Chapter 15

Ropes and Knots

Introduction

• Rope is one of the most important and routinely used tools in the fire service • In this chapter, you will learn: – How to select the proper rope – The proper uses of rope in fire service – The essential skill of knot tying – How to properly inspect, maintain, and store rope 15.2

Rope Materials and Their Characteristics

• Constructed of a wide variety of materials • Each material has different characteristics • Earliest ropes were made of natural materials • The fire service has re-examined the type of rope materials being utilized as

life safety lines

15.3

Natural Materials

• Materials that fall into this category – Manila, sisal, and cotton • Share same poor characteristics with regard to: – Rot – Mildew – Abrasion resistance – Natural deterioration – Low shock load absorption capability 15.4

Figure 15-2 Type 1 manila rope.

15.5

Synthetic Materials

• Primary synthetic materials utilized: – Nylon – Polypropylene – Polyethylene – Polyester • Today, ropes made of these are the rule rather than the exception • High strength-to-weight ratio 15.6

Figure 15-6 Brightly colored polyethylene rope floating on water.

15.7

Construction Methods and Their Characteristics

• Natural fiber ropes dominating fire service were constructed using laid method • Modern ropes utilize a number of different construction techniques • Two broad categories: – Static – Dynamic 15.8

Laid (Twisted)

• Most common type of construction for natural fiber ropes • Formed by twisting individual fibers together to form strands or bundles • Tends to accentuate spinning and twisting • Advantage is that all fibers are exposed – Easy to inspect – Exposed fibers also susceptible to damage 15.9

Figure 15-7 Example of laid construction method.

15.10

Braided

• Utilized predominantly with synthetic fibers • Formed by weaving small bundles of fibers together, much the same as braided hair • Smooth to touch, high flexibility • Does not accentuate spinning • Every fiber exposed to abrasion, sunlight, and physical damage 15.11

Braid-on-Braid

• Formed by braiding a sheath over a smaller braided core • Ropes of this kind are quite dynamic • Soft sheath more susceptible to damage from abrasion Figure 15-9 Example of braid-on-braid construction method.

15.12

Kernmantle

• Kern is a derivative of the term kernel • Mantle is defined as “anything that cloaks, envelops, covers, or conceals” • Kern carries vast majority of load • Can be dynamic or static depending on configuration of fibers of kern • Quite resistant to abrasion 15.13

Figure 15-10 Example of kernmantle construction method with the outer kern cut and pulled back at the end, showing the inner mantle section.

15.14

Primary Uses

• Fire service utilizes ropes on a regular basis • Operations divided into two classifications: – Utility – Safety • Firefighter should be familiar with department standard rope use 15.15

Utility

• Rope used for utility purposes has no governing standards • Firefighters must take extra precautions when using

utility rope

• Firefighters should become familiar with common uses within their own department 15.16

Firefighting and Rescue Uses

• Ropes for structural search and rescue guide ropes do not fall into category of life safety ropes • Ropes, harnesses, and hardware utilized anywhere there will be life supported must comply with NFPA 1983 • NFPA 1983 categorizes life safety ropes as: – Light-use – General-use • NFPA 1983 also sets tensile strength requirements for each 15.17

Fire Service Knots

• Each service will have preferred methods and knots • Consult local protocol, policies or SOPs to find which knots expected for various situations • Some knots introduced with switch to synthetic fibers 15.18

Terms Used for Rope and Knots

• Three separate and distinct parts of a rope: – Working end – Standing part – Running end • Firefighters need to know terms used to describe elements combined to form knots 15.19

Figure 15-12 The three parts of a rope: working end, standing part, and running end.

15.20

Figure 15-13 Left to right: a round turn, a bight, and a loop. Take the loose end of the working end after tying the primary knot, and secure it by making a round turn around the standing knot and bringing the loose end through. Make a round turn in the standing portion of the rope, and slide the round turn down over the object being hoisted.

15.21

Knots

•

Dressing:

make sure parts of the knot are lying in the proper orientation to other parts •

Setting:

make sure knot is snug in all directions • Most commonly used: – Half hitch and overhand (safety) knot – Clove hitch – Becket bend and double becket bend – Bowline knot and figure eight knots – Rescue knot and water knot 15.22

(A) (B) Figure 15-14 (A) A loose and sloppy knot. (B) A knot properly dressed and set.

15.23

Inspection

• All ropes must be inspected and properly maintained • Inspections should be a matter of department policy • Life safety rope found damaged must be removed from service • Ropes should be inspected along their entire length 15.24

Figure 15-16 It is very important that rope is inspected as it is being put back into a rope bag.

15.25

Laid (Twisted)

• Firefighters should look and feel for: – Foreign matter – Slippery spots – Voids in center fibers – Stiff or hard spots and soft spots • Laid ropes should be untwisted at random intervals to inspect between strands 15.26

Figure 15-18 It is important to twist apart a laid rope to inspect between strands.

15.27

Braided

• Should be visually and tactilely inspected as well • Inspecting inside is not possible • All strands appear on the surface somewhere along the rope 15.28

Braid-on-Braid

• When inspecting braid-on-braid rope, there is no way to see the inside braided rope • Pay attention to tactile inspection – Watch and feel for damage • Outside braid will sometimes slip over the inner braid causing the rope to invert – Immediately remove from service • Outside braid represents 50 percent of strength 15.29

Kernmantle

• Cannot see kern portion – Represents 75 percent of total strength of rope • Tactile inspection is best and only way to discover damage to kern • Key is to search for a different feel – Flat spots, voids, bunches, stiffness, and limpness 15.30

Maintenance

• Maintenance of ropes is not difficult • Firefighter may be called on to assist with placing new rope into service • Carefully adhere to manufacturer's instructions 15.31

Cleaning

• Follow manufacturer's instructions • Brush dirt off natural materials; do not use water – Lose 50 percent of strength when wet – Do not regain strength when dry • Ropes manufactured from synthetic materials can be cleaned in a number of ways – Hand wash – Rope washer – Clothes washing machine 15.32

Figure 15 24 A kernmantle rope can also be “chained” and washed in a front-loading washing machine.

15.33

Drying

• Rope must be completely dried prior to storage • Different drying methods: – Lay flat to dry – Hang to dry • Use clothing dryer with extreme caution – Even a low temperature setting could surpass manufacturer’s recommendations 15.34

Storage

• Quick identification is important – Type – Length • Different material types, sizes, or colors of bags or tags can be used to differentiate • Each department needs to establish policy • Standard coiling • Utilization of special bags 15.35

Figure 15-27 The two most common methods of storing life safety ropes (bagged or coiled).

15.36

Rigging for Hoisting

• One of the primary uses of rope on emergency scene • Much smaller rope can be utilized • Can be stored bagged or coiled • Some departments have policies governing the use of

tag/guide lines

15.37

Specific Tools and Equipment

• Small figure eight on a bight with half hitch up handle is easiest and quickest way to hoist an ax • Pike poles should be hoisted point up • Hoselines can be hoisted charged or uncharged • Power tools have closed handles or support pieces • Ladders are hoisted on regular basis 15.38

Securing a Rope between Two Object s

• Need to secure a rope between two objects may arise at any emergency scene • Rope may be used as a barrier using one of two methods • Figure eight on a bight may be used to secure an anchor point 15.39

Lessons Learned

• Ropes have many uses • Fire service uses ropes on a regular basis • Experience is the most effective teacher • Firefighters are encouraged to practice the basics learned • Maintenance of rope is not difficult or complicated 15.40