end (also called a strap) or an endless sling (figure 4-37). When a sling is passed through its own bight or eye, or shackled or hooked to its own standing part, so that it tightens around the load like a lasso when the load is lifted, the sling is said to be choked, or it may be called a choker, as shown in figures 4-36 and 4-37. A two-legged sling that supports the load at two points is called a bridle, as shown in figure 4-38.
The following safety rules must be given to all hands engaged in hooking on. They must be strictly observed.
The person in charge of hooking on must know the safe working load of the rig and the weight of every load to be hoisted. The hoisting of any load heavier than the safe working load of the rig is absolutely prohibited.
When a cylindrical metal object, such as a length of pipe, a gas cylinder, or the like, is hoisted in a choker bridle, each leg of the bridle should be given a round turn around the load before it is hooked or shackled to its own part or have a spreader bar placed between the legs. The purpose of this is to ensure that the legs of the bridle will not slide together along the load, thereby upsetting the balance and possibly dumping the load.
The point of strain on a hook must never be at or near the point of the hook.
Before the hoist signal is given, the person in charge must be sure that the load will balance evenly in the sling.
Before the hoist signal is given, the person in charge should be sure that the lead of the whip or falls is vertical. If it is not, the load will take a swing as it leaves the deck or ground.
As the load leaves the deck or ground, the person in charge must watch carefully for kinked or fouled falls or slings. If any are observed, the load must be lowered at once for clearing.
Tag lines must be used to guide and steady a load when there is a possibility that the load might get out of control.
Before any load is hoisted, it must be inspected carefully for loose parts or objects that might drop as the load goes up.
All personnel must be cleared from and kept out of any area that is under a suspended load, or over which a suspended load may pass.
Never walk or run under a suspended load.
Loads must not be placed and left at any point closer than 4 feet 8 inches from the nearest rail
Figure 4-37. - Ways of hitching on straps.
Figure 4-38. - Bridles.
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