- How the CET Exam Domains Break Down
- Domain 1: Maintenance (15%)
- Domain 2: Electric Traction (14%)
- Domain 3: Safety (13%)
- Domain 4: Hydraulic (12%)
- Domain 5: Controls (12%)
- Domain 6: Hoistway (10%)
- Domain 7: Car Enclosure (6%)
- Domain 8: Escalators (5%)
- Domain 9: Special Applications (5%)
- Domain 10: Job Site (4%)
- Domain 11: Lifts (4%)
- Scheduling Your Prep Around the Domains
- FAQ
- Maintenance is the largest domain at 15% (24 of 160 questions), so it deserves the most study hours.
- The top five domains - Maintenance, Electric Traction, Safety, Hydraulic, Controls - cover roughly two-thirds of the 160-question exam.
- All 11 domains draw from the Safety Handbook, Elevator Maintenance Manual, NEMI Installation Manual, and ASME A17.1/A17.3.
- The exam is computer-based, 160 multiple-choice items, scored 300-500 with 300 needed to pass.
How the CET Exam Domains Break Down
The Certified Elevator Technician (CET) exam, administered by the National Association of Elevator Contractors (NAEC) through the NAEC Certification Board, is a 160-question computer-based multiple-choice test delivered online under proctored conditions after you receive your Authorization to Test letter. Every one of those 160 questions falls into one of 11 content domains, and NAEC weights them unevenly - meaning some topics simply matter more to your score than others.
Understanding this weighting isn't just academic. It tells you exactly where to spend your limited study time. If you're still building your overall prep plan, pair this breakdown with our CET Study Guide 2026: How to Pass on Your First Attempt for a full walkthrough of the process from application to test day.
| Domain | Weight | Approx. Questions (of 160) |
|---|---|---|
| Maintenance | 15% | 24 |
| Electric Traction | 14% | 23 |
| Safety | 13% | 20 |
| Hydraulic | 12% | 20 |
| Controls | 12% | 19 |
| Hoistway | 10% | 16 |
| Car Enclosure | 6% | 10 |
| Escalators | 5% | 8 |
| Special Applications | 5% | 8 |
| Job Site | 4% | 6 |
| Lifts | 4% | 6 |
For a deeper look at how this weighting translates into a passing strategy, see CET Passing Score 2026: Exactly What You Need to Pass, which explains the 300-500 scoring scale in detail.
Domain 1: Maintenance (15%)
Maintenance
As the single largest domain, Maintenance covers the routine inspection, lubrication, adjustment, and troubleshooting tasks that keep elevator systems running safely between major repairs. Expect questions tied directly to the Elevator Maintenance Manual referenced in NAEC's certification requirements.
- Preventive maintenance schedules and lubrication intervals
- Diagnosing wear on ropes, guides, and mechanical linkages
- Interpreting maintenance logs and manufacturer-specified tolerances
- Adjustment procedures for doors, leveling, and ride quality
Because this domain alone represents 24 questions, weak recall here has an outsized effect on your overall score. Candidates coming through the on-the-job hours pathway often have strong field intuition but should still cross-check their habits against manual-specified procedures, since the exam tests documented standards, not shop-floor shortcuts.
Domain 2: Electric Traction (14%)
Electric Traction
Electric Traction is the second-heaviest domain and focuses on traction elevator systems: machines, motors, ropes, sheaves, and the electrical components that drive car movement.
- Traction machine components and gearing configurations
- Rope and sheave inspection criteria
- Motor and drive fundamentals for traction systems
- Governor and overspeed protection basics
This domain and Maintenance together account for close to a third of the entire exam, so a candidate who masters both has already secured a substantial share of the 300-point passing threshold.
Domain 3: Safety (13%)
Safety
Safety is weighted heavily and draws directly from the Elevator Industry Field Employees' Safety Handbook that every applicant must demonstrate knowledge of before sitting the exam.
- Lockout/tagout and hoistway access procedures
- Personal protective equipment requirements on job sites
- Fall protection and confined-space awareness
- Emergency response and rescue protocols
Key Takeaway
Because Safety questions are pulled from a single named handbook, this is one of the most efficient domains to study - read the handbook directly rather than relying only on secondary study material.
Domain 4: Hydraulic (12%)
Hydraulic
Hydraulic systems differ substantially from traction systems in how they generate motion, and this domain tests that distinct body of knowledge.
- Pump units, valves, and jack configurations
- Hydraulic fluid specifications and contamination checks
- Pressure relief and overload protection systems
- Common hydraulic-specific failure modes
Candidates whose field experience leans heavily toward traction work sometimes underestimate Hydraulic, but at 20 of 160 questions it ties Safety for the fourth-largest share of the exam.
Domain 5: Controls (12%)
Controls
Controls covers the logic and electrical systems that govern car dispatch, floor selection, and system diagnostics.
- Relay logic versus microprocessor-based control systems
- Wiring diagram interpretation
- Fault-code diagnostics and troubleshooting sequences
- Dispatch and group control fundamentals
Controls rounds out the top five domains at 19 questions. Together, Maintenance, Electric Traction, Safety, Hydraulic, and Controls make up the backbone of the exam, and mastering the code references behind them - ASME A17.1 and A17.3 - pays dividends across multiple domains at once.
Domain 6: Hoistway (10%)
Hoistway
Hoistway questions address the structural and mechanical environment surrounding the elevator car itself.
- Guide rail alignment and bracket spacing
- Pit and overhead clearance requirements
- Hoistway door interlocks and gate switches
- Buffer and counterweight systems
Domain 7: Car Enclosure (6%)
Car Enclosure
This domain narrows in on the cab itself - the components riders interact with directly.
- Car door operators and safety edges
- Cab fixtures, signals, and emergency communication
- Ventilation and lighting code requirements
Domain 8: Escalators (5%)
Escalators
Escalators shift focus away from vertical transportation to inclined moving-stair systems.
- Step, chain, and comb plate maintenance
- Skirt panel and safety switch inspection
- Handrail drive and speed synchronization
Domain 9: Special Applications (5%)
Special Applications
This domain covers non-standard installations that fall outside conventional passenger elevators.
- Freight and service elevator distinctions
- Specialized code provisions for unique installations
- Equipment adaptations for atypical building configurations
Domain 10: Job Site (4%)
Job Site
Job Site questions test practical field awareness beyond pure mechanical knowledge.
- Coordination with general contractors and inspectors
- Job site documentation and reporting practices
- Material handling and storage on active construction sites
Domain 11: Lifts (4%)
Lifts
The smallest domain by weight, Lifts covers wheelchair lifts, dumbwaiters, and similar limited-use equipment.
- Platform and inclined lift safety features
- Limited-use/limited-application equipment distinctions
- Code differences between lifts and full passenger elevators
Scheduling Your Prep Around the Domains
Once you know the weighting, the smartest approach is to allocate study time proportionally rather than evenly across all 11 domains. A candidate qualifying through the education pathway - NAEC's Education Program, NEIEP, or L.I.T.S. - will already have structured exposure to most topics, while those qualifying through the 10,000-hour/five-year on-the-job pathway may need to fill in domains their specific field assignments didn't cover.
Maintenance and Electric Traction
- Review Elevator Maintenance Manual procedures
- Study traction machine components and rope inspection criteria
Safety, Hydraulic, and Controls
- Read the Safety Handbook cover to cover
- Compare hydraulic and control system diagrams side by side
Hoistway, Car Enclosure, and Code References
- Cross-reference ASME A17.1 and A17.3 sections tied to each domain
- Drill hoistway clearance and interlock questions
Escalators, Special Applications, Job Site, Lifts
- Cover the four smallest domains together in one focused block
- Take full-length practice sets to simulate the 160-question format
If you want a condensed reference to revisit in the final days before your test, our CET Cheat Sheet 2026: One-Page Review of Must-Know Facts distills the highest-yield facts across all 11 domains. And if you're still deciding whether the exam matches your current skill level, How Hard Is the CET Exam? Complete Difficulty Guide 2026 breaks down the format and difficulty in more depth.
Key Takeaway
Weight your study hours to match domain weight - Maintenance and Electric Traction combined deserve nearly twice the attention of Hoistway and Car Enclosure combined.
Practicing under realistic conditions matters as much as content review. Running full-length, timed practice exams on our practice test platform helps you get comfortable with the 160-question, multiple-choice format before your proctored session begins. Repeated exposure through domain-specific practice questions is one of the most direct ways to confirm you're ready across all 11 areas, not just the ones you find most interesting.
It's also worth remembering that domain mastery ties directly into registration mechanics. Application fees run $680 for employees of NAEC member companies or $1,095 for non-members under the experience pathway, and $95 or $145 respectively under the education pathway - costs that make it worthwhile to prepare thoroughly rather than risk a retest. For the full fee schedule and retest timing, see CET Certification Cost 2026: Complete Pricing Breakdown. And if you're unsure whether you currently qualify to apply at all, review CET Requirements 2026: Eligibility, Prerequisites & How to Qualify before mapping out a domain study schedule.
Frequently Asked Questions
Maintenance is the largest domain, accounting for 24 of the 160 total questions (15% of the exam), followed closely by Electric Traction at 23 questions.
Yes, in large part. NAEC requires candidates to know the Elevator Industry Field Employees' Safety Handbook, the Elevator Maintenance Manual, the NEMI Installation Manual, and ASME A17.1 and A17.3, and these sources feed into multiple domains rather than just one.
Yes. While Lifts and Job Site each represent only 4% of the exam, the four smallest domains combined make up close to a fifth of all 160 questions, which is too significant to ignore.
The overall exam is scored on a 100 to 500 scale with 300 required to pass. Candidates who don't pass receive a category-level diagnostic report showing correct answers per domain, which helps target retest preparation.
You can retest after a 30-day wait for the second attempt, and after a further 30 days plus a $100 fee for a third attempt; after a third failure, reapplication requires a 180-day wait. Use the diagnostic report to focus your review on the exact domains where you fell short.