Chapter 6 Ropes & Knots Flashcards
Types of Rope
- Life safety, used to support rescuers and victims
- Utility, used in any instance, excluding life safety
Life Safety rope
“rope dedicated solely for the purpose of supporting people during rescue, fire fighting, or other emergency operations, or training evolutions
Only block creal construction using continuis filament virgin fiber for load bearing elements is suitable for life saftey application.
NFPA 1983
Standard on Fire Service Life Safety Rope & System components.
Rope Manufactuer must supply info regarding, use criteria, inspection procedures, maintenance & retiring procedures.
Only block creal construction using continuis filament virgin fiber for load bearing elements is suitable for life saftey application.
Criteria to consider before life safety rope is reused
- Rope Hasnt been exposed to heat, not been visibly damaged, direct flame impingement, or abrasion
- Rope hasnt been subect to impact load, not been exposed to liquids, solids, gases, mists, or vaports if any chemical or material that can deteriorate rope
Rope Materials
- Natural Fiber (Utility only)
(Manila, sisal, Cotton) - Synthetic
- resistance to mildew & rotting, excelent strength, east to maintane
- Continues fibers running intire length
Rope Construction for life safety
- Dynamic (high stretch) rock climbing long falls, reduce shock of impact
- Disadvantage stretching while trying to raise and lower heavy loads.
- Static (low stretch) rope of choice for rescue, used for hauling, rescues rappelling, where no falls are likely to occur only very short distances
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Most Common types of construction
- Laid (twisted)
- Braided
- Braid on Braid
- Kernmantle
Laid (twisted)
- Generally 3 strands twisted together
- Susceptible to abrasions
- All 3 strands exposed at various points
Braided
Most are made of synthetic
- Uniformly intertwinning strands together (like hair)
- Subject to direct abrasion & damage
Braid on Braid
Very strong Core strenth 50% sheath 50%
- because its jacketed it confused with kernmantle
- Braided core & Sheath. Sheath has a herring bone pattern.
- Disadvantage, doesnt resist abrasion as well as kernmantle & sheath may slide along inner core
Kernmantle
Jacketed rope, composed of a braided covering of sheath ( mantle) over the main load bering strands (kern) Comes both static & Dynamic
- Core runs parrallel with the covering, increases strength, made of high strech fibers, most of total strength.
- Sheath, small amount of overall strength, absorbs most abrasions, Protects core.
Rope Maintenance
Inspecting after each use, visually & tactilely (by touch), for shards of glass, metal shaving, wood splinters, or foreign objects,
If any are found remove from servise
Inspecting laid rope
Soft, crusty, Stiff or Brittle spots, untwisted
Mildew does not necessarily indicate a problem. Fowl smell might indicate rotting ro mildew in manila rope
Inspecting Braided rope
Inspect for exterior damage (heat stress, nicks, cuts) excess of unusual fuzziness.
Inspecting Braid on Braid
Heat sears, nicks, cuts, sheath sliding on core.
If found cut the end & pull off excess material then sew the end.
Inspect for lumps that indicate core damage
Inspecting kernmantle
May be difficult
-Putting slight tension while feeling for lumps, depressions, or soft spots.
damage to outer sheath indicates probable damage to the core.
Inspect for irregulations in shape of weave, foul smells, discoloration, roughness, abrasions, fuzziness
Log Book
Helps to determine when rope should be retired
- Date of each use & inspection
- Keep in water proof envelope sewn in side of ropes storage bag
Cleaning ropes
- Natural fibers cannot be cleaned effectivley because water cannot be used. wipe or gently brush
- Continual exposure to wetting & drying, water weaken & damages the fibers
- Synthetic fibers Cool water & mild soap
Handwashing, special rope washer, regular clothes washer. Front loader with out plastic window.
Knots
are used to join or connect objects or to form loops
Running end
Part for hoisting, pulling or belaying
Working End
Part used in forming the knot also know as the (loose or bitter end)
Standing part
Part between the working & running end
Safety knots
single or doubly overhand knots
Elements of a knot
Rope stregth is reduced whenever it is bent
- Bight, formed when bending the rope back on its self while keeping sides parallel
- Loop, Crossing the side of the bight over the standing part
- Round turn, Consists of further bending one sode of a loop
Bight
Formed when bending the rope back on its self while keeping side parallel
Loop
Crossing the side of the bight over the standing part
Round Turn
Consists of further bending one side of a loop.