| 1. |
Which one of the following should be considered for safe rigging? |
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the weight of the load and rigging hardware |
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the capacity of the hoisting device |
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the working load limit of the hoisting rope, slings, and hardware. |
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All of the above |
| 2. |
The followings can do effect hoisting safety:
- Working Load Limit (WLL) not known.
- Defective components.
- Questionable equipment.
- Hazardous wind conditions.
- Weather conditions.
- Electrical contact.
- Hoist line not plumb.
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True |
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False |
| 3. |
There are countless situations where the rigger will be required to tie a safe and reliable knot or hitch in a fiber rope as part of the rigging operation. Fastening a hook, making eyes for slings, and tying on a tagline are a few of these situations. |
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True |
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False |
| 4. |
Inspect fibre rope regularly and before each use. Any estimate of its capacity should be based on the portion of rope showing _________________. |
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The least deterioration |
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The most deterioration |
| 5. |
Minimum breaking strength (MBS) is the force at which a component __________. The MBS is determined by the manufacturer, who also builds in a margin of safety called a design factor (DF). Together, this allows them to assign a working load limit (WLL) to the component. For example, if a chain is manufactured with an MBS of 3,000 pounds and a DF of 3, the WLL of the chain will be 1/3 that of the MBS.
3,000 lb (MBS) ÷ 3 (DF) = 1,000 lb (WLL) |
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May fail |
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May not fail |
| 6. |
In addition, if you know the working load (WL) of an object to be hoisted and the appropriate SF, you can calculate the required capacity (i.e., MBS) of a component used to hoist that object. For example, a hoist rope used to lift a 250 pound load (WL) must have an SF of 5 (as per O. Reg. 213/91, s. 172 (1)(d)). This means that the rope must have an MBS of at least five times the weight of the load, which is 1,250 lb.
250 pounds (WL) x 5 (SF) = 1,250 pounds (MBS) |
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True |
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False |
| 7. |
Wire ropes that are supplied as rigging on cranes must have the following design factors:
- live or running ropes that wind on drums or pass over sheaves
– 3.5 to 1
– 5.0 to 1 when on a tower crane
- pendants or standing ropes
– 3.0 to 1
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True |
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False |
| 8. |
Which one of the followings are a must in a wire rope: |
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wire rope must be steel of the type, size, grade, and construction recommended by the |
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manufacturer of the crane |
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compatible with the sheaves and drum of the crane |
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lubricated to prevent corrosion and wear. |
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All of the above |
| 9. |
Figure 1 on page 33 of the document, displays the cross section view of a |
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Wire rope construction |
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Water crystallization on the windshield upon impact |
| 10. |
Corrosion is a very dangerous condition because it can develop inside the rope without being seen. Internal rusting will accelerate wear due to increased abrasion as wires rub against one another. When pitting is observed, consider replacing the rope. Noticeable rusting and broken wires near attachments are also causes for replacement. Corrosion can be minimized by keeping the rope well lubricated. |
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Keeping the rope well lubricated |
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Less usage of the rope. |
| 11. |
All steel ropes will stretch during initial periods of use. Called “constructional stretch”, this condition is permanent. It results when wires in the strands and strands in the rope seat themselves under load. Rope stretch can be recognized by increased lay length. Six-strand ropes will stretch about six inches per 100 feet of rope while eight-strand ropes stretch approximately 10 inches per 100 feet. Rope stretched by more than this amount must be replaced. |
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True |
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False |
| 12. |
Bird caging ( Figure 5) can be caused as a result of |
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The rope being twisted or by a sudden release of an overload |
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Using too much oil lubricating the rope. |
| 13. |
The Regulations for Construction Projects require that an inspection and maintenance program be implemented to ensure that rigging equipment is kept in safe condition. Procedures must ensure that inspection and maintenance have not only been carried out but have been duly recorded. |
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True |
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False |
| 14. |
In a pre-job check list, whoever requires that a crane be used-project engineer, site superintendent, foreperson, building owner, contractor, architect, or consultant ____________________________________________ . |
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Is as responsible for its safe operation as the operator |
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Is not responsible for the safe operation |
| 15. |
If a working area has not been adequately prepared for the crane, the operation will be unsafe, regardless of machine capacity or operator skill. Consider the following factors. (page 123 of document)
- Can the machine get onto the site? Is the access road adequately graded and compacted? Is the access ramp too steep?
- Will the machine have to travel over buried pipes, sewers, mains, etc., that might be crushed?
- Is there room for the crane to maneuver in its designated position on site? Is there room to erect or extend the boom? Can trucks hauling boom sections get into position and be unloaded safely? Is there enough room and timber blocking to store boom sections properly?
- Will an area be designated and roped off for use by the erection crew? Will it be large enough for components to be stacked, handled, and assembled without endangering other site personnel?
- Has the crane’s position been identified for every lift? What will the maximum operating radius be? Will there be at least two feet of clearance between the counterweight and nearest object? What obstacles or other hazards might be posed by existing buildings or structures?
- Are operating areas graded, compacted, and levelled? Are they away from shoring locations, excavations, slopes, trenches, embankments, etc., which could subside under machine weight and vibration? Are operating areas over cellars, buried pipes, mains, etc., that may collapse?
- Will clearance and visibility be problems where other cranes, hoists, or equipment will be operating? Will operators have a clear view of other equipment to avoid collisions and keep hoisting ropes and loads from fouling? Will operators be provided with direct communication to warn one another of impending danger? Will the overall lifting program be laid out, controlled, and prioritized by one person in contact with all operators and each rigging crew?
- Will crane operating areas be away from public traffic and access? Will signallers and warning signs be provided when crane operations may overlap with public areas? Has police cooperation been arranged to provide traffic and pedestrian control?
- Have operators been warned and have provisions been made to keep cranes from working within a boom’s length of powerlines without
a) shutting off power
b) having the powerlines insulated, or
c) providing signalers to warn the operator when any part of the crane or load nears the limits of approach specified by the Regulations for Construction Projects?
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True |
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False |
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