- What the CPFT/RPFT Exam Actually Looks Like
- 115 Questions, Two Different Outcomes
- The Three Domains and Why the Split Matters
- Inside Each Domain: What You Must Know
- Registration, Fees, and Testing Mechanics
- How Scoring Works: Two Cut Scores, One Exam
- Mapping Domains to a Prep Schedule
- Keeping the Credential Active
- Frequently Asked Questions
- The exam has 115 total questions (100 scored, 15 unscored pretest) and a strict 2-hour time limit.
- One sitting produces two possible outcomes: a low-cut CPFT pass or a high-cut RPFT pass.
- Procedures is the largest domain at 44%, making it the single highest-leverage area to master.
- New applicants pay $200; repeat applicants pay $170 - fees go to the NBRC at PSI testing centers or approved remote proctoring.
What the CPFT/RPFT Exam Actually Looks Like
The Pulmonary Function Technology Examination is administered by the National Board for Respiratory Care (NBRC) through PSI assessment centers and eligible remote proctoring locations. If you have been preparing for this exam, you already know that pulmonary function testing is a technically demanding specialty - and the exam reflects that. Every question is multiple-choice, computer-delivered, and drawn from the PFT Detailed Content Outline effective October 2022.
What makes this exam unusual is that it produces two distinct credential outcomes from a single sitting. Depending on where your score lands relative to two separate cut scores, you may earn the Certified Pulmonary Function Technologist (CPFT) credential, the Registered Pulmonary Function Technologist (RPFT) credential, or neither. That single-exam, dual-outcome structure shapes how every serious candidate should approach their preparation - because the goal is not just to pass, but to understand clearly which credential you are aiming for and what score threshold you need to clear.
Before diving into domains and scoring, make sure you have confirmed your eligibility pathway. The NBRC recognizes four distinct routes into this exam, and your eligibility determines which credential outcomes are even available to you. Review the full breakdown at CPFT/RPFT Eligibility Requirements: All 4 Routes Explained if you have any uncertainty about your qualifications before registering.
115 Questions, Two Different Outcomes
The exam presents 115 questions, but not all of them count toward your score. 100 questions are scored; the remaining 15 are pretest (unscored) questions that the NBRC uses to evaluate new items for future exams. You will have no way to identify which questions are pretest items during your exam, which means you must treat every single question as if it counts. Skipping or rushing through questions because you assume they might be unscored is a strategy that will hurt you.
Two hours is less time than many candidates expect. At 115 questions in 120 minutes, you have roughly one minute and three seconds per question on average. For straightforward recall questions - equipment specifications, normal reference ranges, ATS/ERS acceptability criteria - that is comfortable. For complex clinical scenario questions that require you to interpret multiple data points, it is tight. Candidates who have not practiced under timed conditions often find themselves scrambling in the final 20 minutes.
Using a CPFT/RPFT practice test platform that replicates the exact 100-question scored format and enforces the time limit is one of the most direct ways to calibrate your pacing before exam day.
Question Format Details
Every question on the PFT exam is a four-option multiple-choice item. There are no true/false, drag-and-drop, or fill-in-the-blank questions.
- All questions are computer-delivered at PSI testing locations
- 15 of 115 questions are unscored pretest items - you cannot identify them
- You must answer all 115; there is no mechanism to flag and skip permanently
- Questions span all three content domains in proportions set by the content outline
The Three Domains and Why the Split Matters
The PFT exam content outline organizes all 100 scored questions across three domains. Understanding the weight of each domain is not optional information - it is the foundation of any rational study plan.
| Domain | Topic Area | Weight | Approx. Scored Questions |
|---|---|---|---|
| Domain 1 | Instrumentation / Equipment | 33% | ~33 questions |
| Domain 2 | Procedures | 44% | ~44 questions |
| Domain 3 | Data Management | 23% | ~23 questions |
Domain 2 - Procedures - accounts for nearly half of your scored exam. That alone tells you where concentrated preparation time pays the highest return. Domain 1 at 33% is a close second in weight and covers highly technical equipment content that many candidates underestimate. Domain 3 at 23% is the smallest domain but covers interpretation and reporting, which overlaps significantly with the clinical reasoning required to reach an RPFT-level cut score.
Inside Each Domain: What You Must Know
Domain 1: Instrumentation / Equipment (33%)
Instrumentation / Equipment
This domain tests your understanding of the physical equipment used in pulmonary function testing - how it works, how it is calibrated, and how equipment failure manifests in test results.
- Spirometer types: volume-displacement vs. flow-sensing (pneumotachographs, turbines, ultrasonic)
- Body plethysmograph principles - panting frequency, cabinet leak, shutter timing
- DLCO analyzers: rapid single-breath systems, calibration gas requirements, leak testing
- ATS/ERS calibration standards: 3-liter syringe verification, linearity checks, temperature/BTPS corrections
- Infection control: spirometer cleaning, bacteriostatic filters, cross-contamination prevention
- Bronchial challenge delivery devices: dosimeter vs. continuous nebulization methods
Equipment questions often appear as clinical scenarios where a result looks abnormal - and the correct answer requires you to determine whether the abnormality is physiologic or equipment-related. Recognizing a leaking pneumotach, an improperly zeroed flow sensor, or a body box calibration drift is the type of applied knowledge this domain tests repeatedly.
Domain 2: Procedures (44%)
Procedures
The largest domain covers patient preparation, test performance, quality control during testing, and recognition of procedure errors. This is where clinical floor knowledge translates directly into exam points.
- Spirometry: ATS/ERS acceptability and repeatability criteria, effort-dependent vs. effort-independent maneuvers
- Lung volumes: plethysmography, nitrogen washout, helium dilution - technique differences and when to choose each
- DLCO: single-breath technique, breath-hold timing, washout volume, correcting for hemoglobin and altitude
- Bronchial provocation: methacholine and mannitol protocols, dose-response curves, safety endpoints
- Exercise testing: 6-minute walk test, incremental cycle ergometry, monitoring parameters
- Pediatric testing: coaching techniques, effort assessment, reference value selection
- Patient contraindications: when to withhold bronchodilators, absolute contraindications to maximum effort maneuvers
Because Procedures accounts for 44 of your roughly 100 scored questions, a weak performance here cannot be salvaged by excellent scores in the other two domains. Candidates aiming for the RPFT-level cut score must not only know correct technique but must be able to recognize and troubleshoot suboptimal efforts in clinical vignette-style questions.
Domain 3: Data Management (23%)
Data Management
Data Management covers interpretation, reporting, and communication of pulmonary function results within a clinical context.
- Interpreting spirometry patterns: obstructive, restrictive, mixed - using lower limit of normal (LLN) vs. fixed cutoffs
- Severity grading of ventilatory defects per current guidelines
- DLCO interpretation: isolated reduction, combined with ventilatory pattern, corrected vs. uncorrected values
- Bronchodilator response criteria: percent change and absolute change thresholds
- Reference value selection: choosing appropriate predicted equations for patient demographics
- Quality grading of test sessions: assigning ATS/ERS grades A through F
- Reporting: communicating technical quality issues to ordering physicians
Registration, Fees, and Testing Mechanics
Registration is handled through the NBRC. Once your application is approved, you schedule your testing appointment through PSI, which operates both physical assessment centers and an approved remote proctoring platform. Remote proctoring eligibility is not automatic - check NBRC and PSI requirements for your specific situation before selecting that option.
Fees are straightforward:
- New applicant: $200 USD
- Repeat applicant: $170 USD
The $30 reduction for repeat applicants reflects that a portion of the initial fee covers application processing. If you do not pass on your first attempt, you will need to reapply through the NBRC before scheduling a retake - you cannot simply rebook through PSI directly.
Eligibility to sit for the exam requires you to be at least 18 years old and to meet one of the NBRC's four recognized routes. These routes include completion of a CoARC-accredited respiratory therapy education program, holding CRT or RRT status, holding current CPFT status (as the prerequisite pathway for RPFT candidates), or completing 62 semester hours of college coursework including required sciences and mathematics combined with documented PFT clinical experience. For a complete breakdown of each route and what documentation you need, visit CPFT/RPFT Eligibility Requirements: All 4 Routes Explained.
How Scoring Works: Two Cut Scores, One Exam
The NBRC sets two distinct cut scores for the PFT examination: a low cut score and a high cut score. Your performance relative to these two thresholds determines which credential, if any, you earn.
- Score below the low cut: No credential awarded
- Score at or above the low cut, but below the high cut: CPFT credential awarded
- Score at or above the high cut: RPFT credential awarded
The NBRC does not publish specific numeric cut score values - they are determined through a standard-setting process and may be adjusted over time. What this means practically is that you cannot target a specific number of correct answers and guarantee an outcome. Your preparation strategy should be to maximize your demonstrated competency across all three domains, not to aim for a minimum passing score.
Candidates who have been working in PFT labs for years sometimes underperform on the RPFT cut because they have strong procedural knowledge but weaker equipment and data management fundamentals. A structured CPFT/RPFT practice test program that provides domain-by-domain performance feedback is particularly valuable for identifying these gaps before exam day.
Mapping Domains to a Prep Schedule
Given the domain weights, a rational approach assigns study intensity proportional to exam impact. Here is a four-week framework anchored to the actual content outline:
Domain 2: Procedures - Foundation (44%)
- Review ATS/ERS spirometry acceptability and repeatability criteria in full
- Master the three lung volume methods and their clinical indications
- Work through DLCO single-breath technique including timing, gas composition, and correction factors
- Take a baseline timed practice set focused on Procedures questions only
Domain 1: Instrumentation / Equipment (33%)
- Review all major spirometer types and their calibration requirements
- Study body plethysmograph mechanics and common error sources
- Cover DLCO analyzer calibration and infection control protocols
- Practice equipment troubleshooting scenarios - trace/waveform recognition
Domain 3: Data Management + Procedures (continued)
- Systematically work through spirometry interpretation patterns using LLN-based criteria
- Practice DLCO and lung volume result interpretation in combined clinical scenarios
- Return to bronchial provocation and exercise testing content from Domain 2
- Focus on bronchodilator response criteria and quality grading
Full Exam Simulation and Gap Closure
- Complete two or more full 100-question timed practice exams
- Review every incorrect answer and map it to a specific domain and sub-topic
- Spend remaining study days on the domain where your error rate is highest
- Simulate exam-day conditions: PSI-style interface, no notes, 2-hour limit
This schedule applies the principle of proportional effort: Domain 2 gets the most dedicated blocks, Domain 1 a full focused week, and Domain 3 is integrated with a second pass on Procedures in Week 3 - because data management questions frequently reference procedural context.
Keeping the Credential Active
Earning the CPFT or RPFT is not a one-time achievement. The NBRC administers credential maintenance through the NBRC Continuing Competency Program, with a renewal cycle of every 5 years. To maintain your credential, you must meet one of three pathways during each five-year cycle:
- Complete 30 continuing education (CE) hours in approved pulmonary function-related content
- Retest on the PFT examination
- Earn a new NBRC credential
In addition to the five-year requirement, credential holders must pay an annual fee to the NBRC to maintain active status. Allowing your credential to lapse has consequences beyond simply losing the letters after your name - as noted above, an inactive CPFT credential affects eligibility for the RPFT examination. Build the renewal cycle into your professional development calendar well before the deadline.
Employers in hospital-based pulmonary function labs, outpatient respiratory clinics, research institutions, and sleep/pulmonary specialty centers consistently require or strongly prefer credentialed PFT professionals. The CPFT is typically the entry-level marker for these roles, while the RPFT signals advanced clinical competency and is often associated with lead technologist or supervisory positions - though the NBRC does not publish salary data and individual employer requirements vary.
Key Takeaway
Start tracking CE hours from the day you earn your credential - not the year before renewal is due. Thirty hours over five years is manageable; thirty hours scrambled into one year is stressful and may limit your course options.
Frequently Asked Questions
No - one sitting produces one outcome. If your score meets the high cut score, you are awarded the RPFT. If it meets only the low cut score, you receive the CPFT. You do not receive both credentials simultaneously from a single exam. However, a CPFT holder can later sit for the exam again targeting the RPFT-level cut score.
Unanswered questions are scored as incorrect. The exam does not distinguish between a wrong answer and a blank one in your final score. Time management practice with a realistic timed test environment is essential preparation - aim to answer every question and flag uncertain ones to revisit if time permits.
No. Pretest questions are randomly distributed throughout the exam and are indistinguishable from scored questions. The NBRC uses this format to evaluate new items for future exam versions. Treat every question as scored.
The current PFT Detailed Content Outline became effective in October 2022. The NBRC periodically reviews and updates content outlines to reflect changes in clinical practice and guidelines. Always verify you are studying from the current published outline on the NBRC website before purchasing study materials.
The best preparation uses questions built specifically around the three PFT domains - Instrumentation/Equipment, Procedures, and Data Management - in the same proportions as the real exam. Visit our CPFT/RPFT practice test platform for domain-weighted question sets with detailed rationales. You can also review the full article on CPFT/RPFT Exam Format 2026: Questions, Time and Scoring for additional context on how to structure your preparation around the content outline.