22 Site Assessment & Setup Practice Questions & Answers

1. 1. Two days of heavy rain have left the planned crane set-up area soft, rutted, and holding standing water. Before the crane may be assembled or used at that location, what condition must exist?

   • A.Soft ground is acceptable as long as the outriggers are fully extended and the floats are attached
   • B.The operator may work off the wet ground provided every lift is held under half of the charted capacity
   • C.The ground must be firm, drained and graded to a degree that, together with supporting materials such as mats or cribbing, the manufacturer's requirements for support and levelness are met✓ Answer
   • D.Standing water matters only for crawler cranes, since wheeled cranes bear on outrigger floats

   The federal crane standard defines ground conditions as the ability of the ground to support the equipment, including slope, compaction and firmness, and prohibits assembly or use unless the ground is firm, drained and graded so that, in conjunction with supporting materials, the manufacturer's specifications for adequate support and degree of level are met. Mats and cribbing spread load; they cannot substitute for bearing capacity the soil does not have, and derating the lift does not cure a soil failure.

   Source: OSHA 29 CFR 1926.1402 — ground conditionsReport a problem with this question

2. 2. Project drawings held by the general contractor show an abandoned underground fuel tank beneath the area where the crane is to be set up. Who is responsible for informing the crane user and the operator of that hazard?

   • A.The operator, who must research the site's history before arriving
   • B.The crane rental company that delivered the machine
   • C.The utility owner whose lines cross the property
   • D.The controlling entity — the entity with overall responsibility for the project site✓ Answer

   The federal crane standard places two duties on the controlling entity: ensure that ground preparations adequate to meet the ground-condition requirement are provided, and inform the user and the operator of hazards beneath the set-up area — voids, tanks, utilities — that are identified in documents in its possession or otherwise known to it. Where there is no controlling entity, that duty falls on the employer of the operator or the assembly/disassembly director.

   Source: OSHA 29 CFR 1926.1402 — ground conditions and controlling entity dutiesReport a problem with this question

3. 3. During set-up the assembly/disassembly director concludes that the ground will not adequately support the crane in the planned configuration. What does the standard require next?

   • A.Continue with a shorter load radius and watch the floats for settling
   • B.Add one course of cribbing under each float and continue, since cribbing spreads the load
   • C.Hand the decision to the operator, who has the final say on the set-up
   • D.Stop, and have his employer discuss the needed ground preparations with the controlling entity before work proceeds✓ Answer

   When the assembly/disassembly director or the operator determines that ground conditions do not meet the requirement, that person's employer must discuss the needed ground preparations with the controlling entity; the correct path is to stop and escalate, not to improvise a work-around. Cribbing may well be part of the eventual fix, but it is only adequate when a qualified determination says the prepared ground plus the supporting materials will carry the imposed loads.

   Source: OSHA 29 CFR 1926.1402 — ground conditionsReport a problem with this question

4. 4. The only position that gives the crane the radius it needs sits directly over a utility trench that was backfilled last week and has not been compacted or tested. What is the correct response?

   • A.Do not set up over the uncompacted backfill until a qualified person evaluates the support, or reposition the crane onto undisturbed ground✓ Answer
   • B.Set up as planned but keep the boom out of the quadrant over the trench
   • C.Bridge the trench with steel mats, since mats always make disturbed ground acceptable
   • D.Set up and watch the floats; if nothing settles in the first few minutes the ground is proven

   Loose or uncompacted backfill is a classic below-surface hazard: the soil beneath the float can consolidate or shear under load with little warning, and a sudden corner settlement is a tipping event. Mats and cribbing only spread the imposed load over a larger area; they cannot create bearing capacity that the fill does not have, and swinging away from the trench does not remove the risk because the corner loads shift as the superstructure rotates.

   Source: OSHA 29 CFR 1926.1402 — ground conditions and supporting materialsReport a problem with this question

5. 5. One outrigger float carries an imposed load of 24,000 lb. The float is set on a timber mat that spreads that load over 16 square feet of ground contact. What ground bearing pressure does that corner impose?

   • A.384,000 psf
   • B.1,500 psf✓ Answer
   • C.6,000 psf
   • D.150 psf

   Ground bearing pressure equals the imposed load divided by the contact area: 24,000 lb ÷ 16 sq ft = 1,500 psf. That is the whole reason mats and cribbing are used — enlarging the bearing area lowers the pressure in direct proportion. Whether 1,500 psf is acceptable is a separate question answered by the ground's allowable bearing capacity as determined by a qualified person, not by the crane operator's judgment.

   Source: Ground bearing pressure = imposed load ÷ contact area; OSHA 29 CFR 1926.1402 supporting materialsReport a problem with this question

6. 6. A crew is placing blocking under the outriggers of a telescopic boom crane. Which placement is correct?

   • A.Under the outrigger beam close to the machine, so the beam is supported along its length
   • B.Under the outer end of the outrigger beam, with the float hanging free
   • C.Under the tires, so the tires share the load with the floats
   • D.Centered under the float so the entire float bears on the blocking, on a level, prepared surface✓ Answer

   Blocking and cribbing belong under the float or pad, centered so the full float area bears evenly, on a level prepared surface. Blocking placed under the outrigger beam or box loads the beam in a way it was never designed for and can bend or fail the structure; leaving part of the float unsupported concentrates pressure on an edge. The blocking itself must also be of adequate size, thickness, strength and condition — free of rot, splits and other defects.

   Source: OSHA 29 CFR 1926.1404 — blocking size, condition and placement during assembly/disassemblyReport a problem with this question

7. 7. A crew wants to lay loose steel outrigger floats on the ground and then lower the outrigger jacks onto them. What does the federal crane standard require?

   • A.When floats are used they must be attached to the outriggers or stabilizers✓ Answer
   • B.Floats may be left loose as long as cribbing is placed under them
   • C.Loose floats are acceptable if they are centered by eye before the jack touches down
   • D.Floats are needed only when the crane is set up on unpaved ground

   The standard requires that outrigger or stabilizer floats, when used, be attached to the outrigger or stabilizer. An unattached float can shift, tip or kick out as the jack loads it or as the corner load changes with boom position, and the loss of bearing area under one corner is exactly the condition that starts a tipping sequence. Cribbing under a loose float does not satisfy the attachment requirement.

   Source: OSHA 29 CFR 1926.1404 — outrigger and stabilizer floatsReport a problem with this question

8. 8. The crane must be set up in a narrow alley where one outrigger cannot be fully extended. What would make that set-up acceptable?

   • A.Any intermediate position is fine if the operator derates the chart by the percentage the beam is retracted
   • B.It is acceptable as long as no load exceeds half of the fully extended capacity
   • C.Only if the manufacturer's procedures permit that intermediate position and the load chart published for that position is the chart actually used✓ Answer
   • D.Operating anywhere other than fully extended or fully retracted is never permitted

   The standard allows outriggers and stabilizers to be either fully extended or, if the manufacturer's procedures permit, deployed at a specified intermediate position — and the capacities used must come from the load chart published for that exact position. Inventing a percentage reduction is not permitted, because capacity does not fall off in proportion to beam extension: it depends on the tipping geometry the manufacturer tested for each configuration.

   Source: OSHA 29 CFR 1926.1404 — outrigger and stabilizer extension; manufacturer's load chart for the configuration in useReport a problem with this question

9. 9. After setting the outriggers, the operator sees that the tires are still lightly in contact with the ground. What is required?

   • A.That is preferred, because the tires add stability
   • B.The outriggers must be set so that the weight of the equipment is removed from the wheels✓ Answer
   • C.It is acceptable as long as the crane reads level
   • D.It is acceptable if the tire pressures are at the manufacturer's specification

   When outriggers or stabilizers are used, they must be set so the equipment's weight comes off the wheels, with the sole exception of locomotive cranes. The on-outrigger load chart assumes the machine is supported at the outrigger points only; tires still bearing change the support geometry, and as the tires compress or the ground yields the machine can shift and go out of level during a lift.

   Source: OSHA 29 CFR 1926.1404 — outriggers and stabilizersReport a problem with this question

10. 10. While the outriggers are being extended and set, what does the federal crane standard require regarding observation?

    • A.An oiler must stand at the outrigger box and operate the control from there
    • B.Only the outriggers on the load side of the machine need to be observed
    • C.The area must simply be barricaded so that no one has to watch the beams
    • D.Each outrigger or stabilizer must be visible to the operator or to a signal person during extension and setting✓ Answer

    The standard requires that each outrigger or stabilizer be visible to the operator or to a signal person during extension and setting. That watch does two things: it keeps people out of the pinch and crush points created by the moving beam and float, and it confirms that the beam actually reached the extension that matches the load chart being used.

    Source: OSHA 29 CFR 1926.1404 — outriggers and stabilizersReport a problem with this question

11. 11. The outrigger position sensors are reporting to the rated capacity limiter that all beams are fully extended, but one beam is actually stopped at an intermediate position. What is the consequence, and what should be done?

    • A.The limiter always defaults to the most restrictive chart, so work may continue
    • B.Nothing — the sensors only record data and do not affect the capacities used
    • C.The limiter will apply the fully extended chart and overstate capacity, so the beam must be moved to a position that matches the chart actually in use✓ Answer
    • D.The operator should simply reduce swing speed to compensate

    Outrigger position indicators and sensors exist to tell the rated capacity limiter which chart applies. If the reported position is more favorable than the actual one, the limiter permits loads the machine's real tipping geometry cannot support, and the mismatch is a classic overload and tipping scenario. The fix is to make the machine and the chart agree — either fully extend the beam or select and work to the chart for the actual position, if the manufacturer publishes one.

    Source: OSHA 29 CFR 1926.1404 outrigger requirements; ASME B30.5 — rated capacity limiter configurationReport a problem with this question

12. 12. A crane is set up on outriggers about two degrees out of level. Why does that matter?

    • A.It increases capacity over the front and reduces it over the rear, so it can be managed by choosing a quadrant
    • B.It only affects the accuracy of the boom angle indicator
    • C.It has no effect on capacity as long as the outriggers are fully extended
    • D.The suspended load hangs out away from the machine, increasing the actual radius and side-loading the boom, so capacity falls sharply; the crane must be leveled to the manufacturer's specification✓ Answer

    Load charts are built on a level machine. When the crane is out of level the boom tip moves downhill, the load hangs plumb from wherever the tip actually is, and the operating radius grows beyond what the operator selected — capacity is lost far out of proportion to the small angle, and the boom picks up side loading it was not designed to carry. Level must be verified against the manufacturer's specification, commonly within one percent of grade, and rechecked after the machine settles.

    Source: ASME B30.5 — mobile crane leveling and stability; manufacturer's operating manualReport a problem with this question

13. 13. For configurations whose ratings are limited by stability rather than structure, rated loads under the mobile crane standard are what portion of the load that would tip the crane?

    • A.75% on outriggers and 85% on rubber or crawlers
    • B.85% on outriggers and 75% on rubber or crawlers✓ Answer
    • C.100% on outriggers and 85% on rubber or crawlers
    • D.50% of the tipping load in every configuration

    The mobile crane standard sets stability-limited ratings at 85 percent of the tipping load when the crane is on outriggers and 75 percent when it is on rubber or on crawlers, the lower figure reflecting the softer, less predictable support that tires and tracks provide. The margin is small, which is why level, full support and correct radius matter so much. Ratings limited by structural strength are not derived from tipping and are not reduced by those percentages.

    Source: ASME B30.5 — stability basis for rated loadsReport a problem with this question

14. 14. A crane is set up with all outriggers equally extended and the load will be swung from over the rear around to over the side. How does boom position affect the loading on the supporting ground?

    • A.Each outrigger always carries roughly one quarter of the combined weight of the crane and load
    • B.Ground loading stays even, because the outriggers are extended the same amount
    • C.The corner nearest the boom takes a disproportionate share, and the maximum corner load can far exceed the total weight divided by four✓ Answer
    • D.Only tires or crawler tracks, not outriggers, are affected by swinging

    Boom position — elevation and quadrant — is one of the elements that determines ground stability, because swinging moves the combined center of gravity toward one corner of the outrigger pattern. The corner under and near the boom can carry a large multiple of the average share, so mats and cribbing must be sized for the maximum corner load in the worst boom position, not for the total weight divided by four. Crawler track loading shifts the same way and is never uniform along the track.

    Source: OSHA 29 CFR 1926.1402 ground conditions (boom position as a stability element); ASME B30.5Report a problem with this question

15. 15. A crew must assemble a lattice boom within reach of an overhead transmission line. Which of the following satisfies the standard before assembly begins?

    • A.Relying on an insulating link in the boom and on non-metallic slings
    • B.Assuming the line is dead because no service appears to be connected to it
    • C.Keeping 10 feet of clearance, because that is the minimum for lines of any voltage
    • D.Confirming with the utility owner or operator that the line has been deenergized and that it is visibly grounded at the worksite✓ Answer

    Before assembly or disassembly near power lines the employer must identify the work zone and use one of three options: confirm from the utility owner or operator that the line is deenergized and visibly grounded at the worksite; keep the blanket minimum clearance of 20 feet; or determine the voltage and use the clearance from the standard's table, in which case at least one encroachment-prevention measure such as a dedicated spotter, proximity alarm or range limiter is also required. Insulating links and visual guesses about whether a line is live are never a substitute, and any tag lines used must be nonconductive.

    Source: OSHA 29 CFR 1926.1407 — power line safety during assembly and disassemblyReport a problem with this question

16. 16. A crane will operate near an energized 13.8 kV distribution line. The employer has not deenergized the line and, after confirming the voltage with the utility, elects to work to the clearance table in the standard. What minimum clearance applies during operation?

    • A.6 feet
    • B.20 feet
    • C.4 feet
    • D.10 feet✓ Answer

    The federal crane standard's operating clearance table sets 10 feet as the minimum for lines up to 50 kV, with larger distances as voltage rises. The 20-foot figure is the blanket option used when the employer does not determine the voltage — choosing the table option is what allows the smaller distance, and it obliges the employer to have obtained the voltage from the utility and to implement encroachment-prevention measures such as a dedicated spotter, warning barricades and nonconductive tag lines.

    Source: OSHA 29 CFR 1926.1408 Table A — minimum clearance distances during operationReport a problem with this question

17. 17. That same energized 13.8 kV line crosses the haul road. The crane will travel under it with no load and the boom lowered. What minimum clearance applies while traveling?

    • A.20 feet
    • B.6 feet✓ Answer
    • C.4 feet
    • D.10 feet

    Travel with no load and the boom or mast lowered is governed by a separate clearance table in the federal crane standard, which requires 6 feet for lines over 0.75 kV up to 50 kV. Candidates commonly carry over the 10-foot operating figure or the 20-foot blanket assembly figure; the three regimes — operating, assembling or disassembling, and traveling with no load — have different distances and must not be interchanged. Speed, terrain, line sag and bouncing must also be accounted for.

    Source: OSHA 29 CFR 1926.1411 Table T — minimum clearance while traveling with no loadReport a problem with this question

18. 18. While the crane travels with no load, some part of the equipment will pass within 20 feet of an energized line. What does the standard require?

    • A.A dedicated spotter in continuous contact with the driver or operator must be used, positioned to see the clearance distance clearly✓ Answer
    • B.Travel speed must be held to a walking pace
    • C.The line must be deenergized before the crane may pass
    • D.Nothing additional, as long as the boom is lowered

    The travel provisions of the federal crane standard require a dedicated spotter in continuous contact with the driver or operator whenever any part of the equipment will get within 20 feet of a power line while traveling. The spotter must be positioned to gauge the clearance accurately; if travel occurs at night or in poor visibility the lines must be illuminated or their location otherwise made known and a safe route established.

    Source: OSHA 29 CFR 1926.1411 — power line safety while traveling with no loadReport a problem with this question

19. 19. The boom contacts an energized power line during a lift. What should the operator do?

    • A.Climb down at once and get away from the machine
    • B.Have a ground worker push the boom clear with a wooden pole
    • C.Stay in the cab, try to move the crane clear of the line if that can be done safely, and warn everyone to stay away from the machine, the load and the rigging✓ Answer
    • D.Have a crew member touch the frame with dry gloves to check whether it is still energized

    While contact persists the machine and everything touching it may be at line potential, and the ground around it carries a step-potential gradient. The operator is safest remaining in the cab, insulated from earth, and should attempt to break contact by moving the crane away from the line only if that can be done safely; everyone else must be kept clear and must not touch the crane, load or rigging. If fire or another hazard forces the operator out, the exit is to jump clear without touching the machine and the ground at the same time and then shuffle or hop away with feet together.

    Source: ASME B30.5 and the AEM Mobile Crane Safety Manual — power line contact proceduresReport a problem with this question

20. 20. Who may serve as the assembly/disassembly director for a mobile crane?

    • A.The site superintendent, since assembly is primarily a scheduling matter
    • B.A competent person only; specific qualification in the equipment is not needed
    • C.A person who is both a competent person and a qualified person, or a competent person assisted by one or more qualified persons✓ Answer
    • D.Any operator holding a current certification for that crane type

    The federal crane standard requires the assembly/disassembly director to be both a competent person and a qualified person, or a competent person assisted by one or more qualified persons. A competent person can identify existing and predictable hazards and is authorized to take prompt corrective action; a qualified person has, through training, experience or professional standing, demonstrated the ability to solve problems relating to the work. The director must understand and review the applicable procedures before work begins and ensure each crew member knows their tasks, the hazards, and the positions to avoid.

    Source: OSHA 29 CFR 1926.1404 — assembly/disassembly directorReport a problem with this question

21. 21. Boom sections are being unpinned during disassembly. Which practice does the federal crane standard require?

    • A.Employees should stand beneath the section to steady it while the pins are driven out
    • B.The boom hoist brake may be relied on without testing, since it is checked at the periodic inspection
    • C.The sections must be supported by blocking, an assist crane or rigging so they remain stable when the pins are removed, and employees must not be under the components during pin removal✓ Answer
    • D.Pins may be removed from an unsupported section as long as the boom is at a low angle

    Among the hazards the assembly/disassembly director must address are maintaining stability upon pin removal by using blocking, rigging or supports, placing blocking so it protects the structural integrity of the component, verifying assist crane loads, identifying the center of gravity, and testing the boom hoist brake before relying on it. Employees must not be under the boom, jib or other components during pin removal except where site constraints require it and the director implements procedures that minimize the exposure time and the risk.

    Source: OSHA 29 CFR 1926.1404 — assembly/disassembly hazard requirementsReport a problem with this question

22. 22. A worker needs to step behind the counterweight, out of the operator's view, to reach a hose fitting. What must happen before the superstructure rotates?

    • A.Rotation is allowed at reduced speed while the worker is out of view
    • B.He may proceed as long as the swing alarm is working
    • C.The operator must be informed before the worker goes there, and must not rotate the superstructure until told the worker is in a safe position✓ Answer
    • D.He should stay within arm's reach of the counterweight so he can feel it begin to move

    Before an employee goes to a location out of the operator's view where the rotating superstructure creates a struck-by, pinch or crush hazard, the operator must be informed, and rotation must not begin until the operator is told the employee is in a safe position — a prearranged communication system, not an alarm, is what protects the worker. The employer must also erect and maintain control lines, warning lines or barriers marking the accessible swing area, or, where that is demonstrably infeasible, post conspicuous swing-zone warning signs with high-visibility markings and train employees to recognize the hazard.

    Source: OSHA 29 CFR 1926.1424 — work area control around the rotating superstructureReport a problem with this question

Practice questions based on the published NCCCO mobile crane operator exam outlines and the consensus safety practices the trade runs on. 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. Capacity always comes from the load chart for the machine and configuration in front of you, and wind, ground-bearing and permit limits are set by the manufacturer's manual and the authority having jurisdiction — never from a practice question. Confirm current exam requirements before testing. About CCO certification →