MASS MASS Test Rigging and Slings 2 — Questions and Answers
Question 1: What effect does a narrow sling angle (less than 30°) have on the tension in each leg of a multi-leg sling?
- It reduces tension in each leg
- It has no effect on individual leg tension
- It greatly increases tension in each leg (Correct answer)
- It balances the load more evenly
Correct answer: It greatly increases tension in each leg
Narrow sling angles dramatically increase the tension in each leg, potentially exceeding the sling's rated capacity even for a moderate load.
Question 2: Which type of hitch provides the least security because the load can tip or slide?
- Basket hitch
- Choker hitch
- Vertical hitch (Correct answer)
- Double-wrap choker hitch
Correct answer: Vertical hitch
A vertical hitch is the least secure because the load is only supported from above and can tip, rotate, or slide off the hook.
Question 3: What should a rigger check on a shackle before use?
- The color and finish only
- The pin is fully seated, moused, and the WLL is legible (Correct answer)
- Only the outer body for cracks
- Whether it matches the hook shape
Correct answer: The pin is fully seated, moused, and the WLL is legible
Riggers must verify the shackle pin is fully threaded and secured (moused), and confirm the Working Load Limit marking is readable.
Question 4: When using a choker hitch, how does the load capacity compare to the sling's vertical rated capacity?
- It is equal to the vertical capacity
- It is approximately 75-80% of the vertical capacity (Correct answer)
- It doubles the vertical capacity
- It is only 25% of the vertical capacity
Correct answer: It is approximately 75-80% of the vertical capacity
A choker hitch reduces the sling's effective capacity to approximately 75-80% of its vertical rating due to the angle stress at the choke point.
Question 5: What is the purpose of a tag line during a rigging operation?
- To attach the load to the crane hook
- To control load swing and rotation without direct contact (Correct answer)
- To measure the load weight
- To serve as a secondary lifting line
Correct answer: To control load swing and rotation without direct contact
Tag lines allow workers to guide and control a suspended load's rotation and movement without standing under or in direct contact with the load.
Question 6: Under OSHA 29 CFR 1926.251, who is responsible for inspecting rigging equipment before each use?
- The crane operator only
- The site safety officer
- A competent person (Correct answer)
- The rigging manufacturer's representative
Correct answer: A competent person
OSHA requires that rigging equipment be inspected before each use by a competent person who can identify unsafe conditions.
MASS MASS Test Rigging and Slings 2
What effect does a narrow sling angle (less than 30°) have on the tension in each leg of a multi-leg sling?