USING LINES AND SLINGS The safety of personnel involved in rigging and hoisting operations largely depends upon care and common sense. Equally important is the proper selection of lines and slings for safe and stable lifts.

INSPECTIONS The single most important operational check to be made on hoisting and rigging equipment is the line and rigging inspection. Such factors as abrasion, wear, fatigue, corrosion, and kinking are of great significance in determining usable life. The only way to determine the safety of a line, its life expectancy, and its load-carrying ability is by regularly inspecting every foot of its length. The main points to watch for are external wear and cutting, internal wear between the strands, and deterioration of the fibers.

FIBER LINES Fiber lines are made from either natural or synthetic fibers. The natural fibers come from plants and include manila, sisal, and hemp. The synthetic fibers include nylon, polypropylene, and the polyesters. The strength

Figure 1-1.- Removing line from a shipping coil.

of these lines depends on their size, the fiber used, and the type of stranding. Uncoiling Line New line is coiled, bound, and wrapped. The protective covering should not be removed until the line is to be used. This covering will protect the line during stowage and prevent tangling. To open, strip off the outer wrapping and look inside the coil for the end of the line. This should be at the bottom of the coil. If not, turn the coil over so that the end will be at the bottom, as shown in figure 1-1. Pull the end of the line up through the center of the coil. As the line comes up through the coil, it will unwind in a counterclockwise direction. Whipping Line The term whipping refers to the process of securing the ends of a line to prevent the strands from unraveling and the yarns from separating or fraying. Whippings are made from fine twine and will not increase the size of the line enough to prevent it from fitting the blocks or openings.

Figure 1-2 shows the steps to follow in applying a whipping. Make a loop in the end of the twine and place

Figure 1-2.- Proper way to apply a line whipping.

the loop at the end of the line, as shown in the figure. Wind the standing part around the line covering the loop of the whipping. Leave a small loop uncovered, as shown. Pass the remainder of the standing end up through the small loop and pull the dead end of the twine, thus pulling the small loop and the standing end back towards the end of the line underneath the whipping. Pull the dead end of the twine until the loop with the standing end reaches a point midway underneath the whipping. Trim both ends of the twine close up against the loops of the whipping. Before cutting a line, place two whippings on the line 1 or 2 inches apart and make the cut between the whippings. This will prevent the ends from unraveling after they are cut.

Stowing Line Before stowing a fiber line, you must take certain precautions to safeguard the line against deterioration. You should never stow a wet line. Always dry the line well before placing it in stowage. After a line has been used, you should coil it down in a clockwise direction (assuming it is a right-hand lay). Should the line be kinked from excessive turns, remove the kinks by the procedure known as "thorough footing." You do this by coiling the line down counterclockwise and then pulling the bottom end of the coil up and out the middle of the coil. If the line is free of kinks as it leaves the coil, make it up in the correct manner. If it is still kinked, repeat the process before making up the line for stowage. Choose your stowage space for line carefully. Line deteriorates rapidly if exposed to prolonged dampness. Furthermore, it is important for the stowage area to be dry, unheated, and well ventilated. To permit proper air circulation, you should either place the line in loose coils on a wood grating platform about 6 inches (15 cm) above the floor or hang the line in loose coils on a wooden peg. You should NEVER expose a line to lime, acids, or other chemicals, or even stow it in a room containing chemicals. Even the vapors may severely damage line. As a final precaution, avoid continually exposing line to sunlight. Excessive sunlight will also damage the line.

Strength of Fiber Line Overloading a line poses a serious threat to the safety of personnel, not to mention the heavy losses likely to result through damage to material. To avoid overloading, you must know the strength of the line you are working with. This involves three factors: breaking strength, safe working load, and safety factor.