20 Signals & Communication Practice Questions & Answers

1. 1. A worker on the ground extends BOTH arms horizontally to the side, palms down, and swings both arms back and forth. What is this standard hand signal telling the mobile crane operator?

   • A.Dog everything — suspend operations and hold as-is
   • B.Emergency stop — halt all crane motion immediately✓ Answer
   • C.Travel — move the crane in the direction indicated
   • D.Ordinary stop — end only the function currently in motion

   In the standard method the ordinary STOP is given with ONE arm extended horizontally, palm down, swung back and forth; doubling that motion with BOTH arms is the EMERGENCY STOP. The number of arms is the only thing that separates them, which is why it is the most-drilled discrimination in the signal set, and the operator must obey a stop or emergency stop signal no matter who gives it.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); ASME B30.5, Mobile and Locomotive Cranes, signals sectionReport a problem with this question

2. 2. A signal person extends one arm horizontally to the side with the thumb pointing DOWN while the other fingers repeatedly open and close. What is being commanded?

   • A.Lower the boom only, at reduced speed
   • B.Raise the boom while lowering the load
   • C.Lower the load only, using the auxiliary line
   • D.Lower the boom while raising the load✓ Answer

   The thumb sets the boom's direction — thumb down means boom down — and opening and closing the fingers adds load-line movement in the opposite sense, so the hook rises while the boom comes down. The mirror image, thumb UP with fingers opening and closing, means boom up and lower the load; candidates invert these because the load always moves opposite the thumb.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); ASME B30.5, Mobile and Locomotive Cranes, signals sectionReport a problem with this question

3. 3. On a crawler crane the signal person raises the fist on the left side and rotates the right fist in front of the body. What does this signal mean?

   • A.Travel both tracks forward together
   • B.Lock the left track and travel the right track in the direction the rotating fist turns✓ Answer
   • C.Swing the upperworks to the left
   • D.Travel the left track in the direction shown and lock the right track

   In the standard crawler-crane signal the RAISED fist marks the track that is to be LOCKED, not the track that moves; the rotating fist shows both which track travels and its direction. Reading the raised fist as the moving track is a near-universal error and would steer the machine the wrong way.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); ASME B30.5, Mobile and Locomotive Cranes, signals sectionReport a problem with this question

4. 4. A signal person rotates both fists around each other in front of the body, with the rotation turning TOWARD the body. On a crawler crane, what is commanded?

   • A.Swing right and stop
   • B.Dog everything
   • C.Travel both tracks backward✓ Answer
   • D.Travel both tracks forward

   The travel-both-tracks signal uses the direction of fist rotation to set the direction of travel: rotation toward the body means forward, rotation away from the body means backward. The signal is specific to crawler cranes, which steer by driving the two tracks independently.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); ASME B30.5, Mobile and Locomotive Cranes, signals sectionReport a problem with this question

5. 5. A signal person bends one arm at the elbow so the forearm is vertical, taps that elbow with the other hand, and then gives a hoist signal. What has the operator been told to do?

   • A.Select the whipline (auxiliary hoist), then hoist on that line✓ Answer
   • B.Stop hoisting — an anti-two-block warning
   • C.Hoist slowly on whichever line is already reeved
   • D.Select the main hoist, then hoist on that line

   Tapping the elbow with the forearm vertical selects the whipline or auxiliary hoist, while tapping the top of the head selects the main hoist. Either one is only a selection signal, so it is always followed by the regular action signal that tells the operator what to do with the chosen line; in voice signalling neither 'use whipline' nor 'use main hoist' has a terminate command.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); CCO Signalperson Reference Manual, acceptable voice signal terminologyReport a problem with this question

6. 6. A signal person holds one fist in front of the chest and taps the chest with the THUMB. On a telescopic-boom mobile crane, what does this one-hand signal command?

   • A.Move slowly — reduce the speed of the current function
   • B.Boom up — raise the boom
   • C.Telescope in — retract the boom
   • D.Telescope out — extend the boom✓ Answer

   The one-hand telescoping pair is told apart by what touches the chest: the THUMB tapping the chest means telescope out, while the HEEL of the fist tapping the chest with the thumb pointing outward means telescope in. These one-hand versions come from the ASME mobile-crane signal chart rather than the OSHA appendix, which shows only the two-hand versions — where the federal rule does not address a signal, the ASME chart is the reference.

   Source: ASME B30.5, Mobile and Locomotive Cranes, standard hand signals; OSHA 29 CFR 1926 Subpart CC, Appendix AReport a problem with this question

7. 7. In the standard hand signal for swing, the signal person extends an arm horizontally and points with the index finger. What does the pointing finger indicate?

   • A.The track that is to be locked
   • B.The direction the signal person is about to walk
   • C.The direction in which the boom is to swing✓ Answer
   • D.The point on the ground where the load is to be set down

   The swing signal points the index finger in the direction the BOOM is to swing, not at a landing point and not in the direction the signal person happens to be facing. Like every other direction given to the operator, it is expressed from the operator's direction perspective, which is what keeps it unambiguous when the signal person is facing the machine.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); OSHA 29 CFR 1926.1419, Signals — general requirementsReport a problem with this question

8. 8. A signal person holds both hands together at waist level. What does this signal mean, and how does it differ from stop?

   • A.Dog everything — suspend all operations and hold as-is; unlike stop it is a hold command with no voice terminate signal✓ Answer
   • B.Move slowly — continue the current function at reduced speed
   • C.Telescope in — retract the boom to the stowed length
   • D.Emergency stop — kill every crane motion at once

   Hands held together at waist level is the dog-everything signal: it tells the operator to suspend operations and hold everything where it is. It is routinely confused with STOP, which is one arm extended horizontally, palm down, swung back and forth, and which ends a specific function. In voice signalling 'dog everything' stands alone and has no matching terminate command.

   Source: OSHA 29 CFR 1926 Subpart CC, Appendix A (Standard Method hand signals); CCO Signalperson Reference Manual, acceptable voice signal terminologyReport a problem with this question

9. 9. When voice signals are used to direct a mobile crane, each series of voice signals must contain three elements. In what order must they be given?

   • A.Function stop, then function and direction, then distance and/or speed
   • B.Function and direction, then distance and/or speed, then function stop✓ Answer
   • C.The signal person's name, then the crane identification, then the function
   • D.Distance and/or speed, then function and direction, then function stop

   Both the federal rule and the industry standard fix the order as function and direction, distance and/or speed, then function stop, so the operator always learns what will move and which way before hearing how far, and every motion ends with an explicit stop command. The stop is worded function-first — 'hoist stop' is correct and 'stop hoist' is not — and no extra words may be added to it.

   Source: OSHA 29 CFR 1926.1421, Signals — voice signals; ASME B30.5, Mobile and Locomotive Cranes, standard voice signalsReport a problem with this question

10. 10. A signal person is talking a load down onto a landing the operator cannot see. Which statement reflects correct voice-signal practice?

    • A.The distance called is the distance REMAINING to the target, and the word for slow speed is added at the END of the command✓ Answer
    • B.Distance is dropped once the load is out of sight, and only the stop command is used
    • C.The distance called is the distance the load has already travelled, and the word for slow speed is said first
    • D.The microphone is unkeyed between calls while the load is moving so the operator can reply

    Calling the distance remaining is what lets the operator meter the motion smoothly down to zero; calling distance travelled gives the operator no idea how much room is left. The slow-speed word always comes at the end so the function and direction are heard first, and the signal person keeps communication constant while the load is moving rather than unkeying mid-motion, painting a picture for an operator working blind.

    Source: CCO Signalperson Reference Manual, acceptable voice signal terminology; ASME B30.5, Mobile and Locomotive Cranes, standard voice signalsReport a problem with this question

11. 11. A signal person is standing on the ground facing the crane cab. She calls 'swing right.' Which way must the operator swing?

    • A.To the operator's right, because all directions are given from the operator's direction perspective✓ Answer
    • B.Neither — 'right' is undefined and the lift must be abandoned
    • C.To the signal person's right, which is the operator's left
    • D.Whichever direction shortens the load radius

    The federal rule and the industry standard both require every direction given to the operator to be stated from the OPERATOR's direction perspective, so 'swing right' always means the operator's right no matter where the signal person stands or which way she faces. Fixing the reference frame to the cab is what eliminates the mirror-image error when the signal person works face-to-face with the machine.

    Source: OSHA 29 CFR 1926.1419, Signals — general requirements; ASME B30.5, Mobile and Locomotive Cranes, standard voice signalsReport a problem with this question

12. 12. Radios will be used to pass signals to a mobile crane. Which set of requirements applies to that electronic transmission?

    • A.The operator may hold the radio in one hand as long as the crane is not travelling
    • B.Once radios are in use the operator need only obey the designated signal person
    • C.The devices are tested on site before operations begin, transmission is on a dedicated channel, and the operator's reception is hands-free✓ Answer
    • D.Any open channel may be used, provided the radios were function-tested back at the shop

    The federal rule requires the transmitting devices to be tested on site before operations so the transmission is confirmed effective, clear and reliable; requires a dedicated channel — with narrow exceptions letting multiple cranes and signal persons share one dedicated channel to coordinate, and for work coordinated with railroad operations; and requires the operator's reception to be hands-free so both hands stay on the controls. Radios never displace the duty to obey a stop signal from anyone.

    Source: OSHA 29 CFR 1926.1420, Signals — radio, telephone or other electronic transmission of signalsReport a problem with this question

13. 13. Mid-swing with a load on the hook, the operator's radio goes silent and the signal person is not in view. What must the operator do?

    • A.Continue the swing at reduced speed to the intended landing point
    • B.Bring the crane safely to a stop and keep it stopped until communication is reestablished and a proper signal is given and understood✓ Answer
    • C.Treat signal authority as passing automatically to the nearest rigger and keep going
    • D.Finish the swing, set the load down wherever it ends up, and continue when convenient

    Communication must be maintained continuously during all crane movements, and if the ability to transmit signals is interrupted at any time the operator stops operations that require signals and does not resume until communication is restored AND a proper signal has been given and understood. The stop itself must be made smoothly, because abruptly checking a swinging load lets its momentum carry the load out and add side load to the boom.

    Source: OSHA 29 CFR 1926.1419, Signals — general requirements; ASME B30.5, Mobile and Locomotive Cranes, signals sectionReport a problem with this question

14. 14. Audible signals are being used while a mobile crane is moved on site. Under the mobile crane standard, what do one, two and three short blasts mean?

    • A.One means stop, two means go ahead, three means back up✓ Answer
    • B.One means go ahead, two means stop, three means emergency stop
    • C.One means go ahead, two means back up, three means stop
    • D.One means back up, two means stop, three means go ahead

    The mobile crane standard sets the audible travel signals as one short signal for stop, two for go ahead and three for back up; the count is frequently mis-memorised as one meaning go. An emergency audible signal is treated separately: anyone may give it, it must be agreed on for the particular job site, and it is typically multiple short blasts or one continuous blast so it cannot be confused with the travel signals.

    Source: ASME B30.5, Mobile and Locomotive Cranes, audible travel signals and audible emergency signalReport a problem with this question

15. 15. Under the federal construction crane rule, when is a signal person required for mobile crane work?

    • A.Only when more than one crane is operating on the same site
    • B.Only when the crane is working within reach of energized power lines
    • C.Only when the load exceeds a set percentage of the crane's chart capacity
    • D.When the point of operation is not in full view of the operator, when the view in the direction of travel is obstructed, or when site-specific safety concerns lead the operator or the person handling the load to decide one is needed✓ Answer

    The rule lists three independent triggers: the point of operation — the load travel path or the area at or near load placement — not in full view of the operator; an obstructed view in the direction of travel while the equipment is travelling; and site-specific safety concerns that cause either the operator or the person handling the load to determine a signal person is necessary. The requirement turns on visibility and judgment, not on load weight or the number of machines on site.

    Source: OSHA 29 CFR 1926.1419, Signals — general requirementsReport a problem with this question

16. 16. Two workers begin calling directions to the same crane at once, and a third worker who is not the signal person sees a rigging problem and gives a stop signal. What is correct?

    • A.The operator must obey whichever signal came first and finish the movement in progress
    • B.All three may signal, since more voices on a lift improve safety
    • C.The operator may ignore the third worker, because only the designated signal person may stop the crane
    • D.Only one person may signal the crane at a time, but anyone who becomes aware of a safety problem may give a stop or emergency stop signal, and the operator must obey it✓ Answer

    Only one person may give signals to a crane at any one time — that is what keeps direction unambiguous, so the two competing signal-givers must be resolved down to one designated signal person. The single exception written into the rule is that anyone who becomes aware of a safety problem may give a stop or emergency stop signal, and the operating requirements make obeying a stop or emergency stop signal mandatory regardless of who gives it.

    Source: OSHA 29 CFR 1926.1419, Signals — general requirements; OSHA 29 CFR 1926.1417, OperationReport a problem with this question

17. 17. During a lift the operator glimpses a hand signal only partially and cannot tell whether it was lower or stop. What must the operator do?

    • A.Assume the signal person will repeat it and hold the load in place while continuing to swing
    • B.Make no response to the unclear signal — stop crane movement until the signal is clarified and clearly understood✓ Answer
    • C.Keep the previous function running until a clearer signal arrives
    • D.Choose the more conservative of the two readings and lower the load slowly

    The standard requires signals to be discernible or audible at all times and states plainly that no response shall be made unless the signal is clearly understood, so a partly seen or ambiguous signal is never to be best-guessed. If the operator has any concern about the requested movement, all crane movement stops and does not resume until the operator and the signal person agree the issue is resolved; sounding one blast of the horn is the customary way to get the signal person's attention.

    Source: ASME B30.5, Mobile and Locomotive Cranes, signals section; OSHA 29 CFR 1926.1419, Signals — general requirementsReport a problem with this question

18. 18. A signal person leaves one employer and is hired by another. Which qualification, if any, carries over to the new employer?

    • A.Documentation from a third-party qualified evaluator carries over; an assessment done by the previous employer's own qualified evaluator does not✓ Answer
    • B.Only a hand-signal qualification carries over; qualification for radio signalling never transfers
    • C.Both carry over, because the qualification attaches to the person rather than the employer
    • D.Neither carries over; every employer must requalify every signal person from scratch

    The federal rule gives the employer two routes to qualify a signal person — documentation from a third-party qualified evaluator, or an assessment by the employer's own qualified evaluator — and only the third-party documentation is portable between employers, because the second route documents an assessment that employer made for its own use. Either way the employer must ensure the person is qualified before they give any signals, the documentation must be available at the site, and it must state each type of signalling the person is qualified for.

    Source: OSHA 29 CFR 1926.1428, Signal person qualificationsReport a problem with this question

19. 19. On a long travel-and-place operation the load will pass out of the first signal person's view and a second signal person will take over, and the same signal person is also serving a second crane nearby. Which practice is required?

    • A.Only one signal person directs the crane at any moment, the handoff is explicit and acknowledged by the operator, and when one signal person serves more than one crane the crane must be identified before the function and direction are given✓ Answer
    • B.The operator chooses whichever signal person happens to have the better view at each moment
    • C.The second signal person simply takes over silently the instant the first loses sight of the load
    • D.Both signal persons may signal at the same time as long as they agreed on the plan beforehand

    Because only one person may direct the crane at a time, a handoff has to be explicit: the incoming signal person and the operator contact and identify each other by name and the operator acknowledges before movement continues, so there is never a moment when nobody or two people are in charge. Separately, where one signal person is signalling more than one crane, the rule requires the crane to be identified before the function and direction are given, or by an equally effective method, so an instruction meant for one machine is not acted on by the other.

    Source: OSHA 29 CFR 1926.1419, Signals — general requirementsReport a problem with this question

20. 20. The signal person calls for a swing that would carry the suspended load directly over two workers who are not part of the lift. What is the operator's authority and duty?

    • A.Make the swing at reduced speed so the workers have time to move clear
    • B.Follow the signal, because the signal person directs the lift and carries the responsibility for it
    • C.Follow the signal but sound the horn continuously as a warning to the workers below
    • D.Stop the operation and keep it stopped until the hazard is corrected — the operator has the authority to refuse a movement they judge unsafe✓ Answer

    The operator retains both the authority and the duty to stop and refuse any operation they believe to be unsafe, and once stopped, movement does not resume until the operator and the signal person agree the concern has been resolved. Personnel must be kept out of the fall zone and out from under a suspended load; a horn blast or a slower swing does not make carrying a load over people acceptable, since a dropped load or a shifting rigging failure gives them no time to react.

    Source: ASME B30.5, Mobile and Locomotive Cranes, signals section; OSHA 29 CFR 1926.1419, Signals — general requirementsReport 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 →