21 Load Control & Completing the Lift Practice Questions & Answers
Every Load Control & Completing the Lift practice question from the Rigger Level I (NCCCO) Practice Test, with the correct answer and a short explanation.
Start practice test →1. In rigging, what does the center of gravity of a load refer to?
- A.The place where the heaviest material in the load physically sits
- B.The point on the load's top surface midway between its two ends
- C.The geometric middle found by measuring the load's length and width
- D.The single point where the whole weight of the load is taken to act✓ Answer
The center of gravity is the balance point of the load: the one point where its entire weight can be treated as acting, in any position the load is turned to. It is rarely the geometric middle, because material is almost never distributed evenly, which is why the hook must be set over the center of gravity and not over the middle of the object.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load characteristics)Report a problem with this question
2. A skid-mounted pump unit has a heavy motor bolted at one end and an empty frame at the other, and no drawing is available. How should the rigger judge where the center of gravity lies?
- A.Assume it lies toward the empty frame end, because that end has less support
- B.Assume it lies toward the motor end, and set the hook over that estimated point✓ Answer
- C.Assume it lies under the lifting lugs, wherever the fabricator welded those lugs
- D.Assume it lies at the midpoint of the skid, since the skid carries the whole unit
The center of gravity always shifts toward the concentrated mass, so on this unit it sits toward the motor. Lifting lugs are welded where the structure is strong, not necessarily over the balance point, and the estimate is then confirmed by lifting the unit a few inches and seeing whether it hangs level.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load characteristics)Report a problem with this question
3. When the hook is not directly over the center of gravity, what happens as the slings take up the weight?
- A.The load rises evenly, and the leg nearest the hook carries no tension
- B.The load stays level, and the extra weight is shared out by the other legs
- C.The load lifts with one end high, and it stays locked in that attitude
- D.The load swings sideways until its center of gravity settles under the hook✓ Answer
A freely suspended load always hangs with its center of gravity directly below the hook. If the hook starts off to one side, the load shifts or swings sideways the instant it is free of the ground, which can strike workers, shift the slings in the hook and drop the load.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load characteristics)Report a problem with this question
4. How does the height of the sling attachment points relative to the load's center of gravity affect stability?
- A.Attachment points above the center of gravity give the most stable lift✓ Answer
- B.Attachment points below the center of gravity give the most stable lift
- C.Attachment points level with the center of gravity give the most stable lift
- D.Attachment point height does not matter once the hook is over the load
With the attachment points above the center of gravity the load hangs like a pendulum and returns to level after a disturbance. Points level with the center of gravity leave it neutral, and points below it make the load want to roll over, so it can capsize as soon as it is clear of the ground.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load stability)Report a problem with this question
5. An 8,000 lb load hangs on a two-leg bridle with each leg at 60 degrees from horizontal. Using a load angle factor of 1.155 for 60 degrees, what is the tension in each leg?
- A.4,000 lb
- B.8,000 lb
- C.9,240 lb
- D.4,620 lb✓ Answer
Each leg carries the weight divided by the number of legs, multiplied by the load angle factor: (8,000 / 2) x 1.155 = 4,620 lb. Stopping at 4,000 lb is the classic error of dividing by the legs and ignoring the angle; the factor is never less than 1.0, so leg tension always exceeds the simple share.
Source: ASME B30.9 Slings (load angle factor)Report a problem with this question
6. A 10,000 lb load is lifted on a two-leg bridle with each leg at 45 degrees from horizontal. Using a load angle factor of 1.414 for 45 degrees, what is the tension in each leg?
- A.5,000 lb
- B.7,070 lb✓ Answer
- C.14,140 lb
- D.3,535 lb
Leg tension is the share of the weight times the load angle factor: (10,000 / 2) x 1.414 = 7,070 lb. At 45 degrees each leg carries about 41 percent more than its simple half share, which is why the sling must be rated against the calculated leg tension and not against the weight divided by two.
Source: ASME B30.9 Slings (load angle factor)Report a problem with this question
7. A lift plan shows a two-leg bridle working at a horizontal sling angle of 25 degrees. What is the correct response to that angle?
- A.Treat it as acceptable, since any angle greater than 15 degrees is allowed
- B.Treat it as unacceptable unless the sling maker or a qualified person approves it✓ Answer
- C.Treat it as acceptable, provided each leg is derated by one quarter of its rating
- D.Treat it as unacceptable unless the load weighs under half the sling's rating
Horizontal sling angles below 30 degrees are not used unless the sling manufacturer or a qualified person approves them, because leg tension climbs very steeply as the angle flattens. At 30 degrees each leg already carries twice its share of the weight, and the rise below that is far faster than most riggers expect.
Source: ASME B30.9 SlingsReport a problem with this question
8. A machine base is picked from a lug at each end, but its center of gravity is well off center. Using an adjustable chain bridle, how is the base brought up level?
- A.Lengthen both legs equally so the bridle angle can flatten out under load
- B.Shorten the leg at the heavy end so the hook sits over the center✓ Answer
- C.Leave the legs equal and let the load drift until it finds its own level
- D.Shorten the leg at the light end so that both legs pull the same amount
Shortening the leg on the heavy end moves the hook toward that end, which is exactly what places the hook over the center of gravity and lets the base hang level. The two legs still carry unequal shares of the weight, so each leg must be rated for the heavier share, not for half the load.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load stability)Report a problem with this question
9. A long fabricated panel keeps turning slowly on the hook as it is hoisted. What is the correct way to control that rotation?
- A.Attach two tag lines at opposite ends and control the panel from the ground✓ Answer
- B.Attach one tag line at midlength and hold it from directly under the panel
- C.Have a worker reach up and steady the panel by hand until the turning stops
- D.Put a half twist in one sling leg so the wrap resists any further turning
Two tag lines at opposite ends act as a couple, so a light pull on either one resists rotation while both riggers stand well outside the fall zone. A single line under the load puts a worker beneath it, steadying by hand puts hands into pinch points, and a twist in a sling leg is a defect rather than a control.
Source: OSHA 29 CFR 1926.1425Report a problem with this question
10. Under what condition should a tag line be rigged on a load before it leaves the ground?
- A.When the load must travel higher than the head height of the workers nearby
- B.When the load weighs more than half the rated capacity of the slings in use
- C.When the load could swing or turn and workers must guide it from a distance✓ Answer
- D.When the load is rigged on a single sling leg instead of a two-leg bridle
A tag line exists so the load can be steadied and guided without anyone touching it or standing under it, so one is needed whenever wind, shape or the travel path could let the load swing or spin. Sling capacity, travel height and the number of legs do not decide the question; exposure to an uncontrolled load does.
Source: OSHA 29 CFR 1926.1425Report a problem with this question
11. How should a tag line be rigged, and where does the rigger work while using it?
- A.Tied low on the load and long enough for the rigger to stay clear of it✓ Answer
- B.Tied to a sling leg and wrapped once around the rigger's hand for grip
- C.Tied at a top corner and short enough to keep the rigger right alongside
- D.Tied to the hook block and short enough that the rigger walks under it
The line is secured to the load itself, low enough that it does not lift with the rigging, and long enough that the rigger can stand outside the fall zone and clear of the travel path. It is held in the hands and never wrapped around a hand, arm or belt, so the rigger can let go instantly if the load moves.
Source: OSHA 29 CFR 1926.1425Report a problem with this question
12. A synthetic web sling is a little too long for the pick. Under OSHA 29 CFR 1910.184, how may the rigger shorten it?
- A.By choosing a shorter sling, because knots, bolts and makeshift devices are barred✓ Answer
- B.By twisting the sling body several turns, with the load kept under half the rating
- C.By bolting a loop into the sling body, with the bolt left only hand tight
- D.By tying one overhand knot in the sling body, kept well away from sharp edges
Slings may not be shortened with knots, bolts or other makeshift devices, so the answer is always to select a sling of the right length. A knot forces a sharp bend and concentrates stress at one spot, cutting the sling's strength roughly in half, and the sling then fails at the knot with no warning.
Source: OSHA 29 CFR 1910.184(c)(5)Report a problem with this question
13. Which knot joins two ropes of different diameter, and how is it formed?
- A.The bowline, with the larger rope forming a loop the smaller rope is tied into
- B.The square knot, with both ropes crossed so the free ends finish on one side
- C.The sheet bend, with the larger rope forming the bight the smaller passes through✓ Answer
- D.The clove hitch, with the larger rope wrapped twice around the smaller rope end
The sheet bend is the knot for joining ropes of unequal diameter: the larger, stiffer rope is bent into a bight and the smaller rope is passed up through it and tucked under itself, so the pull jams the bend tighter. A square knot is only for two ropes of the same size and will capsize and slip when the sizes differ.
Source: CCO Rigger Reference Manual (knots)Report a problem with this question
14. What is a shock load, and why is it dangerous to rigging?
- A.A cutting force from a sharp corner that wears the sling where it wraps a load
- B.A twisting force from an off-center pick that loads one leg more than the rest
- C.A steady force from a long hoist that slowly fatigues the sling above its rating
- D.A sudden force from fast starting or stopping that far exceeds the load's weight✓ Answer
Shock loading comes from rapid acceleration or deceleration: snatching up slack, jerking a stuck load free, a hard stop, or a load that drops and is caught by the slings. The momentary force can be several times the static weight and can exceed the breaking strength without warning, which is why it is prohibited outright.
Source: OSHA 29 CFR 1910.184(c)(11)Report a problem with this question
15. How should the hoist be run when first taking the weight of a load, so that shock loading is avoided?
- A.Take up the slack slowly and bring the load off the ground with a smooth start✓ Answer
- B.Take up the slack quickly so the slings snap tight and seat in the hook bowl
- C.Take up the slack slowly, then lift fast to clear the ground in one motion
- D.Take up the slack quickly, then stop hard once to prove the slings will hold
The force in the rigging equals the weight plus whatever is needed to accelerate it, so a slow take-up of slack and a smooth start keep that extra force small. Snapping the slack tight, lifting abruptly or braking hard all add acceleration forces that the slings were never rated for.
Source: OSHA 29 CFR 1910.184(c)(11)Report a problem with this question
16. The load has been raised a few inches clear of the ground and stopped. What is checked at that moment?
- A.That the load hangs level, the slings are seated and nothing is slipping✓ Answer
- B.That the tag lines are tied off and the travel route has been signed for
- C.That the blocking left behind is stacked clear of the planned travel path
- D.That the sling tags are all readable and their rated capacities match
Lifting just clear of the ground and stopping is the test of the rigging decisions: a level hang proves the hook is over the center of gravity, and the pause shows whether the slings have seated in the hook, whether any leg is slipping and whether the load is holding. Tags and capacities are verified before the slings ever go on.
Source: CCO Rigger Reference Manual (trial lift)Report a problem with this question
17. At that first few inches off the ground the load tips noticeably toward one end. What is the correct action?
- A.Raise the load higher so the sling legs can even out and settle it level
- B.Hold the load suspended while a worker pushes the low end back up to level
- C.Continue the lift slowly and let the tag line pull the low end up to level
- D.Land it, reposition the rigging for the center of gravity, and lift again✓ Answer
A load that hangs out of level is telling the rigger the hook is not over the center of gravity, and nothing about lifting it higher changes that relationship. The load is set back down and the rigging moved or adjusted, because reaching in to correct a suspended load puts hands and bodies in the fall zone and in pinch points.
Source: CCO Rigger Candidate Handbook, Rigger Level I Written Examination Outline (load stability)Report a problem with this question
18. A load is being set down on a concrete floor. How should the blocking under it be arranged?
- A.Placed only under the two ends so the middle of the load can flex as it lands
- B.Sized to carry the load and placed directly under every sling leg contact
- C.Sized to carry the load and placed so the slings can be pulled out freely✓ Answer
- D.Stacked as high as the slings are wide so the legs hang clear underneath
Blocking has two jobs: it must carry the load without crushing or letting it tip, and it must hold the load high enough and in the right places that the slings come out by hand. Blocking placed under the sling contact points traps the slings, and a sling can never be pulled out from under a resting load.
Source: OSHA 29 CFR 1910.184(c)(13)Report a problem with this question
19. Before the slings are slackened and taken off, what condition must the landed load meet?
- A.It must be set down on bare ground so the full footprint takes the weight
- B.It must be held an inch clear so the slings can be drawn out cleanly
- C.It must rest stable on its supports and be blocked so it cannot tip or roll✓ Answer
- D.It must still rest on one sling leg so the hoist keeps some of the weight
The rigging may be released only once the load is fully supported and cannot move, which means blocked, cribbed, chocked or otherwise secured on a surface that will carry it. A tall or round load can stand quite steady while the slings still hold it and then topple the instant they go slack.
Source: OSHA 29 CFR 1926.251Report a problem with this question
20. A sling is trapped under a load that has been set down. Under OSHA 29 CFR 1910.184, how is it freed?
- A.Pull the sling out with the hoist, using a slow steady pull to avoid jerks
- B.Raise or roll the load off the sling with a jack or bar, then draw it out✓ Answer
- C.Raise the load on the hoist again and hold it while the sling is dragged out
- D.Pull the sling out by hand with two riggers taking an in-line steady pull
A sling is never pulled out from under a load that is resting on it, whether by hand or by machine: dragging abrades and cuts the sling and can pull the load off its supports onto the riggers. The load is jacked, cribbed or rolled off the sling first, and no one reaches under a suspended load to drag rigging clear.
Source: OSHA 29 CFR 1910.184(c)(13)Report a problem with this question
21. The lift is finished and the rigging is off the load. How should the slings and hardware be handled?
- A.Coiled and left at the lift point on the ground for the next crew to use
- B.Stacked on the ground by the load and rinsed off before the next shift
- C.Cleaned and stored on racks in a dry place, with damaged gear tagged out✓ Answer
- D.Left hanging on the hook overnight so the rigging stays with the machine
Slings and hardware are stored clean, dry and off the ground, on racks and away from moisture, chemicals, heat and sharp edges, because ground storage invites cuts, grit, corrosion and crushing by traffic. Anything found damaged during the job is tagged and removed from service at once rather than returned to the rack.
Source: OSHA 29 CFR 1926.251(a)(1)Report a problem with this question
Practice questions built from the published NCCCO Rigger Level I written examination outline and the consensus rigging practices of the ASME B30 series and the OSHA rigging regulations. CCO and NCCCO are marks of the National Commission for the Certification of Crane Operators; this site is not affiliated with or endorsed by NCCCO. This bank covers the WRITTEN examination only — Rigger Level I certification also requires a hands-on practical examination that no multiple-choice question can prepare you for, and there is no substitute for supervised practice with real gear. Capacity always comes from the identification tag and the manufacturer's rating for the specific sling, shackle or device in your hands, never from a practice question. Confirm current requirements with NCCCO before testing. Official exam outline →