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High Risk Work Licence - Slewing Mobile Crane C0 (over 100t) study materials
High Risk Work Licence - Slewing Mobile Crane C0 (over 100t) study resources

High Risk Work Licence - Slewing Mobile Crane C0 (over 100t) practice questions

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Question 1Legislative, regulatory and duty-of-care requirements

Under the model WHS Regulations, what is the primary duty of a person conducting a business or undertaking (PCBU) in relation to high risk work such as operating a slewing mobile crane over 100 tonnes?

  1. Guarantee that no incident can ever occur on the worksite
  2. Ensure the health and safety of workers and others so far as is reasonably practicable Correct answer.
  3. Delegate all safety obligations to the crane operator
  4. Provide insurance cover for any crane-related injury

Explanation

The primary duty of a PCBU is to ensure health and safety so far as is reasonably practicable, which includes providing a safe work environment, safe plant and structures, and safe systems of work. This duty is non-delegable and cannot be transferred to workers or insurers. It is measured by what is reasonably able to be done, not by an absolute guarantee.

Question 2Legislative, regulatory and duty-of-care requirements

A high risk work licence for a slewing mobile crane class C0 authorises the holder to operate which type of plant?

  1. Concrete placing booms on construction sites
  2. Slewing mobile cranes with a rated capacity over 100 tonnes Correct answer.
  3. Any crane with a boom length under ten metres
  4. Forklifts fitted with a jib attachment

Explanation

The C0 class covers slewing mobile cranes with a rated capacity exceeding 100 tonnes. Rated capacity is the maximum load the crane is designed to handle under specified conditions. Other plant such as concrete placing booms and forklift jibs fall under different licence classes or no licence requirement.

Question 3Legislative, regulatory and duty-of-care requirements

Which document sets out the general risk management process that a PCBU must follow when planning high risk crane work?

  1. The model WHS Regulations and accompanying code of practice Correct answer.
  2. The operator's personal logbook
  3. The site's social club newsletter
  4. The crane manufacturer's sales brochure

Explanation

The model WHS Regulations prescribe the risk management obligations, and the accompanying code of practice describes the recommended process of identifying hazards, assessing risks and implementing controls. Manufacturer information supports this but does not itself set the legal process. Logbooks and newsletters have no regulatory status for risk management.

Question 4Legislative, regulatory and duty-of-care requirements

A crane operator holds a current C0 licence but has not operated a crane of that capacity for two years. What is the most appropriate regulatory position before resuming work?

  1. No action is needed because licences never require currency of skill
  2. The operator must sit a completely new licence assessment
  3. The licence is automatically cancelled after twelve months of inactivity
  4. The licence remains valid, but the operator should be assessed as competent for the specific crane and task Correct answer.

Explanation

A high risk work licence remains valid until its expiry date, but the PCBU must ensure the operator is competent for the particular plant and task. Refresher training or a competency check is appropriate after a long period without operating. The licence alone does not prove current practical competence.

Question 5Legislative, regulatory and duty-of-care requirements

Who is responsible for ensuring that a crane operator's high risk work licence is verified as current before the operator starts work on site?

  1. The crane hire company's accountant
  2. The PCBU engaging the operator Correct answer.
  3. The local council parking inspector
  4. The crane operator alone

Explanation

The PCBU must ensure that workers hold the required licence and that it is verified, for example through the national licence verification service. This obligation sits with the person conducting the business or undertaking, not solely with the worker. Verification protects both the operator and others on site.

Question 6Legislative, regulatory and duty-of-care requirements

A crane is being set up near an overhead power line. Which regulatory requirement most directly applies to managing this hazard?

  1. Maintaining the safe approach distance and, where required, having the line de-energised or isolated Correct answer.
  2. Painting the crane a bright colour to improve visibility
  3. Requiring the operator to wear ear protection
  4. Increasing the crane's load chart capacity near the line

Explanation

Work near overhead power lines requires maintaining safe approach distances and, where that is not possible, arranging for the line to be de-energised or isolated with the network operator. These controls are specified in WHS regulations and guidance. Other measures do not address the electrical hazard itself.

Question 7Legislative, regulatory and duty-of-care requirements

What is the role of a safe work method statement (SWMS) for high risk construction work involving a large slewing mobile crane?

  1. It documents the hazards, risk controls and work sequence before work begins Correct answer.
  2. It replaces the need for any operator licence
  3. It is optional paperwork with no legal effect
  4. It is a financial invoice for crane hire

Explanation

A SWMS sets out the high risk construction work, the hazards, the risk control measures and how the work will be carried out. It must be prepared before work commences and be followed by workers. It does not substitute for licensing or other legal duties.

Question 8Legislative, regulatory and duty-of-care requirements

A worker on site notices that the crane's outrigger pads are sinking into soft ground. Under work health and safety law, what is the worker's obligation?

  1. Continue work and mention it at the end of the shift
  2. Report the hazard to the supervisor or PCBU as soon as practicable Correct answer.
  3. Adjust the load chart to compensate for the sinking
  4. Ignore it because only the supervisor is responsible

Explanation

Workers have a duty to take reasonable care of their own health and safety and that of others, and to report hazards and incidents. Reporting the sinking outriggers promptly allows the PCBU to implement controls such as mats or improved ground preparation. Delaying or ignoring the hazard increases the risk of tip-over.

Question 9Legislative, regulatory and duty-of-care requirements

Which of the following best describes the concept of 'reasonably practicable' when determining controls for crane operations?

  1. Applying controls only after an incident has occurred
  2. Weighing the likelihood and severity of harm against the cost, time and effort of available controls Correct answer.
  3. Doing whatever is cheapest regardless of risk
  4. Relying solely on the operator's experience

Explanation

Reasonably practicable involves weighing the likelihood and degree of harm against the availability, suitability, cost and effort of controls. It is an objective test that favours safety where the risk is significant and controls are available. It does not permit choosing the cheapest option when serious harm is likely.

Question 10Legislative, regulatory and duty-of-care requirements

A PCBU is planning to use a 120-tonne slewing mobile crane for a lift near a public footpath. Which notification obligation is most likely to apply?

  1. Notify the regulator of the high risk construction work where required by regulation Correct answer.
  2. Notify the operator's family of the work schedule
  3. Notify the crane manufacturer of the lift
  4. No notification is required because the crane is on private land

Explanation

Certain high risk construction work must be notified to the regulator before it commences, and work involving plant near public areas may trigger notification. The PCBU must check the applicable regulations and notify as required. Notification is separate from licensing and does not replace other duties.

Question 11Legislative, regulatory and duty-of-care requirements

What does the 'hierarchy of control' require a PCBU to do when managing crane-related risks?

  1. Choose controls based on worker preference alone
  2. Always rely on personal protective equipment as the first option
  3. Use administrative controls before engineering controls
  4. Apply the highest level of control reasonably practicable, starting with eliminating the risk Correct answer.

Explanation

The hierarchy of control ranks measures from eliminating the hazard through substitution, engineering controls, administrative controls and finally PPE. PCBU s must work through the hierarchy and apply the highest level reasonably practicable. PPE is the least reliable and is a last line of defence.

Question 12Legislative, regulatory and duty-of-care requirements

An operator is directed by a site manager to lift a load that exceeds the crane's rated capacity. What is the operator's most appropriate response under WHS law?

  1. Perform the lift but reduce the boom angle
  2. Perform the lift only if no one is watching
  3. Comply because the site manager has authority
  4. Refuse the lift and report the unsafe direction Correct answer.

Explanation

An operator must not perform work that is unsafe, and a direction to exceed rated capacity is unlawful and dangerous. The operator should refuse the lift and report the unsafe direction to the PCBU. Workers are protected from adverse action for refusing unsafe work.

Question 13Legislative, regulatory and duty-of-care requirements

Which of the following is an example of a duty owed by a crane operator to other persons at the workplace?

  1. Guaranteeing the financial profitability of the project
  2. Purchasing the crane on behalf of the PCBU
  3. Designing the site layout for all trades
  4. Taking reasonable care that their acts or omissions do not adversely affect others' health and safety Correct answer.

Explanation

Workers, including crane operators, must take reasonable care for their own safety and that of others, and must not adversely affect others through their acts or omissions. This duty operates alongside the PCBU's primary duty. It does not extend to commercial or procurement responsibilities.

Question 14Legislative, regulatory and duty-of-care requirements

A crane operator's licence has expired but the operator continues to perform high risk work. What is the most accurate description of the legal position?

  1. Only the crane owner can be prosecuted
  2. The operator is committing an offence and the PCBU may also be liable for allowing unlicensed work Correct answer.
  3. The work is lawful if the lift is small
  4. The work is lawful because the operator is experienced

Explanation

Performing high risk work without a current licence is an offence, and the PCBU that permits unlicensed work may also breach its duties. Experience does not substitute for a valid licence. Liability can extend to multiple duty holders, not only the owner.

Question 15Legislative, regulatory and duty-of-care requirements

What is the purpose of consulting with workers when developing safe systems of work for crane operations?

  1. To reduce the number of safety inspections required
  2. To draw on workers' knowledge and improve the effectiveness of risk controls Correct answer.
  3. To satisfy a purely decorative administrative step
  4. To shift legal liability entirely onto the workers

Explanation

Consultation is a legal duty that draws on workers' practical knowledge to identify hazards and improve controls. It also builds commitment to safe systems of work. Consultation does not transfer the PCBU's liability to workers or remove inspection obligations.

Question 16Legislative, regulatory and duty-of-care requirements

A crane is to be used to lift personnel in a work box. Which regulatory consideration is most relevant?

  1. Personnel lifting requires no additional planning
  2. Personnel lifting is permitted only where it is the least risk option and specific controls are in place Correct answer.
  3. Personnel lifting can be done using any load chart setting
  4. Personnel lifting is always prohibited without exception

Explanation

Lifting personnel in a work box is high risk and is permitted only where it is the least risk option and where specific controls, such as a designed work box and a suitable crane, are in place. It requires careful planning and compliance with guidance. It is not automatically prohibited, but it is tightly controlled.

Question 17Hazard identification, risk assessment and control

Before a lift begins, which document defines the crane's rated capacity for a specific boom length, radius and configuration?

  1. The load chart issued for that crane model and configuration Correct answer.
  2. The site induction booklet
  3. The crane's service logbook
  4. The daily pre-start checklist

Explanation

Rated capacity is determined only from the load chart applicable to the exact boom length, radius, counterweight and outrigger configuration in use. The chart already accounts for structural and stability limits, so no other document can substitute for it.

Question 18Hazard identification, risk assessment and control

A slewing mobile crane is set up on compacted fill beside an excavation. Which control best manages the risk of ground bearing failure under an outrigger?

  1. Using spreader mats sized to the outrigger load Correct answer.
  2. Increasing engine speed during the lift
  3. Adding counterweight to stabilise the crane
  4. Slewing more slowly while carrying the load

Explanation

Outrigger loads are concentrated and can exceed the bearing capacity of fill or backfill near an excavation. Spreader mats or pads distribute the load over a larger area and are sized from the calculated outrigger reaction.

Question 19Hazard identification, risk assessment and control

What is the primary purpose of a risk assessment before a crane lift?

  1. To calculate the hire cost of the crane
  2. To satisfy the client's paperwork requirements
  3. To identify hazards and decide controls before work starts Correct answer.
  4. To record the crane operator's qualifications

Explanation

A risk assessment systematically identifies the hazards of the task, evaluates how likely and severe harm could be, and sets out controls to reduce risk so far as reasonably practicable. It is a decision-making tool, not a record-keeping exercise.

Question 20Hazard identification, risk assessment and control

During a lift, the operator notices the crane's rated capacity indicator approaching its limit at a long radius. What is the correct immediate action?

  1. Stop the lift and reassess the lift plan Correct answer.
  2. Ask the dogger to walk the load faster
  3. Continue and monitor the indicator closely
  4. Reduce boom length while holding the load

Explanation

Approaching the rated capacity at a long radius means the lift is close to the structural or stability limit, where small dynamic effects can overload the crane. The lift should stop and the plan be reassessed, for example by reducing radius or using a larger crane.

Question 21Hazard identification, risk assessment and control

Which factor most directly increases the radius at which a slewing mobile crane can safely lift a given load?

  1. Retracting the boom to a shorter length Correct answer.
  2. Slewing the crane more quickly
  3. Increasing the load mass to improve stability
  4. Raising the boom angle to vertical

Explanation

Retracting the boom shortens the distance from the slew centre to the load, reducing radius and allowing a higher capacity to be used. Capacity falls as radius increases, so reducing radius is the standard way to lift more at a safe margin.

Question 22Hazard identification, risk assessment and control

Which hazard is specific to lifting near an overhead powerline with a slewing mobile crane?

  1. Vibration transmitted through the outriggers
  2. Exhaust emissions from the crane engine
  3. Contact or approach arcing between the crane and live conductors Correct answer.
  4. Arc flash from the crane's own electrical system

Explanation

The main hazard near overhead lines is the crane structure, boom or load approaching live conductors closely enough for electricity to arc across the air gap. Exclusion zones and spotter control are used to keep the required clearance.

Question 23Hazard identification, risk assessment and control

A crane is lifting a load with a large surface area on a windy day. Which effect should the risk assessment address?

  1. Lower ground bearing pressure
  2. Reduced hydraulic oil temperature
  3. Increased wind load on the load and boom Correct answer.
  4. Faster rope wear on the hoist drum

Explanation

Wind acting on a large sail area produces significant force on the load and boom, increasing radius, dynamic loading and the risk of losing control. Load charts often specify maximum wind speeds, and the assessment should set a stop-work threshold.

Question 24Hazard identification, risk assessment and control

Two cranes are required to lift a single load in tandem. Which control is most important before the lift?

  1. A documented tandem lift plan with load share and communication defined Correct answer.
  2. Requiring both operators to use the same radio channel only
  3. Lifting the load with one crane and using the second as a counterweight
  4. Ensuring both cranes have identical load charts

Explanation

Tandem lifts need a written plan that allocates load share between cranes, accounts for the effect of load transfer, and defines a single person in control and clear communication. Each crane must remain within its own capacity throughout the move.

Question 25Hazard identification, risk assessment and control

What is the main risk created by lifting a load whose centre of gravity is offset from the rigging point?

  1. The hoist rope will shorten
  2. The load may tilt or swing and the slings may be unequally loaded Correct answer.
  3. The outriggers will retract
  4. The crane's hydraulic system will overheat

Explanation

An offset centre of gravity causes the load to hang out of level, shifting the effective radius and placing unequal tension on slings. The lift plan should identify the centre of gravity and use rigging that keeps the load level and stable.

Question 26Hazard identification, risk assessment and control

Which is the most effective control for the hazard of personnel being struck by a slewing crane's superstructure?

  1. Warning personnel with a whistle
  2. Requiring high-visibility clothing only
  3. Excluding personnel from the slew zone with barriers and signage Correct answer.
  4. Slewing only when the operator sounds the horn

Explanation

The hierarchy of control favours isolating people from the hazard over administrative measures. Physical barriers and marked exclusion zones keep personnel out of the path of the counterweight and superstructure.

Question 27Hazard identification, risk assessment and control

A crane's load moment limiter is found to be faulty during the pre-start check. What is the correct response?

  1. Borrow a limiter from another crane
  2. Use the crane only for short lifts
  3. Operate at reduced capacity and log the fault
  4. Tag the crane out of service until the fault is repaired Correct answer.

Explanation

The load moment limiter is a critical safety device that warns of and prevents overload, and a crane with a faulty limiter must not be used. It should be locked out and repaired by a competent person before returning to service.

Question 28Hazard identification, risk assessment and control

Why is a soft-start and smooth-stop technique important when lifting a heavy load?

  1. It prevents the hoist rope from twisting
  2. It limits dynamic load and load swing that can exceed rated capacity Correct answer.
  3. It keeps the outriggers from settling
  4. It reduces fuel consumption on the crane

Explanation

Sudden starts and stops add dynamic forces to the static load and can set the load swinging, increasing effective radius and stress on the crane. Smooth control keeps the load within the assumed conditions of the load chart.

Question 29Hazard identification, risk assessment and control

A crane is working on a site with a known underground void near the outrigger position. Which action best manages the risk?

  1. Assume the void will not affect the outrigger
  2. Use the crane in a lower boom configuration
  3. Assess the ground and relocate or bridge the outrigger Correct answer.
  4. Increase counterweight to stabilise the crane

Explanation

A void under an outrigger can collapse under load and cause the crane to overturn. A competent person should assess the ground, and the outrigger should be relocated or supported by bridging or a designed pad.

Question 30Hazard identification, risk assessment and control

Which factor is most likely to reduce a crane's effective capacity when lifting across the side of the machine rather than over the front?

  1. The operator's view is improved
  2. The hoist rope is shorter in that direction
  3. The load chart is not applicable to side lifts
  4. The structural strength of the boom and slew ring is lower in that direction Correct answer.

Explanation

Many slewing mobile cranes have different capacities depending on the working area, because boom and slew ring strength and stability vary. The load chart must be read for the correct working area, and side lifts often give lower ratings.

Question 31Hazard identification, risk assessment and control

A lift plan specifies a two-leg sling with a 60-degree included angle. What is the main reason for controlling the sling angle?

  1. To limit the tension in each leg and the compression in the load Correct answer.
  2. To make the hook block hang lower
  3. To keep the load level in the wind
  4. To reduce the crane's hydraulic pressure

Explanation

As the included angle between sling legs increases, the tension in each leg rises sharply for the same load, and horizontal compression on the load also increases. Keeping the angle within a safe range prevents sling overload and load damage.

Question 32Hazard identification, risk assessment and control

What is the purpose of a hazard exclusion zone around a slewing mobile crane during operation?

  1. To show the extent of the crane's warranty
  2. To keep people out of areas where they could be struck or crushed Correct answer.
  3. To define where the crane may refuel
  4. To mark the crane's parking bay

Explanation

An exclusion zone is a physical or marked boundary that keeps people away from the slew path, the load path and any area where a load could fall. It is a key isolation control for pedestrians and other workers.

Question 33Hazard identification, risk assessment and control

A crane lift is planned near a public road. Which combination of controls best addresses the risk to the public?

  1. Using a larger crane than necessary
  2. A sign at the site gate and a radio for the dogger
  3. A traffic management plan, exclusion zones and a time window for the lift Correct answer.
  4. Lifting only during daylight hours

Explanation

Public protection requires a traffic management plan to separate vehicles and pedestrians, exclusion zones under the load path, and often a planned time window to minimise exposure. These controls work together to isolate the public from the hazard.

Question 34Hazard identification, risk assessment and control

During a lift, the load begins to swing toward a nearby structure. Which action is the most appropriate immediate response?

  1. Stop the hoist and slew, and control the swing with the tag line Correct answer.
  2. Lower the load onto the structure
  3. Increase hoist speed to clear the structure
  4. Slew quickly away from the structure

Explanation

Swing is controlled by stopping the motion that induced it and using the tag line to damp the movement before resuming. Rapid or aggressive corrections add dynamic load and can worsen the swing.

Question 35Hazard identification, risk assessment and control

A risk assessment for a crane lift identifies a hazard with a high likelihood and severe consequence that cannot be eliminated. What does the hierarchy of control require next?

  1. Rely on personal protective equipment as the primary control
  2. Rely on worker training alone
  3. Accept the risk because it cannot be eliminated
  4. Apply engineering controls such as guarding or interlocks before administrative controls Correct answer.

Explanation

The hierarchy of control ranks elimination highest, followed by substitution, engineering controls, administrative controls and finally PPE. Where elimination is not possible, engineering controls that reduce risk at the source should be applied before relying on procedures or PPE.

Question 36Hazard identification, risk assessment and control

A crane is set up on a slope. Which effect on the lift is most significant?

  1. The load chart may not apply and the crane is more prone to overturning Correct answer.
  2. The hoist rope becomes stronger
  3. The slew motor runs cooler
  4. The crane's rated capacity increases because of gravity

Explanation

Load charts assume the crane is level; on a slope the geometry changes, outrigger loads become uneven and the crane is more prone to overturning. The crane must be set up level within the manufacturer's tolerance, using packing under the floats if needed.

Question 37Crane types, configurations and load charts for cranes over 100t

On a slewing mobile crane rated above 100 tonnes, what does the term 'configuration' refer to when preparing to lift?

  1. The specific combination of boom length, jib, counterweight and outrigger setup in use Correct answer.
  2. The number of operators rostered for the shift
  3. The colour scheme and company branding applied to the crane body
  4. The fuel type and engine rating of the carrier vehicle

Explanation

Configuration means the exact physical arrangement of boom, jib, counterweight, outriggers and superlift that the load chart was calculated for. Each change to that arrangement produces a different capacity, so the chart must match the crane as assembled.

Question 38Crane types, configurations and load charts for cranes over 100t

A crane's load chart shows a rated capacity that already includes a deduction for the hook block and lifting gear. What is this value commonly called?

  1. Structural limit
  2. Gross capacity
  3. Rated capacity after deduction
  4. Net capacity Correct answer.

Explanation

Net capacity is the rated capacity minus the weight of hook block, slings and other lifting gear that hangs below the boom point. The load itself must not exceed this net figure.

Question 39Crane types, configurations and load charts for cranes over 100t

Why do load charts for cranes over 100 tonnes typically show capacity falling sharply as radius increases?

  1. Because hydraulic pressure drops at longer boom extensions
  2. Because rope wear accelerates at longer radii
  3. Because wind speed always rises with lifting height
  4. Because the load moment on the boom and the tipping moment on the base both increase with radius Correct answer.

Explanation

Capacity is governed by the moment created by load multiplied by radius. As radius grows, both structural stress on the boom and overturning moment on the base rise, so allowable load falls.

Question 40Crane types, configurations and load charts for cranes over 100t

Which document must be consulted to confirm the capacity of a specific crane at a specific radius and boom length?

  1. The operator's licence card
  2. The crane's service logbook
  3. The manufacturer's load chart for that exact configuration Correct answer.
  4. The site traffic management plan

Explanation

Only the manufacturer's load chart for the exact configuration gives the rated capacity at a given radius and boom length. Other documents support planning but do not state capacity.

Question 41Crane types, configurations and load charts for cranes over 100t

What is the purpose of outrigger mats or spreader pads under a large mobile crane?

  1. To raise the crane so the boom clears site fencing
  2. To level the crane regardless of ground slope
  3. To reduce the crane's overall transport weight
  4. To spread the outrigger load over a larger area and reduce ground bearing pressure Correct answer.

Explanation

Spreader pads increase the contact area so the outrigger force is distributed and ground bearing pressure is reduced. This helps prevent penetration or collapse of the supporting surface.

Question 42Crane types, configurations and load charts for cranes over 100t

Which of the following best describes 'boom length' as it appears on a load chart?

  1. The height of the crane's cab above ground
  2. The distance between the front and rear outriggers
  3. The horizontal distance from the slew centre to the hook
  4. The actual length of boom sections extended and pinned for the lift Correct answer.

Explanation

Boom length is the physical length of boom assembled and extended, and it is one of the two main inputs, with radius, to reading a load chart. Different boom lengths have different capacity curves.

Question 43Crane types, configurations and load charts for cranes over 100t

When a crane is configured with a luffing jib, what additional information does the chart provide compared with a fixed jib?

  1. Capacity for various jib angles and radii Correct answer.
  2. Only the maximum hook height
  3. The counterweight removal procedure
  4. The crane's road speed

Explanation

A luffing jib can be raised and lowered to change radius, so its chart gives capacities across a range of jib angles and corresponding radii. A fixed jib has a single geometry per mounting.

Question 44Crane types, configurations and load charts for cranes over 100t

What should an operator do if the actual lifting radius is between two values shown on the load chart?

  1. Use the capacity for the longer radius Correct answer.
  2. Average the two capacities
  3. Estimate the capacity by interpolation
  4. Use the capacity for the shorter radius

Explanation

Capacity must always be taken at the next longer radius shown, because the true capacity at the intermediate radius is lower than at the shorter value. Averaging or interpolating can overstate capacity.

Question 45Crane types, configurations and load charts for cranes over 100t

A crane configured with full counterweight is charted at 40 tonnes at 18 m radius. The same crane with reduced counterweight is charted at 32 tonnes at the same radius. What is the most likely reason for the difference?

  1. The reduced counterweight lowers the crane's resistance to overturning Correct answer.
  2. The hook block was removed
  3. The boom was shortened for the second lift
  4. The wind speed increased

Explanation

Counterweight increases the restoring moment that resists tipping, so less counterweight means a lower overturning resistance and therefore a lower charted capacity at the same radius. The boom length and radius are stated as unchanged.

Question 46Crane types, configurations and load charts for cranes over 100t

An operator is lifting a 12 tonne load at 30 m radius. The chart for the current configuration shows 14 tonnes at 30 m. The hook block and slings weigh 1.5 tonnes. What is the correct conclusion?

  1. The lift is acceptable because 12 tonnes is below 14 tonnes
  2. The lift exceeds capacity because gross load is 13.5 tonnes Correct answer.
  3. The lift is acceptable if wind is below 10 m/s
  4. The lift is acceptable because the gear is included in the chart

Explanation

The hook block and slings must be added to the load to give the gross load the crane actually carries. Here 12 plus 1.5 equals 13.5 tonnes, which is below 14 tonnes, so it is within capacity, but the correct reasoning is that gross load must be compared.

Question 47Crane types, configurations and load charts for cranes over 100t

A 130 tonne crane is set up on outriggers with a chart for 360 degree slew. The supervisor asks the operator to work over the side only to gain capacity. What is the correct response?

  1. The crane can lift any load if it slews slowly
  2. Side capacity is higher so the change is safe
  3. Slew restriction always reduces capacity
  4. The chart in use already governs; a different chart must be selected and verified before using a higher side rating Correct answer.

Explanation

Some charts give higher capacities over the side or rear than over the front, but only when the crane is configured and set up for that chart. The operator must confirm the correct chart applies before relying on a higher rating.

Question 48Crane types, configurations and load charts for cranes over 100t

What does the term 'tipping capacity' refer to on a mobile crane load chart?

  1. The load at which the crane's structure fails
  2. The load that causes the boom to bend
  3. The maximum load the hook can hold
  4. The load at which the crane would begin to overturn about its support points Correct answer.

Explanation

Tipping capacity is the load that would cause the crane to overturn about its outrigger or track support line. Charts apply a safety margin below this value to give rated capacity.

Question 49Crane types, configurations and load charts for cranes over 100t

Why must a crane's load chart be specific to the serial number or model variant of the crane being operated?

  1. Because serial numbers are needed for invoicing
  2. Because charts are revised over time and different variants have different capacities Correct answer.
  3. Because all cranes of the same size share one chart
  4. Because operators prefer personalised charts

Explanation

Manufacturers issue revised charts and different variants may have different boom sections, counterweights or ratings. Using the chart that matches the exact crane ensures the stated capacities are valid.

Question 50Crane types, configurations and load charts for cranes over 100t

A crane is configured with a fly jib. How does this typically affect capacity compared with the main boom alone at the same radius?

  1. Capacity is unchanged
  2. Capacity depends only on the hook
  3. Capacity increases because the jib adds length
  4. Capacity decreases because the jib adds weight and reduces structural margin Correct answer.

Explanation

A fly jib adds dead weight and changes the load path, reducing the capacity available at a given radius. Charts for the jib configuration reflect this reduction.