NCEES PE Mechanical · the exam
The PE Mechanical exam
PE Mechanical is three separate depth exams — you sit one to get licensed. This page is the whole picture: what it is, the format all three share, which depth to pick, and how to get ready.
An email address is all it takes.
Choose your depth
You sit one depth. Pick the one that matches your day-to-day engineering work, where your experience does the most for you.
HVAC & Refrigeration
- Who it's for
- Building-mechanical, HVAC, refrigeration
- Pass rate
- ~69–71% first-time — the most-taken depth
- Heavy on
- Equipment & systems; psychrometrics is where it's won or lost
Machine Design & Materials
- Who it's for
- Machine/product design, components, manufacturing, materials
- Pass rate
- ~61–64% first-time — the broadest, most demanding
- Heavy on
- The mechanics-of-materials spine; fatigue
Thermal & Fluid Systems
- Who it's for
- Power, energy, process, fluid systems
- Pass rate
- ~70–71% first-time — the highest, and fastest-growing
- Heavy on
- Power cycles; compressible flow
Still deciding? See which depth to take (the full breakdown — roles, industries, edge cases) and pass rates.
The format every depth shares
- 80 questions over a nine-hour appointment — about 8 hours of testing, plus the tutorial and one optional scheduled break.
- Computer-based and offered year-round at Pearson VUE.
- Closed book — your only reference is the on-screen NCEES PE Mechanical Reference Handbook, so navigating it fast is its own exam skill.
- Standard multiple choice plus alternative item types (drag-and-drop, point-and-click, multiple-correct, fill-in).
- Scored against a scaled cut score — NCEES publishes no fixed passing percentage. At ~6 minutes a question, pacing matters.
- Units vary by depth: HVAC & Refrigeration is U.S. customary; Machine Design & Materials and Thermal & Fluid Systems use both SI and U.S. customary.
More: What to expect on exam day · Registration · Approved calculators · Using the Reference Handbook.
How candidates get ready
- 1
Pick the depth that matches your work.
- 2
Diagnose first — find your weak areas before you study, not after.
- 3
Go problems-first — drill exam-real problems, not chapters; let your misses set the plan.
- 4
Rehearse closed-book Handbook navigation until finding equations and tables is automatic.
- 5
Finish with timed, full-length mocks to lock in your eight-hour pace.
Plan on ~200–300 hours over about four months, weighted to your weak and heavy areas. How to pass the PE Mechanical exam — the full plan →
How CastorPrep helps
Practice
Exam-real problems
Tagged to the NCEES spec, so practice matches the real weighting.
Tutor
Grounded AI tutor
Answers your questions and walks the method — on every problem, citing the Handbook section where the problem carries one.
Mocks
Full-length mocks
Timed, to rehearse your eight-hour pace.
Diagnose
The diagnostic
Maps your weak areas and ranks what to drill first.
An email address is all it takes.
Exam FAQ
How is the PE Mechanical exam structured?
Three separate depth exams — HVAC & Refrigeration, Machine Design & Materials, Thermal & Fluid Systems — and you sit one. Each is 80 questions over a nine-hour appointment (~8 hours of testing), closed book with the on-screen NCEES Reference Handbook, computer-based and offered year-round.
Which depth should I take?
The one that matches your engineering work — you only have to pass one. Compare the three below, or see the full pass-rate breakdown and the depth chooser.
What units does the exam use?
It depends on the depth: HVAC & Refrigeration is U.S. customary (USCS); Machine Design & Materials and Thermal & Fluid Systems use both SI and U.S. customary.
Open book or closed book?
Closed book. Your only reference is the on-screen NCEES PE Mechanical Reference Handbook, so knowing where things live in it is its own exam skill.
What score do I need to pass?
NCEES uses a scaled cut score and doesn't publish a fixed passing percentage. The goal is mastery of the tested areas, not a magic number.
How long should I study?
Most candidates need ~200–300 hours over about four months, weighted to weak and heavy areas.
What if it takes more than one attempt?
It's offered year-round, within NCEES/state-board attempt limits. A retake plan that changes the method — not just the hours — is what moves the score.
Pick your depth and see whether it clicks before you pay a cent.
An email address is all it takes.