Mechanical engineers are licensed through the PE system. This overview covers the FE Mechanical and the three NCEES PE Mechanical depth exams — Machine Design & Materials, Thermal & Fluids Systems, and HVAC & Refrigeration — and how to choose between them.
The path is FE Mechanical → ~4 years of qualifying experience → a PE Mechanical depth exam → state-board licensure. NCEES offers three depth areas; you pick the one that matches your practice. All are computer-based and offered year-round.
Fundamentals of Engineering — the first step toward the Mechanical PE.
PE depth for machine design, materials and mechanical systems.
150 original questions going deeper than the free exam above — trickier multi-step stress and fatigue calculations, subtler failure-theory distinctions, and more application-level design scenarios. Instant online access after purchase, good for 90 days — take it as many times as you want.
Or skip picking — the All-Access Pass unlocks every Professional Program, exam, and premium guide on the site, including anything added later, for one flat price.
PE depth for thermodynamics, fluids, heat transfer and energy systems.
150 original questions going deeper than the free exam above — trickier multi-step thermodynamic-cycle and fluid-flow calculations, subtler distinctions between cycle analyses, and more application-level scenarios. Instant online access after purchase, good for 90 days — take it as many times as you want.
Or skip picking — the All-Access Pass unlocks every Professional Program, exam, and premium guide on the site, including anything added later, for one flat price.
PE depth for HVAC and refrigeration system design.
150 original questions going deeper than the free exam above — trickier multi-step load and psychrometric calculations, subtler code/standard application scenarios, and more real-world system-design questions. Instant online access after purchase, good for 90 days — take it as many times as you want.
Or skip picking — the All-Access Pass unlocks every Professional Program, exam, and premium guide on the site, including anything added later, for one flat price.
| Credential | Prerequisite | Typical experience | Administered by |
|---|---|---|---|
| FE Mechanical | Mechanical coursework | Final-year student / grad | NCEES |
| PE Mechanical: Machine Design | Pass FE | ~4 years under a PE* | NCEES + state board |
| PE Mechanical: Thermal & Fluids | Pass FE | ~4 years under a PE* | NCEES + state board |
| PE Mechanical: HVAC & Refrigeration | Pass FE | ~4 years under a PE* | NCEES + state board |
* Experience hours and prerequisites vary significantly by state, jurisdiction and credential level. Figures shown are typical ranges, not legal requirements.
The three PE Mechanical depths share little. Pick the one you actually practice — Machine Design, Thermal & Fluids, or HVAC & Refrigeration — and go deep on its references.
Stress/fatigue, thermodynamic cycles, fluid/piping and heat-transfer problems recur. Build speed with timed sets — and rehearse with the studio’s pipe, pump and heat-exchanger tools.
Use the same edition of the code/handbook the exam is written to, and the certifying body’s official references. Exams are tied to a specific cycle — the wrong edition costs you on lookup questions.
Confirm the exact education, experience hours and application steps with the certifying body or state board first — missing a prerequisite trips up more people than the exam content does.
Many exam questions are calculation problems you can rehearse right now with the free tools in the Mechanical Systems Studio: