- Which RTT This Sheet Covers
- The Exam at a Glance
- Scoring Rules You Must Not Confuse
- The Blueprint in Numbers
- Domain 1: Patient Care Facts
- Domain 2: Safety Facts
- Domain 3: Procedures Facts
- Eligibility and Clinical Requirements
- Fees, Attempts and Deadlines
- Staying Certified After You Pass
- Using the Sheet: A Domain-Weighted Review Order
- Frequently Asked Questions
- The exam has 230 questions: 200 scored and 30 unscored pilot items, with 230 minutes of answering time.
- A passing score is 75 on ARRT's 1-99 scaled range, not 75% of questions correct.
- Procedures carries 103 of 200 scored questions, more than Patient Care (46) and Safety (51) combined.
- You need an associate degree or higher, conferred before the exam, plus an ARRT-verified radiation therapy program.
Which RTT This Sheet Covers
This cheat sheet covers Registered Technologist - Radiation Therapy, the radiation therapy credential issued by the American Registry of Radiologic Technologists (ARRT). In ARRT's own terminology the discipline is Radiation Therapy (T), and "RTT" is simply the abbreviation used on this site. It is earned through the ARRT primary eligibility pathway, not as a postprimary examination layered on top of a Radiography credential.
If you are still sorting out terminology, our explainers on what RTT is and what RTT stands for cover the naming. Everything below applies only to the ARRT radiation therapy examination, and the content scope is the Radiation Therapy Examination Content Specifications that control exams through January 31, 2027.
The Exam at a Glance
| Item | What to Know |
|---|---|
| Issuer | American Registry of Radiologic Technologists (ARRT) |
| Delivery | Pearson VUE test centers, computer-based |
| Total questions | 230 (200 scored + 30 unscored pilot questions) |
| Answering time | 230 minutes |
| Appointment length | 250 minutes, including tutorial, nondisclosure agreement and survey |
| Format | Primarily single-best-answer multiple choice; possible alternative item formats and image-based questions |
| Book policy | Closed book |
| Calculator | On-screen basic and scientific calculators; Pearson can supply a basic four-function calculator on request; personal calculators prohibited |
Two practical behaviors matter on test day. First, you must answer each item before advancing, so there is no skipping into blank space. Second, you can flag any answer and return to it, which means a smart pacing plan is to commit to your best answer immediately, flag the uncertain ones, and use leftover time for review.
Because the 30 pilot questions are unscored and not identified, treat every item as if it counts. The ARRT handbook also describes multiple-response and ordered-response formats, so practice reading the question stem for how many answers it wants and whether sequence matters. For a candid look at how this format feels in practice, see how hard the RTT exam really is.
Scoring Rules You Must Not Confuse
The 75 Is a Scaled Score
The passing score is 75 on ARRT's 1-99 scaled-score range. It is not "75% correct." Raw performance is converted to a scaled score so that candidates are judged against the same standard even if the questions they see differ in difficulty. A revised examination cut-score standard took effect on February 1, 2025; the reported passing score remains 75 scaled. The full explanation is in our guide to the RTT passing score.
What the Pass-Rate Data Shows
In ARRT's Annual Exam Report for 2025, the first-time candidate pass rate was 77.1% (n=958). That figure describes first-time candidates only; do not extend it to repeaters or to other years. For context and caveats, read what the pass-rate data shows.
Attempt Limits
You get three examination attempts within three years of the opening of your initial examination window. That is a different clock from the application deadline covered below, and mixing the two up is a classic planning error.
The Blueprint in Numbers
ARRT publishes scored-question allocations as counts out of 200. Keep them as counts; do not convert them into invented percentages.
| Domain / Category | Scored Questions |
|---|---|
| Domain 1: Patient Care | 46 |
| Patient Interactions and Management | 29 |
| Patient and Medical Record Management | 17 |
| Domain 2: Safety | 51 |
| Radiation Physics and Radiobiology | 21 |
| Radiation Protection, Equipment Operation, and Quality Assurance | 30 |
| Domain 3: Procedures | 103 |
| Treatment Sites and Tumors | 26 |
| Treatment Volume Localization | 18 |
| Prescription and Dose Calculation | 24 |
| Treatments | 35 |
The single largest category is Treatments (35), followed by Patient Interactions and Management (29), Radiation Protection, Equipment Operation, and Quality Assurance (30), and Treatment Sites and Tumors (26). For a fuller walk-through of each area, see the complete guide to all three RTT content areas.
Domain 1: Patient Care Facts
Patient Care (46 scored questions)
This domain splits into Patient Interactions and Management (29) and Patient and Medical Record Management (17). It rewards clear judgment about how a therapist interacts with oncology patients across a course of treatment.
- Communicating with patients who are anxious, in pain, or experiencing treatment side effects
- Assessing patient status and recognizing when to involve other members of the care team
- Maintaining accurate, timely documentation of treatment delivery and patient condition
- Verifying patient identity and treatment records before delivery
- Respecting confidentiality and informed-consent principles within the radiation therapy setting
Questions here often present a scenario and ask for the most appropriate action. The "best answer" is typically the one that protects the patient, keeps the record accurate, and escalates appropriately rather than improvising outside your scope.
Domain 2: Safety Facts
Safety (51 scored questions)
Safety combines Radiation Physics and Radiobiology (21) with Radiation Protection, Equipment Operation, and Quality Assurance (30). The second category is the heavier of the two.
- Radiation physics fundamentals as they apply to external-beam delivery
- Radiobiology concepts that explain why dose is fractionated and how tissues respond
- Protection principles for patients, staff and the public
- Safe operation of treatment and simulation equipment
- Quality assurance checks and recognizing when equipment performance is out of tolerance
The content specifications state that SI units are primary, so build your recall around SI usage first. Brachytherapy coverage is deliberately limited to basic common-use concepts, surrounding-tissue-dose considerations and radiation-protection concepts. It does not extend to detailed procedures or isotope characteristics, so do not spend weeks memorizing isotope tables.
Domain 3: Procedures Facts
Procedures is the center of gravity: 103 of 200 scored questions, just over half the exam. It is also where classroom and clinical experience pay off most directly.
Treatment Sites and Tumors (26)
Know the anatomy and typical treatment considerations for common disease sites.
- Common tumor sites and the anatomy surrounding them
- Critical structures near target volumes and why they limit dose
- Basic staging concepts only; the specifications exclude site-specific staging detail
Treatment Volume Localization (18)
This is the simulation-and-imaging side of planning.
- Patient positioning and immobilization for reproducible setup
- Simulation procedures and the role of imaging in defining treatment volumes
- Reference marks and how they carry setup information to the treatment unit
Prescription and Dose Calculation (24)
Expect calculation-driven items, so be comfortable with the on-screen calculator.
- Reading and interpreting a prescription, including fractionation
- Performing and checking dose calculations
- Understanding how treatment parameters affect delivered dose
Treatments (35)
The largest single category on the exam.
- Delivering external-beam treatments accurately and safely
- Verifying setup, imaging and treatment parameters before delivery
- Using accessory devices and recognizing special treatment techniques
- Monitoring the patient and the treatment throughout delivery
Specific CPT codes are excluded from the content specifications, so billing-code memorization is not worth your time for this exam.
Key Takeaway
Treatments (35) plus Prescription and Dose Calculation (24) account for 59 scored questions, more than the entire Patient Care domain and more than the entire Safety domain. If you must prioritize, weight your review toward these two categories while keeping the other domains from slipping.
Eligibility and Clinical Requirements
Primary eligibility has three pillars: education, clinical competency and ethics. You can walk through the full pathway in our RTT requirements guide; here is the compressed version.
- Degree: An associate degree or higher from an ARRT-recognized accredited institution. The degree may be in any major and must be conferred before the examination.
- Program: Completion of an ARRT-verified radiation therapy educational program and its didactic and clinical competencies.
- Ethics: Compliance with ARRT ethics requirements.
- Radiography: An existing Radiography credential is not a universal prerequisite for this pathway.
- Timing: The degree must be earned and the application submitted no more than three years after program completion.
Clinical Competency Checklist
| Requirement | Quantity |
|---|---|
| CPR plus other patient-care activities | CPR plus six other patient-care activities |
| Quality-control activities | Five |
| Treatment-simulation procedures | Six |
| Dose calculations for treatment plans | Six plans |
| Accessory devices fabricated | Three |
| Special treatment procedures (participation) | Four |
| Specialized simulation procedure | One |
| Specialized accessory-device construction process | One |
| Radiation treatment procedures | 16 total, at least 13 on patients, no more than three simulated |
The program director or designee must verify clinical competency through in-person direct observation. Remote or virtual observation is not accepted. If you are comparing program options, our overview of RTT training is a useful starting point.
Fees, Attempts and Deadlines
| Item | Amount / Rule |
|---|---|
| Initial application | $225 USD |
| Examination reapplication | $200 USD |
| Annual renewal | $65, regardless of the number of ARRT credentials held |
| Exam attempts | Three, within three years of the opening of the initial examination window |
These are the ARRT-side fees from the current fee schedule; for the wider picture including program costs and study materials, see the RTT certification cost breakdown. For how testing windows and scheduling work, use the RTT exam dates guide, and confirm all current details directly with ARRT and Pearson VUE before booking.
Staying Certified After You Pass
Passing the exam is the start of a maintenance cycle, not the end of one.
- Annual renewal: $65 per year, regardless of how many ARRT credentials you hold.
- Ethics: Continuing compliance with ARRT ethics requirements.
- Continuing education: 24 approved CE credits per two-year biennium, counted per biennium, not per credential.
- Continuing Qualifications Requirements (CQR): Credentials earned on or after January 1, 2011 also require CQR every 10 years, consisting of a professional profile, a structured self-assessment and any prescribed CE. ARRT also permits accepting the maximum CQR CE prescription instead of taking the self-assessment.
Thinking about the long game? Our analyses of RTT earnings and whether the credential is worth it put these ongoing costs in context, and RTT jobs covers where graduates typically find work.
Using the Sheet: A Domain-Weighted Review Order
This is the one place where study planning belongs. The sequence below follows the blueprint counts, so the heaviest content gets the most calendar time. For a broader plan, see the RTT study guide.
Procedures: Treatments and Dose Calculation
- Rework prescription and dose calculation problems using the on-screen calculator interface
- Review setup verification, imaging and delivery sequences
Procedures: Sites, Tumors and Localization
- Pair each common disease site with its critical structures and setup considerations
- Review simulation, immobilization and reference marking
Safety
- Radiation protection, equipment operation and quality assurance first (30 questions)
- Then physics and radiobiology (21 questions), staying in SI units
Patient Care and Full Review
- Scenario practice for patient interactions and record management
- Timed mixed sets covering all three domains
When you reach the timed-set stage, take a full-length run on the RTT practice test site so the 230-question pacing feels familiar before exam day, and revisit the practice question bank for any category where your results lag.
Frequently Asked Questions
No. The passing score is 75 on ARRT's 1-99 scaled-score range. Raw performance is converted to a scaled score, so 75 does not mean 75% of questions answered correctly.
200 of the 230 questions are scored. The other 30 are unscored pilot questions, and they are not identified, so answer every item as though it counts.
No. An existing Radiography credential is not a universal prerequisite. The primary pathway requires an associate degree or higher, an ARRT-verified radiation therapy program with its didactic and clinical competencies, and ethics compliance.
Procedures, with 103 of 200 scored questions. Safety has 51 and Patient Care has 46. Within Procedures, Treatments is the largest category at 35 questions.
Three attempts within three years of the opening of your initial examination window. This is separate from the three-year limit on earning your degree and submitting your application after program completion.
For a more general orientation to the credential, start with RTT certification or what RTT certification is, and use this page as your one-stop refresher in the final weeks before test day.