NCCCO Core written exam: format and domains

The Core exam is the written exam every mobile crane operator candidate takes, whatever the crane type. This page sets out the exam facts, with three sample questions and a free check; for a longer free set, use the NCCCO practice test.

What the domains mean in practice

Each specialty exam has its own outline. Load charts are about 35% of each one, and a calculator is allowed; the specialty written exams comparison sets LAT, TLL, TSS and STC side by side. For a way to organize your Core preparation, see the NCCCO Core study guide, and for what a paid NCCCO exam prep course should include, read our comparison. The crane terms glossary explains twenty crane and rigging terms from these domains, each with a drawing.

Signalperson and Rigger certifications have their own written exams; see how NCCCO rigger certification and Signalperson work.

Lift Director for Mobile Cranes includes the Core written exam too, and certified CCO operators skip it; see NCCCO Lift Director certification.

Want more questions? The free NCCCO practice test has three more explained samples.

The 12-month window and retakes

Passing your first exam starts the clock. The handbook gives you 12 months from that pass to pass the other exams for the same crane designation: Core, the written specialty and the matching practical. If you fail a written exam, NCCCO's retake policy has you wait four weeks before you sit that same exam again, unless an alternate form is available. Build that wait into your dates so a retake still lands inside the window. The NCCCO written test cost and retakes guide has the fees and the full retake rule.

How to prepare

• Take the free check and look at your load chart and technical knowledge scores first.
• Practice chart problems end to end on practice charts: configuration, radius, gross capacity, deductions, net capacity.
• Do the arithmetic by hand, since the Core exam has no calculator.
• Use spare minutes on the free NCCCO written flashcards: grade each card and the ones you miss come back sooner.
• Plan the logistics too: NCCCO written exam day: what to bring covers pacing and results, and test center versus online testing and testing locations shows where to book.
• For the signals part of Operations, run the crane hand signals drill until you can name every standard signal on sight.
• Plan your exams inside the 12-month window, and remember the four-week wait before retaking a written exam.
• In the final week before your test date, follow the last-7-days Core study plan to fix your biggest leaks and practice your pacing.

3 sample Core questions with answers

These are original practice questions written to the Core outline, not exam items. Cover the answer, pick one, then read why.

1. Technical knowledge

During your shift inspection you find a kinked section on the hoist rope. What do you do?

• A. Lubricate the section and keep working
• B. Lift only light loads until the end of the shift
• C. Keep the load close to the ground and watch the kink
• D. Do not lift, report it, and keep the crane out of service until the rope is replaced

Answer: D. A kink is damage that does not heal, and it is a removal-from-service condition, so the inspection ends the lift before it starts. Lubricating (A) hides nothing and fixes nothing. Light loads (B) and staying low (C) still put a damaged rope on the hook. See OSHA 1926.1413 on wire rope inspection.

2. Operations

Before you assemble the boom, you notice an energized power line near the work area. What comes first?

• A. Work slowly and watch the boom tip
• B. Decide whether any part of the crane or load could come within 20 feet of the line, and follow the power line rules if it could
• C. Ask the crew to stay away from the line
• D. Assume the line is dead if it has no insulation

Answer: B. The check comes before assembly, and it covers the crane, the load and the boom's whole reach, not only the tip. Working slowly (A) and warning the crew (C) are not clearance. A bare line (D) is the most dangerous kind to assume dead. See OSHA 1926.1407. To see how the clearance distance changes with line voltage, try the crane power line clearance calculator.

3. Load charts

The boom is 60 ft long at a 60 degree angle. Ignoring the boom-foot offset and deflection, what is the load radius?

• A. 52 ft
• B. 30 ft
• C. 60 ft
• D. 120 ft

Answer: B. Radius is the horizontal run, so it is boom length times the cosine of the angle: 60 × 0.5 = 30 ft. Option A uses the sine, which gives the height of the boom tip, not the radius. Option C is the boom length itself, which would only be the radius at 0 degrees. Do this by hand: the Core exam has no calculator. Check your own numbers with the crane radius and boom angle calculator.

Take the free 10-question check

Take the free 10-question check and see your score by Core domain in minutes, with no signup. The course adds full timed exams that match the Core format, explained answers on every question, and a plan built from your weakest domain.

FAQ

How many questions are on the NCCCO Core exam?

95. The handbook splits them across four domains: Site 22%, Operations 28%, Technical Knowledge 23% and Load Charts 27%. Older practice sets that quote 90 questions were built on the January 2024 handbook, not the current outline.

How long is the NCCCO Core exam?

90 minutes for the 95 questions, which works out to just under a minute a question (our arithmetic). Chart problems take longer than recall questions, so bank time on the quick ones.

Can you use a calculator on the NCCCO Core exam?

No. The handbook marks the Core exam calculator not permitted, so radius, deductions and net capacity are done by hand. The written specialty exams are different: 28 questions in 60 minutes, with a calculator permitted.

What score do you need to pass the NCCCO Core exam?

The current candidate handbook does not print a numeric written passing score. The scoring and testing locations guide explains what older handbooks said and why a practice percentage is not a passing score.

How should I prepare for the NCCCO Core exam?

Start with the free 10-question check to find your weakest domain. Then work load charts end to end by hand, since they carry 27% of the exam, and use the NCCCO Core study guide to plan the rest.

Where do our practice questions come from?

Every question is original and written to NCCCO's published Core outline.

Sources

Show the list

• Mobile Crane Operator Candidate Handbook, CCO, cover revision 01/25. Core format, calculator rule and domain weights on printed page 2; specialty format on printed page 4; eligibility and the 12-month window on printed page 1. Checked 7 Nov 2026.
• Exam Retake Policy: Frequently Asked Questions, NCCCO. Four-week written retake wait. Retrieved 17 Oct 2026.