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NCCCO Tower Crane study materials
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NCCCO Tower Crane practice questions

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Question 1Site Preparation and Crane Setup

Which information is used to size a tower crane's concrete foundation?

  1. The manufacturer's foundation design loads Correct answer.
  2. The rated capacity at the jib tip
  3. The crane's total operating weight, including all counterweight
  4. The height of the finished building above grade

Explanation

A crane foundation is designed for the reactions the manufacturer publishes for each specific crane configuration: overturning moment, shear, and vertical loads including tension. Overall weight, building height, and tip capacity do not define those reactions.

Question 2Site Preparation and Crane Setup

A crane base is to be placed on a site with variable fill. Which document gives the allowable soil bearing value used to check the foundation?

  1. The geotechnical report prepared for the site Correct answer.
  2. The manufacturer's load chart for the jib length being used
  3. The rigging plan for the heaviest pick
  4. The project fall protection plan

Explanation

Allowable bearing pressure comes from the site's geotechnical investigation, which characterizes the actual soils and fill at the base location. The load chart, rigging plan, and fall protection plan do not describe soil capacity.

Question 3Site Preparation and Crane Setup

Unless the utility or a qualified person specifies otherwise, what is the minimum clearance from a power line rated at 50 kV or less to any part of the crane?

  1. 10 feet Correct answer.
  2. 6 feet
  3. 25 feet
  4. 4 feet

Explanation

The OSHA crane standard's Table A requires 10 feet for lines rated up to 50 kV, with greater distances for higher voltages. De-energizing, grounding, or an insulating barrier is needed before working closer.

Question 4Site Preparation and Crane Setup

Buried tanks and old foundations are suspected beneath a proposed crane location. What must be done before the base is built there?

  1. Assume the soil profile is uniform and proceed
  2. Verify conditions with test pits, borings, or records Correct answer.
  3. Build the base first and check settlement after erection
  4. Rely on the crane's own weight to consolidate the ground

Explanation

Voids, buried debris, and old structures create unpredictable settlement and can collapse under foundation loads, so the actual subsurface conditions must be confirmed before design. Physical investigation or reliable as-built records are the accepted methods.

Question 5Site Preparation and Crane Setup

The crane assembly area must be laid out so that:

  1. counterweights can be stacked against the crane's base section
  2. delivery trucks can park inside the crane's slewing radius during erection
  3. the erection crew can stand beneath the mast sections while they are pinned
  4. the assist crane can set each part without moving under load Correct answer.

Explanation

The assist crane must be able to reach every component from a set position, because swinging a suspended load while traveling is a prohibited and hazardous practice. The layout therefore sizes the pad around the assist crane's reach, not around parking convenience.

Question 6Site Preparation and Crane Setup

Before an assist crane lifts mast sections, the ground under its outriggers must be:

  1. evaluated and prepared for the outrigger loads Correct answer.
  2. frozen solid to increase its stiffness
  3. cleared of all personnel and equipment for a radius of 100 feet
  4. covered with a single layer of plywood

Explanation

Outriggers concentrate very high point loads, so the supporting ground must be assessed and improved with mats, cribbing, or a prepared pad sized for those loads. Plywood alone does not spread load sufficiently and frozen ground may thaw under load.

Question 7Site Preparation and Crane Setup

A crane is to be erected taller than its published free-standing height. What is required?

  1. Ties to the structure at the manufacturer's spacing and loads Correct answer.
  2. Nothing extra, provided the wind is light on the day of erection
  3. Additional counterweight to offset the added height
  4. A shorter jib to reduce the overturning moment

Explanation

Above the free-standing height the mast cannot resist wind and working loads on its own, so the manufacturer's tie (anchorage) scheme must be followed. Tie spacing, tie capacity, and the structure's ability to resist those forces are all part of that scheme.

Question 8Site Preparation and Crane Setup

Who must confirm that a building can resist the forces a tower crane imposes at its tie points?

  1. A qualified person such as the structural engineer Correct answer.
  2. The crane operator, based on experience with the site
  3. The signal person, who sees the tie points daily
  4. The crane erector, since the ties are crane components

Explanation

Tie forces are imposed on the building's frame, so the structure must be analyzed by a qualified person, typically the project structural engineer, to confirm it can carry them. The erector installs the ties but does not normally perform that structural analysis.

Question 9Site Preparation and Crane Setup

Bonding the crane structure to a grounding electrode is done to:

  1. improve radio reception for the operator
  2. prevent the jib from slewing in the wind
  3. reduce the crane's dead weight on the foundation
  4. provide a low-resistance path to earth for fault current Correct answer.

Explanation

Grounding gives lightning strikes and electrical fault current a defined path to earth instead of through the structure, hoist rope, or personnel. It has no effect on weight, slewing behavior, or communications.

Question 10Site Preparation and Crane Setup

When a tower crane is left out of service, the manufacturer's procedure normally requires that the jib:

  1. weathervane freely with the slew brake released Correct answer.
  2. be pinned firmly to the mast to prevent any movement
  3. be turned into the prevailing wind and then locked
  4. be lowered all the way to the ground

Explanation

Releasing the slew brake lets the jib align itself with the wind, which minimizes the sail area presented to the wind and the resulting loads on the mast. Locking the crane in one position can produce loads the mast was not designed to resist.

Question 11Site Preparation and Crane Setup

A crane that penetrates airspace protected around an airport must be:

  1. painted in high-visibility orange as chosen by the owner
  2. marked and lighted as the FAA determination requires Correct answer.
  3. limited to daylight operation only
  4. equipped with a foghorn and strobe for low visibility

Explanation

Obstruction marking and lighting for structures in navigable airspace follow the FAA's determination for that specific site, which sets colors, light types, and light locations. Owner preference or a self-imposed daylight restriction does not satisfy that requirement.

Question 12Site Preparation and Crane Setup

When selecting the crane's location, the counterjib swing must be kept clear of:

  1. obstructions, other structures, and occupied areas Correct answer.
  2. only the footprint of the crane's own base
  3. only the height of the buildings on the site
  4. only the radius swept by the jib tip at full slew

Explanation

The counterjib and counterweights sweep a radius of their own behind the mast, so the entire slewing envelope must be clear of structures, obstructions, and places where people work. Considering only the jib tip leaves the counterjib side uncontrolled.

Question 13Site Preparation and Crane Setup

When two tower cranes are sited so their jibs can pass over one another, the site plan must include:

  1. identical jib lengths on both cranes
  2. a signal person stationed on the roof of each building
  3. a rule that only one crane may operate on any given day
  4. anti-collision procedures and, where needed, limiting devices Correct answer.

Explanation

Overlapping cranes require planned operating procedures and, where the overlap is significant, devices or operating limits that prevent contact between jibs and ropes. Physical separation alone does not control the hazard once the envelopes overlap.

Question 14Site Preparation and Crane Setup

A crane may be erected on a new concrete foundation only after:

  1. seven full days have passed, regardless of measured strength
  2. the formwork has been stripped and the site cleaned
  3. the anchor bolts have been painted and capped
  4. the concrete has reached the strength the manufacturer requires Correct answer.

Explanation

The controlling requirement is strength, not elapsed time, and the required value comes from the manufacturer or the foundation designer. Stripping forms and cosmetic work are not indicators that the foundation can accept crane loads.

Question 15Site Preparation and Crane Setup

The embedded base legs and anchor bolts of a tower crane must be:

  1. set as close as practical, since base plate holes are oversized
  2. cut to length on site to match the base section
  3. installed after the concrete cures and then grouted in place
  4. set and plumbed within the manufacturer's tolerance Correct answer.

Explanation

Base legs and anchor bolts are embedded before the concrete is placed and must match the manufacturer's position, plumb, elevation, and projection tolerances so the base section assembles without induced stress. Field modification of these components is not permitted.

Question 16Site Preparation and Crane Setup

Where a crane base is next to a public sidewalk, what is required?

  1. A flagger on duty during daylight hours only
  2. A warning sign posted on the crane mast
  3. A fence or barrier that keeps the public out Correct answer.
  4. An audible travel alarm on the crane

Explanation

The base area must be physically enclosed so members of the public cannot walk into the swing radius, climb the mast, or be struck by dropped objects. Signs, flaggers, and alarms supplement but do not replace a barrier.

Question 17Site Preparation and Crane Setup

The ground around a crane foundation should be graded and drained to:

  1. increase the allowable bearing pressure under the base
  2. prevent water from ponding and eroding the soil Correct answer.
  3. make the site look tidy for the client
  4. allow the crane to be washed down daily

Explanation

Standing water softens and erodes the soil that provides bearing and lateral support to the foundation. Positive drainage keeps the supporting soils in the condition assumed by the foundation design.

Question 18Site Preparation and Crane Setup

A crane base is planned 15 feet from the top of a 20-foot-deep excavation. What is the main concern?

  1. The crane will be too far from the work area
  2. The operator will not be able to see into the excavation
  3. The crane's jib will be too short to reach the building
  4. The excavation may reduce the foundation's bearing capacity Correct answer.

Explanation

An open excavation removes the soil that provides lateral support and confining pressure near the footing, so bearing capacity and stability can be reduced. A qualified person must evaluate the setback, slope, and shoring before the base is located there.

Question 19Site Preparation and Crane Setup

For a free-standing tower crane, the foundation is usually governed by:

  1. the crane's static dead weight alone
  2. overturning moment combined with minimum vertical load Correct answer.
  3. wind load on the jib while the crane is fully loaded at minimum radius
  4. the maximum capacity at minimum radius

Explanation

The critical case is typically the large overturning moment occurring together with the minimum vertical load, which produces the greatest uplift or tension on one side of the footing. Dead weight alone, capacity, or wind acting with a full load do not create that combination.

Question 20Site Preparation and Crane Setup

If site conditions prevent use of the manufacturer's standard foundation, the alternative must be:

  1. approved by the crane operator on site
  2. copied from the adjacent building's foundation details
  3. designed and certified by a qualified engineer Correct answer.
  4. built larger in every dimension than the standard design

Explanation

A non-standard foundation must be engineered for the actual crane reactions and site conditions and certified by a qualified engineer, with the manufacturer's acceptance where required. Making it larger does not guarantee the correct load path or reinforcement.

Question 21Site Preparation and Crane Setup

Adding counterweight beyond the manufacturer's specified amount is unsafe because:

  1. it makes the crane slower to slew
  2. it overstresses the mast and changes the design load case Correct answer.
  3. it reduces the rated capacity shown on the load chart
  4. it increases the jib's lifting speed

Explanation

The crane is designed for a specific ballast amount and position, so extra counterweight increases compressive load on the mast and alters the moment balance the structure was designed for. Slew speed and hoist speed are controlled by the drives, not by ballast.

Question 22Site Preparation and Crane Setup

Before erection, mast sections, pins, and bolts must be checked for:

  1. compatibility with the assist crane's lifting capacity
  2. cracks, corrosion, deformation, and correct section match Correct answer.
  3. paint color and serial number sequence only
  4. weight and shipping labels

Explanation

A pre-erection inspection looks for structural damage such as cracks, heavy corrosion, bends, and elongation of pin holes, and confirms that the sections and pins are the correct matching parts. Cosmetic and shipping details are secondary to structural condition.

Question 23Site Preparation and Crane Setup

After erection and before handling a load, the crane must be:

  1. loaded to 100 percent of capacity to prove the chart
  2. re-grounded at the jib tip before use
  3. inspected, with limit and safety devices function tested Correct answer.
  4. run at full speed for one hour to break in the gears

Explanation

Commissioning requires a documented inspection and functional testing of limits, brakes, and safety devices before the crane goes into service. An uncontrolled full-capacity proof load is not a substitute for that process and may be hazardous.

Question 24Site Preparation and Crane Setup

When choosing between two otherwise acceptable base locations, which consideration best serves the operator?

  1. Placing the crane downwind of the work area
  2. Placing the crane as close to the building as possible
  3. Placing the crane where the jib can be made longest
  4. The location with the clearest view of the load Correct answer.

Explanation

Siting should maximize the operator's practical view of the load, the landing area, and the signal person, since blind lifts increase risk. Proximity to the building, jib length, and wind direction are separate decisions that do not substitute for visibility.

Question 25Site Preparation and Crane Setup

Before mobilizing, the delivery route for mast sections and counterweights must be checked for:

  1. the crane operator's driving record
  2. only the total driving distance from the supplier's yard
  3. load limits, width, turning radius, and overhead clearance Correct answer.
  4. the number of traffic signals along the route

Explanation

Oversize and heavy loads require a route survey covering bridge and pavement limits, lane and gate widths, corner radii, and overhead obstructions such as wires and bridges. Distance and signal counts do not establish whether the loads can physically pass.

Question 26Site Preparation and Crane Setup

Before excavation begins for a tower crane foundation, the site should be checked for:

  1. buried utilities and services Correct answer.
  2. the position of the site office
  3. the thickness of the surface pavement
  4. the color of the subsoil

Explanation

Underground services must be located and marked before any digging, because striking a gas main or electrical duct is a life-safety hazard and can also undermine the crane foundation. Utility records, drawings, and locating equipment are used to confirm the route of buried lines.

Question 27Site Preparation and Crane Setup

Erection work on a tower crane must stop when the wind speed at the site:

  1. reaches half of the crane's rated operating limit
  2. changes direction while a component is being lifted
  3. causes the jib to swing freely on its bearing
  4. exceeds the manufacturer's published erection limit Correct answer.

Explanation

Each manufacturer publishes a maximum wind speed for erection, climbing, and dismantling, and this figure is normally well below the in-service limit because the crane is incomplete and unstable during assembly. The wind speed is measured at the site, not assumed from a regional forecast.

Question 28Site Preparation and Crane Setup

A geotechnical investigation at the crane base location is carried out to establish:

  1. the crane's maximum free-standing height
  2. the delivery schedule for mast sections
  3. the number of counterweights required
  4. the soil bearing capacity and groundwater conditions Correct answer.

Explanation

Foundation design depends on how much load the ground can carry and where the water table sits, so borings and testing are used to determine bearing capacity and groundwater. The foundation must be sized so the actual soil can resist the crane's dead load and overturning moments.

Question 29Site Preparation and Crane Setup

A tower crane will be erected close to energized overhead power lines. The preferred first step is to:

  1. instruct the operator to work slowly near them
  2. post warning signs beneath the lines
  3. have the utility de-energize the lines Correct answer.
  4. install insulating blankets over the conductors

Explanation

The most reliable control is to remove the hazard by having the owner de-energize, relocate, or isolate the lines before the crane is assembled. Only if that cannot be done are other measures such as physical barriers, goalposts, and required clearances used.

Question 30Site Preparation and Crane Setup

Erection, climbing, and dismantling of a tower crane must be directed by:

  1. the crane operator assigned to the machine
  2. the site's general contractor or clerk of works
  3. any certified signal person on the crew
  4. a qualified person designated for that work Correct answer.

Explanation

The manufacturer's erection instructions require the work to be supervised by a person competent in that specific task, and the employer must designate that person. This person controls the sequence, verifies pinning and torque, and can stop the work when conditions change.

Question 31Site Preparation and Crane Setup

Mast sections delivered to the site should be stored:

  1. flat on bare ground near the excavation
  2. standing upright against the site fence
  3. stacked on the foundation slab
  4. on blocking, clear of the ground Correct answer.

Explanation

Mast sections stored on timber blocking stay dry, drain freely, and remain stable for slinging when the assist crane picks them up. Ground storage traps moisture at the bearing surfaces and can deform the connection faces and pins.

Question 32Site Preparation and Crane Setup

The minimum clearance between the counterjib and any fixed obstruction on site should be:

  1. one metre at the closest point
  2. as specified by the manufacturer Correct answer.
  3. equal to the length of the main jib
  4. whatever the operator judges to be safe

Explanation

The manufacturer's manual states minimum slewing clearances, because the jib and counterjib deflect under load and in wind, and the tower itself moves slightly in service. Working to the published figure ensures that structures, roofs, and adjacent cranes are never struck.

Question 33Site Preparation and Crane Setup

The electrical supply to a tower crane should be:

  1. taken from any convenient site outlet
  2. a dedicated circuit with a base disconnect Correct answer.
  3. run through an extension lead to the base
  4. shared with the site's welding equipment

Explanation

The crane needs a dedicated supply sized to the manufacturer's requirements, with a lockable isolating switch at the base so the machine can be safely de-energized for maintenance and inspection. Shared or improvised supplies create voltage drop and tripping hazards.

Question 34Site Preparation and Crane Setup

When deciding where to place the crane within the site, the heaviest and most frequent picks should be planned to occur:

  1. wherever the delivery truck can back in
  2. at the outer end of the jib radius
  3. as close to the mast as practical Correct answer.
  4. directly over the site entrance gate

Explanation

The crane's capacity falls as the load radius increases, so siting it near the main pick points keeps heavy loads well inside the chart and shortens cycle times. Unloading and pick positions are laid out around the crane, not the other way round.

Question 35Site Preparation and Crane Setup

A crane is to be founded on the structural slab of an underground car park. Before erection, the crane supplier must confirm that:

  1. the slab surface has been sealed
  2. the car park drains have been tested
  3. the slab has been swept and marked out
  4. the structure can carry the base loads Correct answer.

Explanation

A slab designed for parked cars has not been checked for the crane's base reactions, which include large overturning moments and concentrated punching loads. The building's engineer must verify capacity, and propping or a purpose-built foundation may be required.

Question 36Site Preparation and Crane Setup

For a crane that will be climbed as the building rises, the site layout must leave room at the base for:

  1. the operator's welfare cabin
  2. the site's material storage containers
  3. the concrete pump and its hopper
  4. the climbing frame and jacking equipment Correct answer.

Explanation

Climbing requires a climbing frame around the tower plus space to introduce and pin new mast sections using the assist crane. Congesting the base area makes each climb slower and can force the crane to be left at an unsafe height.

Question 37Site Preparation and Crane Setup

A spoil pile is to be placed about five metres from the crane foundation. The principal concern is that:

  1. the spoil will make the crane harder to see
  2. the spoil will need to be removed before dismantling
  3. the spoil adds surcharge loading near the base Correct answer.
  4. the spoil may trap water and rust the mast

Explanation

A stockpile acts as a surcharge that increases lateral earth pressure and can reduce the bearing capacity available under the foundation. The foundation design must account for such loads, or the pile must be kept outside the zone given by the designer.

Question 38Site Preparation and Crane Setup

Water collects in the base excavation before the concrete is placed. The correct action is to:

  1. place the concrete through the standing water
  2. pump the water out before placing concrete Correct answer.
  3. wait for the water to evaporate naturally
  4. add extra cement to the mix to compensate

Explanation

Concrete must not be placed into standing water, because the water washes cement from the mix and leaves a weak, porous foundation. The excavation is dewatered and the concrete placed in accordance with the foundation designer's specification.

Question 39Site Preparation and Crane Setup

While a tower crane is being erected, the area beneath and around the machine must be:

  1. barricaded against unauthorised entry Correct answer.
  2. manned only by the fuel bowser driver
  3. kept open to normal site traffic
  4. used for temporary storage of tools

Explanation

Erection creates a dropped-object hazard from pins, tools, and components, so a barricaded exclusion zone is set up and access is limited to the erection crew. The zone stays in place for climbing and dismantling as well.

Question 40Site Preparation and Crane Setup

A crane base would sit partly on undisturbed ground and partly on old fill. The primary risk is:

  1. the concrete will cure at different rates
  2. differential settlement of the foundation Correct answer.
  3. the crane will be noisier in operation
  4. the anchor bolts will be harder to align

Explanation

Fill and undisturbed ground compress by different amounts, so one edge of the foundation settles more than the other and tilts the whole tower. The resulting out-of-plumb condition induces loads the mast was never designed for, so such sites need an engineered foundation or removal of the fill.

Question 41Crane Assembly, Disassembly, and Climbing

Before erecting a tower crane, what is the main purpose of inspecting structural components such as mast and jib sections?

  1. To confirm the paint color matches the manufacturer's specification
  2. To establish the resale value of the components
  3. To decide which sections will be used as counterweight
  4. To find cracks, damage, or deformation that could weaken them Correct answer.

Explanation

Every structural component must be inspected before erection for cracks, corrosion, deformation, or shipping damage, and defective items are removed from service. The manufacturer's manual identifies the inspection points and rejection criteria for each component.

Question 42Crane Assembly, Disassembly, and Climbing

Which condition must be satisfied at the erection site before tower crane assembly begins?

  1. The trolley has been run out to the jib tip
  2. The crane's load chart has been posted in the operator's cab
  3. The ground can support the erection loads Correct answer.
  4. The counterweights have been painted and labeled

Explanation

The erection plan must confirm that the ground, foundation, or ballast mat can carry the crane and assisting-crane loads and that the base will end up level. Inadequate bearing capacity can cause settlement or collapse during assembly.

Question 43Crane Assembly, Disassembly, and Climbing

What governs the maximum wind speed at which a tower crane may be assembled, climbed, or dismantled?

  1. The preference of the crane operator
  2. The number of erectors on the crew
  3. The manufacturer's manual for the crane Correct answer.
  4. The local speed limit for road traffic

Explanation

Each manufacturer states a maximum permissible wind speed for erection, climbing, and dismantling in the crane's manual, and work stops when that value is reached. The wind is monitored at the relevant height throughout the operation.

Question 44Crane Assembly, Disassembly, and Climbing

Why must counterweights be installed in the quantity and sequence specified in the erection procedure?

  1. To increase the crane's maximum line pull
  2. To shorten the jib length
  3. To reduce the cost of the foundation
  4. To keep the crane balanced during erection Correct answer.

Explanation

Counterweights are part of the crane's stability system, and the procedure sequences them so the partly assembled crane stays balanced at every stage. Adding or omitting ballast at the wrong time changes the overturning moment on the mast and base.

Question 45Crane Assembly, Disassembly, and Climbing

Who is responsible for directing the assembly or disassembly of a tower crane on site?

  1. The site safety officer, regardless of crane experience
  2. The concrete supplier's supervisor
  3. Any rigger who has previously worked with cranes
  4. A qualified person designated to supervise the assembly Correct answer.

Explanation

Assembly and disassembly must be directed by a qualified person who is competent in that crane's procedures and authorized to supervise the operation. That person works from the manufacturer's manual and the site-specific erection plan.

Question 46Crane Assembly, Disassembly, and Climbing

What fall protection is required for erectors working at height on the crane structure?

  1. No protection if the work lasts under 15 minutes
  2. Only a hard hat and gloves
  3. Fall arrest or restraint with a suitable anchor point Correct answer.
  4. A safety net placed on the ground below

Explanation

Erectors at height must use a full body harness connected to fall arrest or fall restraint anchored to a suitable point, such as designated mast anchors or a climb-assist system. Short duration does not exempt anyone from fall protection.

Question 47Crane Assembly, Disassembly, and Climbing

After a tower crane has been erected and before it is placed in service, what must happen?

  1. The crane may be used for light loads only
  2. The operator may skip testing because the crane is new
  3. An inspection and function test are documented Correct answer.
  4. Only the jib needs to be checked

Explanation

An erected crane must be inspected and function-tested, including its limiters and limit switches, with the results recorded before any lifting. Many jurisdictions also require this verification by a competent or independent inspector.

Question 48Crane Assembly, Disassembly, and Climbing

What should the crew confirm before starting to dismantle a tower crane?

  1. That the crane has been fully loaded to test capacity
  2. That all limit switches have been bypassed
  3. That the jib has been extended to maximum length
  4. That the crane's setup matches the disassembly procedure Correct answer.

Explanation

Dismantling procedures are written for a specific configuration, so the crew must verify jib length, ballast, reeving, and tie-ins match what the procedure assumes. Removing components from an unexpected configuration can destabilize the crane.

Question 49Crane Assembly, Disassembly, and Climbing

A tower crane is to be tied to a building at several levels. Which statement about those ties is correct?

  1. Each tie must follow the manufacturer's or engineer's design Correct answer.
  2. Ties are needed only if the crane is taller than 30 m
  3. Ties can be replaced by adding extra counterweight
  4. Ties may be placed at any convenient floor using standard scaffold tube

Explanation

Tie-ins carry crane loads into the building structure, so each tie must use the specified tie frame, anchors, levels, and spacing worked out by the manufacturer or a qualified engineer. Untied free-standing height is separately limited by the manual.

Question 50Crane Assembly, Disassembly, and Climbing

During a climbing operation, what does the hydraulic climbing unit do?

  1. Lift the counterweights off the turntable
  2. Tension the pendant lines automatically
  3. Level the crane's foundation
  4. Raise the upper works to insert a new mast section Correct answer.

Explanation

The climbing unit pushes the slewing and upper structure up so the climbing frame opening is clear and a new mast section can be brought in, pinned, and bolted. The load is then transferred from the hydraulics to the mechanical supports.