Free Red Seal Mobile Crane Operator Examination Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Red Seal Mobile Crane Operator Examination practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1While directing a truck-mounted telescoping crane, a signaller holds both fists in front of the body with the thumbs pointing toward each other. Under the CCOHS common hand signals for this crane, what movement is requested?

   1. A.Extend boom
   2. B.Lower boom
   3. C.Retract boomCorrect answer: C
   4. D.Raise boom

   Explanation: CCOHS describes the retract-boom signal as "Both fists in front of body with thumbs pointing toward each other." The inward-pointing thumbs request retraction; outward-pointing thumbs request extension.

   Reference: CCOHS Materials Handling - Crane and Hoist Hand Signals — What are some common hand signals for crawler, truck and locomotive cranes?

2. 2Before a lift, a mobile-crane operator must estimate the weight of a solid rectangular concrete block. Its dimensions are 2 m by 1.5 m by 0.5 m, and its unit weight is 2,400 kg/m³. Ignoring rigging and attachments, what is the block's weight?

   1. A.1,800 kg
   2. B.2,400 kg
   3. C.3,600 kgCorrect answer: C
   4. D.7,200 kg

   Explanation: NIST gives rectangular volume as "length × width × depth", and the Red Seal standard states that the "calculation is: volume times unit weight of material". The block volume is 2 × 1.5 × 0.5 = 1.5 m³, so its weight is 1.5 m³ × 2,400 kg/m³ = 3,600 kg. The alternatives result from mistakenly treating the rectangular cross-section as triangular and halving it (1,800 kg), omitting the 1.5 m dimension (2,400 kg), or omitting the 0.5 m dimension (7,200 kg).

   Reference: Red Seal Occupational Standard – Mobile Crane Operator — Task B-3, subtask B-3.02, printed pages 38–39

3. 3During a pre-operational check on a mobile crane with an air-brake system, the operator observes the compressor stop pumping when normal reservoir pressure is reached. Which component controls this normal cut-out?

   1. A.Air dryer
   2. B.Air governorCorrect answer: B
   3. C.Safety valve
   4. D.One-way check valve

   Explanation: Ontario's air-brake handbook states that "The governor controls the air compressor cut-in and cut-out pressure." The dryer removes moisture, the check valve prevents reverse airflow, and the safety valve releases excess pressure if the governor fails.

   Reference: Ontario Official Air Brake Handbook, Air Supply Subsystem — Key points, air-supply subsystem

4. 4To stabilize a component, a rigger places two separate single-wrap choker slings around it, spaced apart from one another. What hitch configuration is this?

   1. A.Single choker hitch
   2. B.Double choker hitchCorrect answer: B
   3. C.Double wrap choker hitch
   4. D.Double basket hitch

   Explanation: CCOHS describes a double choker hitch as using "two slings in a choker hitch that are spread to provide stability". It is distinct from a single choker, a double-wrap choker and a basket arrangement.

   Reference: CCOHS Materials Handling – Rigging or Sling Hitches — How should you use choker hitches? Double choker hitch

5. 5A crew is positioning a mobile crane in British Columbia beside a fixed wall. Workers will be able to enter the space between the wall and a moving part of the crane. Under section 14.41, what is the minimum clearance that the positioning must provide?

   1. A.0.6 metresCorrect answer: A
   2. B.0.9 metres
   3. C.2.0 metres
   4. D.3.0 metres

   Explanation: Section 14.41(1) requires that no moving part come "within 60 cm (2 ft) of any obstruction in any area accessible to workers". Thus the minimum clearance is 0.6 m. Larger clearances meet the stated minimum but are not the minimum specified. If the clearance cannot be provided, subsection (2) requires access to the area to be prevented.

   Reference: British Columbia Occupational Health and Safety Regulation, Part 14 — Section 14.41(1)–(2)

6. 6A crew secures a 7.0 m crane component on an Ontario commercial vehicle. Each weight and rating described in section 4 of Regulation 363/04 is 4,500 kg or less, and no conflicting permit applies. If using the tie-down method in section 5(1)(b), what is the minimum number of tie-downs required by its length rule alone?

   1. A.1 tie-down
   2. B.2 tie-downs
   3. C.3 tie-downsCorrect answer: C
   4. D.4 tie-downs

   Explanation: Section 5(1)(b) requires "at least one tiedown" for "each 3.04 linear metres of lading or fraction thereof". The length calculation is 7.0 ÷ 3.04 = 2.30, which rounds up to 3 tie-downs. One or two would leave a full interval or fraction uncovered; four exceeds this length-only minimum. Additional tie-downs may be needed to secure the load.

   Reference: Ontario Regulation 363/04, Security of Cargo — Sections 4 and 5(1)(b)

7. 7An operator sets up an electronic aid that compares the crane's sensed overturning moment with its rated capacity and displays the percentage of capacity being used. Which aid is this?

   1. A.Load-weight indicator
   2. B.Load-moment indicatorCorrect answer: B
   3. C.Load-moment limiter
   4. D.Anti-two-block system

   Explanation: OSHA defines the load-moment indicator as a system that "compares this lifting condition to the equipment's rated capacity" and displays the percentage in use. A load-moment limiter has the different function of shutting off specified movements at rated capacity; the other devices monitor load weight or two-block conditions.

   Reference: OSHA Cranes and Derricks in Construction, Definitions — 29 CFR 1926.1401, Load moment (or rated capacity) indicator

8. 8A mobile-crane operator in British Columbia is working near an exposed 25 kV phase-to-phase overhead conductor. The crane is not merely passing underneath it, and no exception under the electrical safety rules applies. What is the minimum approach distance for the crane?

   1. A.2 metres
   2. B.3 metresCorrect answer: B
   3. C.4.5 metres
   4. D.6 metres

   Explanation: Table 19-1A places "Over 750 V to 75 kV" in the 3-metre minimum approach category. At 25 kV, the ordinary working-near rule therefore requires a minimum of 3 metres. The 2-metre figure is for passing under in the corresponding voltage band; 4.5 and 6 metres apply to higher bands.

   Reference: British Columbia Occupational Health and Safety Regulation, Part 19 — Section 19.24.1 and Table 19-1A

9. 9For a mobile-crane lift in British Columbia, a sling leg is 40° from vertical. The rigger is using the WLL reduction table in the provincial regulation rather than a separately determined manufacturer or qualified-person reduction. To what percentage of the sling's WLL does the table reduce it?

   1. A.50%
   2. B.70%Correct answer: B
   3. C.75%
   4. D.90%

   Explanation: Table 15-3 assigns "over 30° up to 45°" a reduction to "70%" of WLL. At 40° from vertical, the leg falls in that band. The table's adjacent bands use 90% and 50%; 75% is associated with the CCOHS choker-hitch guidance, not this angle band.

   Reference: British Columbia Occupational Health and Safety Regulation, Part 15 — Section 15.34 and Table 15-3

10. 10A crane operator reviews the operating history of a hoist rope that repeatedly bends over sheaves during normal service. Which deterioration mechanism is caused by that repeated bending?

    1. A.Corrosion
    2. B.Crushing
    3. C.FatigueCorrect answer: C
    4. D.Kinking

    Explanation: CCOHS identifies "Fatigue from repeated bending even under normal operating conditions." Corrosion, crushing and kinking are different types of wire-rope damage with different causes or forms.

    Reference: CCOHS Materials Handling - Hoist Wire Rope — What can cause a wire rope to break?