Chapter 16: Climbing and Working in Trees Flashcards
What should a climber do before climbing a tree?
inspect all safety equipment, inspect the tree itself for hazards, make all workers aware of potential hazards, plan where to tie in and how to work the tree ahead of time
personal protective equipment
PPE; personal safety gear such as hard hat, safety glasses/goggles, hearing protection, and leg protection including chaps; protective clothing (includes chain saw resistant pants or chaps)
climbing saddles
work-positioning harness designed for climbing trees; harness
harness
climbing saddle
snaps
connecting device used by tree climbers, primarily for connecting the climbing line to the saddle; used in securing the climbing line or lanyard; self-closing and locking and compatible with the type of D-ring attachment on the harness
climbing line
rope that meets specifications for use in tree climbing
lanyard
short rope equipped with carabiners, snaps, and/or eye splices; work-positioning lanyards are used for temporarily securing a climber in one place
carabiners
connecting device; oblong metal ring used in climbing and static rigging that is opened and closed by a spring-loaded gate; self closing and auto-locking requiring at least two separate actions to prepare the gate for opening
tensile strength
force at which a new piece of equipment or rope in testing fails in tension under a static load
What is the minimum tensile strength in the United States?
5,000 pounds
What makes climbing lines suitable for tree climbing?
identified by the manufacturer, adequate strength, wear, and stretch characteristics
What are signs of excessive wear on a rope?
cuts, puffs, abrasions, pulled or herniated fibers, changes in diameter (inconsistent), discoloration, and glazing (melting) of the fibers
work-positioning lanyards
lanyard used in climbing, often as a secondary means of attachment
Prusik loops
loop of rope used to form a Prusik hitch for climbing or rigging
split-tails
separate, short length of rope used to tie the friction hitch in a climbing system
3-strand
rope construction in which three strands are twisted together in a spiral pattern; relatively low strength and high elongation; relatively inexpensive
16-strand
for arborist ropes, a braided rope that has a 16-strand, load-bearing cover and a filler core that is not significant in load carrying; parallel core to keep the rope round and firm under load; strength is in the cover strands
24-strand
for arborist ropes, a braided rope that has a 24-strand cover and is available in double-braid or kernmantle construction
double braids
rope construction consisting of a braided rope within a braided rope, both of which carry part of the load; rope within a rope; core and cover are balanced and share the load almost equally
Characteristics of rope
strength, stretch, durability
12-strand rope
for arborist ropes, a braided rope consisting of 12 strands; most are coreless; two types of 12-strand construction: a tight braid (tightly woven, solid-braid, polyester blend 12 -strand line) that is not easily spliceable, used for climbing and (natural crotch-rigging) rigging lines; and a loose (loosely woven, hollow-braid, polyester 12-strand rope) easily spliceable braid, commonly used for slings but not appropriate for climbing or rigging
hollow-braid
rope construction consisting of a braided rope with no core
cycles to failure
number of times a rope or other piece of equipment can be used with a given load before mechanical failure; each cycle (one lift or drop for a rigging line) creates permanent damage in the rope and eventually the rope will fail
working-load limit
WLL; tensile strength divided by design factor; maximum load that should not be exceeded in a piece of equipment, rope, or rope assembly when performing its normal working function
design factor
factor by which the rated or minimum breaking strength of a rope or piece of equipment is divided by in determining its working-load limit; safety factor; tensile strength divided by the working-load limit
working end
end part of a rope used for rigging and climbing; in use
standing part
inactive part of a rope
hitch
type of knot made when a rope is secured around an object or its own standing part
bend
type of knot used to join two rope ends together
climbing hitch (friction hitch)
hitch used to secure a tree climber to the climbing line, which permits controlled ascent, descent, and work positioning
What design factor is commonly used for ropes?
10
knot
general term given for all knots, hitches, and bends
dressing of the knot
the aligning of the parts
setting of the knot
tightens the knot in place
tautline hitch
type of friction hitch used by climbers for fall protection during ascent, descent, and work positioning
Blake’s hitch
friction knot climbers use, sometimes in place of the tautline hitch or Prusik knot
How to get into and ascend a tree?
use the climbing line, use a ladder, use climbing spurs but only if the tree is to be removed
climbing spurs
sharp devices strapped to a climber’s lower legs to assist in climbing poles or trees being removed; also called spikes, gaffs, irons, hooks, or climbers; only used for removals and aerial rescues
throwline
thin, lightweight cord attached to a throwbag or throwing ball used to set climbing or rigging lines in trees; used to set a rope in the tree
body-thrust technique
method of ascending a tree using a climbing rope; place your feet high on the trunk of the tree, thrust your hips upward to create slack in the line, pulling the other side of the line down and holding the line while pushing the friction or climbing hitch upward and taking up the slack and keeping the line taut
secured footlock technique
method of footlocking in which the climber utilizes an additional means of securing against a fall
micropulley
small, light-duty pulley used in climbing operations; often used a knot tender
footlocking
method of ascending a rope by wrapping the rope around the feet; once a rope has been set, climb the rope and use the secured footlock technique
Prusik hitch
type of multi-wrapped friction hitch used in climbing and rigging; a common use is to attach the Prusik loop to the climbing line when footlocking; always keep your hands below the hitch
single rope technique
SRT; set of methods used to ascend (or descend) on a single rope, as opposed to the double rope commonly used in secured footlocking techniques or dynamic climbing systems
ascenders
piece of gear that enables a climber to ascend a rope; attached to the rope, it will grip in one direction (down) and slide in the other (up)
access line
second climbing line hung in a tree in case it is needed to reach a victim in an emergency; climbing line installed in a tree to gain access to, but not used to work in, the tree; left in contact with the ground for emergency access or descent
Where to tie in?
it is desirable to pick high, central locations in the tree; the higher up means the farther out you can move out on the limbs; the more vertical the climbing line the more secure you are
How big should the main branch be in the crotch that you are tying in to?
varies with species and wood strength, but at least 4” in diameter and in the union against the trunk
figure-8 knot
particular knot tied as a safety knot or stopper knot at the end of the line
stopper knot
knot, usually a figure-8 knot, tied in the end of a line or in the tail of a knot to prevent the end or tail from passing through the knot; prevents the end from going through the climbing hitch
pole pruner
long-handled tool used to make scissors-like small pruning cuts that cannot be reached with hand tools
pole saw
long-handled tool with pruning saw on the end
scabbard
protective sheath for a pruning saw (handsaw) or other tool
clove hitch
knot used to secure a rope to an object
slip knot
slipped overhand knot
aerial rescue
method of bringing an injured worker down from a tree or aerial lift device; process of safely bringing an injured or unconscious worker in a life-threatening situation to the ground
rescue kit
climbing gear and emergency equipment that should be set out on every jobsite and available to conduct an aerial rescue and apply first aid; contains equipment (not used for routine daily work) climbing line and saddle, lanyard, throwline, climbing spurs, pole pruner, sharp knife, and first-aid kit
rigging
method using ropes and hardware; in tree pruning or removal, to control or direct the descent of cut material or to handle heavy loads; with cranes, loaders, or other equipment to lift heavy loads
rigging points
placement in the tree (in a natural or false crotch) or any other point through which the load line passes to control rigging operations
friction devices
device used to take wraps in a load line to provide friction for controlled lowering or climbing
bollards
post on which wraps can be taken with a rope to tie it off or to provide friction for control
load line
rope used to lower a tree branch or segment that has been cut; lowering line
rigging line
rope, usually the load line, used in rigging operations
bend ratio
ratio of the diameter of a branch, sheave, or other object to the diameter of the rope that is wrapped around it
lowering devices
brand name of a piece of equipment that is attached to the tree base or other anchor in rigging; used to take wraps with the load lines to provide friction for controlled lowering of sections of a tree
shackles
U-shaped fitting with a pin running through it; clevis
screw links
connecting device with a threaded closure mechanism; used to secure equipment or tree sections in rigging operations; steel connecting links are usually the preferred choice in rigging
dynamic loading
forces created by a moving load; load that changes with time and motion
aluminum vs. steel
aluminum is preferred for climbing because it is light weight
steel has far better strength and fatigue properties
blocks
heavy-duty pulley used in rigging; designed for dynamic loading; casing enclosing one or more parallel pulleys
sheaves
inner fitting within a block or pulley over with the rope runs
rescue pulleys
light-duty pulley used in light rigging operations
rope sling
length of rope, usually with at least one eye splice, used to secure equipment or tree sections in rigging operations
webbing slings
length of sewn webbing, often formed into a loop, used as an attachment in rigging
bight
curve or arc in a rope between the working end and the standing part
bight
curve or arc in a rope between the working end and the standing part
half hitches
simple knot used to temporarily attach a line to an object; also used as a back up in combination with other knots
running bowline
bowline knot with the standing part of the line running through the loop; often used to tie off and control branches or tree sections that are to be removed; can be used when the desired tying point cannot be directly accessed by the worker
landing zone
predetermined area where cut branches or wood sections will be dropped or lowered from a tree
drop zone
predetermined area where cut branches or wood sections will be dropped or lowered from a tree
butt-tying
tying off a limb at the butt (larger) end for rigging
tip-tied
tying a line on the tip (brush) end of a branch to be removed
balanced
in rigging, a technique for lowering a limb without allowing either end to drop
tagline
rope used to control the swing of a limb being removed or to control the direction of fall of a tree or limb being removed
butt-hitching
method of lowering pieces when the rigging point is below the work, traditionally without the use of a block; a piece is tied above a cut and the line is run through a block or crotch below the cut; high shock-loading posibility
shock-loading
dynamic, sudden force placed on a rope or rigging apparatus when a moving load or piece is stopped
drop cut
branch-removal technique consisting of an undercut and then a top cut, usually made farther out on the branch, or with a chainsaw directly over the undercut
kerf
slit or cut made by a saw in a log; space created by a saw cut
snap cut
cutting technique in which offset, bypassing cuts are made so that a section can be broken off easily; cut slightly more than halfway through a section from the side, then cut from the opposite side about an inch or more offset from the first cut, the cuts will bypass but the fibers should hold and the remaining piece can be broken off manually
hinge cut
sequence of cuts used to control the direction of a limb being removed; topping cut when taking a vertical top out of a tree; employs a notch and back cut to form a hinge; swings the limb around rather than simple dropping the branch to the ground
notch
wedge cut into a log or tree for felling
back cut
cut made on a tree trunk or branch, opposite from and toward the notch, face cut, or undercut, to complete felling or branch removal
hinge
strip of uncut wood fibers created between the face cut or notch and the back cut that helps control direction in tree felling or limb removal; holding wood; “steers” the limb
