessly restrictive if the machine is being operated within its
rated capacity. Second, the commenter said it was not possible to comply with the
provision in many situations. For example, the commenter said arches are normally equipped
with fairleads and grapples that swing sideways out of alignment with the long axis of the
machine. Third, the commenter said the provision would create a greater hazard when
winching is conducted on very steep terrain. In such cases, the commenter said, it is more
important that the machine be positioned to assure maximum stability rather than
positioning the machine relative to the log being winched.
OSHA recognizes that exact alignment is not always possible in the woods. OSHA also
recognizes that a machine may have a winch mounted on it that may work off the side or
front of the machine, and that aligning the winch line with the long axis of the machine
may not be the safest manner to operate the winch.
OSHA agrees with this commenter that what is most important is that the design limits
of the machine and winch not be exceeded. Therefore, OSHA has revised the wording of this
provision to ensure that winching operations conducted with machines are performed within
the design limitations of the machines.
Paragraph (h)(5)(v) of the final rule requires that no line be moved unless the yarder
operator has clearly received and understood the signal to do so. This provision also
requires that when the yarder operator is in doubt, the operator must repeat the signal
and wait for a confirming signal before moving any line. This provision has been adopted
from the proposed rule. A similar provision also was contained in the 1978 ANSI logging
standard and in various State logging standards (Ex. 2-14, 2-18, 2-20, 38J). OSHA did not
receive any comments opposing this provision.
OSHA believes that adequate communication is necessary for the safe movement of trees
and logs. If the yarder operator begins moving the tree or log before the choker setter or
chaser has moved to a safe location, the choker setter or chaser could be injured if
struck or caught by a yarding line, carriage, or choker, or by the tree or log.
Paragraph (h)(5)(vi) of the final rule requires that the load shall not exceed the
rated capacity of the pallet or other carrier. This provision has been adopted from the
proposed rule. OSHA did not receive any comments opposing this provision. This provision
is an outgrowth of the requirement that the rated capacity of machines shall not be
exceeded. In order to prevent machines from rollovers and tipovers, it is also essential
that loads on trailers not exceed the maximum capacity the trailer was designed to carry
and the machine was designed to transport. If loads exceed the maximum capacity, the
machine operator will be at greater risk of rollover or tipover. As discussed above, a
significant number of fatalities have occurred in the logging industry due to rollover
accidents. NIOSH reported that 80 logging employees were killed in machine rollover
accidents from 1980-85 (Ex. 5-42). The State of Washington reported that 12 logging
employees were killed in rollover accidents from 1977-83 (Ex. 4-129).
Paragraph (h)(5)(vii) of the final rule requires that towed equipment must be attached
to the machine or vehicle in such a manner as to allow a 90 degree turn, to prevent
overrunning of the towing machine or vehicle and to assure that the operator is always in
control of the towed equipment. Towed equipment includes but is not limited to skid pans,
pallets, arches and trailers. This provision parallels the proposed requirement. There
were no comments opposing this provision.
OSHA's intention in this provision is two-fold. First, OSHA believes this provision is
necessary to help reduce the potential for rollover of vehicles or machines that are
moving equipment to various work sites. For example, a trailer carrying a maximum load
could tip over or roll over and cause the towing machine or vehicle to roll over if the
loaded trailer cannot make a full 90 degree turn. Second, this provision is necessary to
help assure that material handling equipment is not overloaded. This provision must be
viewed in conjunction with the requirement that loads must not exceed the rated capacity
of the trailer or other carrier on which it is being towed. For example, when towed
equipment exceeds the rated capacity of the towing trailer, it may overrun the towing
machine or vehicle. When the rate capacity of the trailer is exceeded there is an
increased likelihood that the operator may lose control over the towed equipment and an
accident could result.
Paragraph (h)(5)(viii) of the final rule requires that each yarding machine or vehicle,
including its load, must be operated with safe clearance from all obstructions. This
provision has been adopted from the proposed rule. There were no comments opposing this
requirement.
Paragraph (h)(5)(ix) of the final rule requires that each yarded tree must be placed in
a location that does not create a hazard for an employee and be placed in an orderly
manner so that the trees are stable before other work, such as bucking or limbing, is
commenced. The proposed rule required that trees yarded for bucking shall be safely
located and stable before bucking is commenced. There were no comments opposing this
provision.
In the final rule, OSHA has expanded this provision to provide that no work is
commenced until yarded trees are stabilized and safely located. OSHA believes it is
necessary to apply this provision to all work done in the area of yarded trees. The WIR
survey indicates that the single greatest cause of accidents in the logging industry is
being injured by a tree, log or limb and a significant number of employees were injured
performing bucking and limbing (Ex. 2-1). If operations, such as bucking or limbing, are
located too close to other work operations, unsuspecting loggers could be injured by a
rolling log. Moreover, if yarded trees or stacks of trees are not stabilized, loggers
performing work activities involving these trees could be at substantial risk of injury if
the unstabilized trees move, shift or roll.
In the final rule, OSHA has not retained two proposed requirements from this paragraph.
The first would have required the examination of spar trees for defects before they are
rigged. This provision has been deleted because it relates to the construction of cable
yarding systems that is not covered by the final rule.
The second provision would have required unstable trees and spars to be guyed to ensure
stability. Some commenters said that requiring employees to climb on and rig unstable
trees presents a greater hazard than does felling an unguyed tree (Ex. 5-17, 5-21). The
weight of the climber and his rigging gear could cause the tree to break off and fall
over, resulting in serious injury or death to the climber. OSHA has addressed in other
ways the hazards associated with danger trees through other practice requirements. For
example, the final rule requires danger trees to be felled or removed before any work can
be commenced in the area.
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