Idaho Rigger Qualification Examination
Advanced 100-Question Practice Exam
2026 | Questions & Answers with
Detailed Rationales | Complete Exam
Prep & Study Guide
1. What is the primary purpose of determining the working load limit (WLL) of
a sling before making a lift?
A. To determine the crane's maximum radius
B. To ensure the sling is not loaded beyond its rated capacity
C. To determine the load's center of gravity
D. To determine the operator's required certification
Answer: B. To ensure the sling is not loaded beyond its rated capacity
Rationale: The WLL establishes the maximum permitted load for the sling under
specified conditions. Exceeding it can cause sling failure, dropped loads, and
serious injuries.
2. A rigger is preparing a four-leg bridle sling, but the load is supported
primarily by only two legs because of uneven geometry. What is the safest
approach?
, A. Assume all four legs share the load equally
B. Increase the crane capacity
C. Determine the actual load distribution before selecting the sling
D. Use the sling without further evaluation
Answer: C. Determine the actual load distribution before selecting the sling
Rationale: Multiple-leg slings do not necessarily share load equally. Sling angle,
load geometry, stiffness, and attachment points can cause unequal loading.
3. What happens to the tension in each leg of a two-leg sling as the sling angle
becomes smaller relative to the horizontal?
A. It decreases
B. It remains constant
C. It increases
D. It becomes zero
Answer: C. It increases
Rationale: As the sling approaches a horizontal orientation, leg tension rises
substantially. Low sling angles can therefore create forces much greater than
the weight of the load.
4. A 10,000-lb load is lifted with two sling legs, each making a 30° angle above
the horizontal. Approximately what tension exists in each leg if the load is
equally shared?
A. 2,500 lb
B. 5,000 lb
C. 10,000 lb
D. 20,000 lb
Answer: C. 10,000 lb
Rationale: For equal loading, leg tension = W ÷ (2 × sin 30°) = 10,000 ÷ 1 = 10,000
lb per leg.
, 5. Which condition is most likely to damage a synthetic web sling?
A. Properly padded corners
B. Smooth rounded lifting points
C. Sharp edges without protection
D. Correctly rated shackles
Answer: C. Sharp edges without protection
Rationale: Sharp edges can cut or severely abrade synthetic fibers. Edge
protection should be used whenever the sling can contact damaging surfaces.
6. What is the main purpose of a shackle's screw pin or bolt?
A. To increase the crane's capacity
B. To secure the shackle body and retain the load connection
C. To reduce the load weight
D. To eliminate sling-angle forces
Answer: B. To secure the shackle body and retain the load connection
Rationale: The pin forms the load-bearing connection through the shackle body.
It must be properly installed and compatible with the shackle's design and
rating.
7. Why should a rigger never stand directly beneath a suspended load?
A. It interferes with the operator's visibility
B. The crane becomes unstable
C. A failure could cause the load or rigging to fall onto the person
D. It increases sling capacity
Answer: C. A failure could cause the load or rigging to fall onto the person
Rationale: Suspended loads represent a severe struck-by and crushing hazard.
Personnel should remain outside the fall zone whenever practicable.
8. What should be done if a wire-rope sling has a damaged eye or severe
localized crushing?
A. Rotate the damage away from the load
, B. Lubricate it and continue using it
C. Remove it from service for evaluation
D. Double its rated capacity
Answer: C. Remove it from service for evaluation
Rationale: Structural damage to an eye or severe crushing can reduce sling
strength. A questionable sling must not be used until properly evaluated under
applicable requirements.
9. What is the center of gravity of a uniformly shaped, uniformly dense
rectangular object?
A. At the highest point
B. At its geometric center
C. At the lowest corner
D. Always directly above the first sling connection
Answer: B. At its geometric center
Rationale: For a uniformly shaped and uniformly dense rectangular object, the
center of gravity is located at the geometric center.
10.Why is locating the center of gravity essential before lifting an irregular
load?
A. It determines the crane's fuel consumption
B. It helps establish proper lifting-point placement and load balance
C. It eliminates the need for tag lines
D. It determines the weather conditions
Answer: B. It helps establish proper lifting-point placement and load balance
Rationale: If the hook is not positioned appropriately relative to the center of
gravity, the load can tilt, rotate, or shift unexpectedly during the lift.
11.What is the safest action if a load begins to tilt unexpectedly during the
initial test lift?
A. Raise it higher to stabilize it
Advanced 100-Question Practice Exam
2026 | Questions & Answers with
Detailed Rationales | Complete Exam
Prep & Study Guide
1. What is the primary purpose of determining the working load limit (WLL) of
a sling before making a lift?
A. To determine the crane's maximum radius
B. To ensure the sling is not loaded beyond its rated capacity
C. To determine the load's center of gravity
D. To determine the operator's required certification
Answer: B. To ensure the sling is not loaded beyond its rated capacity
Rationale: The WLL establishes the maximum permitted load for the sling under
specified conditions. Exceeding it can cause sling failure, dropped loads, and
serious injuries.
2. A rigger is preparing a four-leg bridle sling, but the load is supported
primarily by only two legs because of uneven geometry. What is the safest
approach?
, A. Assume all four legs share the load equally
B. Increase the crane capacity
C. Determine the actual load distribution before selecting the sling
D. Use the sling without further evaluation
Answer: C. Determine the actual load distribution before selecting the sling
Rationale: Multiple-leg slings do not necessarily share load equally. Sling angle,
load geometry, stiffness, and attachment points can cause unequal loading.
3. What happens to the tension in each leg of a two-leg sling as the sling angle
becomes smaller relative to the horizontal?
A. It decreases
B. It remains constant
C. It increases
D. It becomes zero
Answer: C. It increases
Rationale: As the sling approaches a horizontal orientation, leg tension rises
substantially. Low sling angles can therefore create forces much greater than
the weight of the load.
4. A 10,000-lb load is lifted with two sling legs, each making a 30° angle above
the horizontal. Approximately what tension exists in each leg if the load is
equally shared?
A. 2,500 lb
B. 5,000 lb
C. 10,000 lb
D. 20,000 lb
Answer: C. 10,000 lb
Rationale: For equal loading, leg tension = W ÷ (2 × sin 30°) = 10,000 ÷ 1 = 10,000
lb per leg.
, 5. Which condition is most likely to damage a synthetic web sling?
A. Properly padded corners
B. Smooth rounded lifting points
C. Sharp edges without protection
D. Correctly rated shackles
Answer: C. Sharp edges without protection
Rationale: Sharp edges can cut or severely abrade synthetic fibers. Edge
protection should be used whenever the sling can contact damaging surfaces.
6. What is the main purpose of a shackle's screw pin or bolt?
A. To increase the crane's capacity
B. To secure the shackle body and retain the load connection
C. To reduce the load weight
D. To eliminate sling-angle forces
Answer: B. To secure the shackle body and retain the load connection
Rationale: The pin forms the load-bearing connection through the shackle body.
It must be properly installed and compatible with the shackle's design and
rating.
7. Why should a rigger never stand directly beneath a suspended load?
A. It interferes with the operator's visibility
B. The crane becomes unstable
C. A failure could cause the load or rigging to fall onto the person
D. It increases sling capacity
Answer: C. A failure could cause the load or rigging to fall onto the person
Rationale: Suspended loads represent a severe struck-by and crushing hazard.
Personnel should remain outside the fall zone whenever practicable.
8. What should be done if a wire-rope sling has a damaged eye or severe
localized crushing?
A. Rotate the damage away from the load
, B. Lubricate it and continue using it
C. Remove it from service for evaluation
D. Double its rated capacity
Answer: C. Remove it from service for evaluation
Rationale: Structural damage to an eye or severe crushing can reduce sling
strength. A questionable sling must not be used until properly evaluated under
applicable requirements.
9. What is the center of gravity of a uniformly shaped, uniformly dense
rectangular object?
A. At the highest point
B. At its geometric center
C. At the lowest corner
D. Always directly above the first sling connection
Answer: B. At its geometric center
Rationale: For a uniformly shaped and uniformly dense rectangular object, the
center of gravity is located at the geometric center.
10.Why is locating the center of gravity essential before lifting an irregular
load?
A. It determines the crane's fuel consumption
B. It helps establish proper lifting-point placement and load balance
C. It eliminates the need for tag lines
D. It determines the weather conditions
Answer: B. It helps establish proper lifting-point placement and load balance
Rationale: If the hook is not positioned appropriately relative to the center of
gravity, the load can tilt, rotate, or shift unexpectedly during the lift.
11.What is the safest action if a load begins to tilt unexpectedly during the
initial test lift?
A. Raise it higher to stabilize it
