- The RSC Exam at a Glance
- Eligibility, Fees and Registration Facts
- Domain Weights: Where the Points Live
- Domain 1 Cheat Sheet: RAM License (About 50%)
- Domain 2 Cheat Sheet: CT (About 15%)
- Domains 3-5: X-ray/Fluoroscopy, MRI Safety, Optimizing Exposure
- Test-Day Mechanics
- Passing Score and Pass-Rate Facts (and What Is Not Known)
- Validity, Renewal and Recertification
- Sequencing Your Review by Domain
- Frequently Asked Questions
- RSC is Radiation Safety Certification from the NMTCB; the post-primary credential designation is NMTCB(RS).
- The exam has 200 computer-based multiple-choice questions in 210 minutes, closed book, with a USD 225 nonrefundable fee.
- RAM License content is approximately 50% of the exam; CT, X-ray/Fluoroscopy, MRI, and Optimizing Exposure/Other Topics fill the rest.
- No numeric passing score or current pass rate was verified from issuer sources, so treat any quoted figure with suspicion.
The RSC Exam at a Glance
This page condenses the facts that matter most for Radiation Safety Certification into a single review. The credential is issued by the Nuclear Medicine Technology Certification Board (NMTCB), and its official post-primary designation is NMTCB(RS). It is not CNMT, and it is not NMTCB(CT). If you are new to the name, start with What Is RSC Certification? for the background, then come back here for the compressed review.
| Item | Fact |
|---|---|
| Issuer | Nuclear Medicine Technology Certification Board (NMTCB) |
| Designation | NMTCB(RS) |
| Test provider | IQT, Inc. / Iso-Quality Testing, at proctored testing centers |
| Format | 200 computer-based multiple-choice questions; four or five options, one correct answer |
| Time | 210 minutes, closed book |
| Fee | USD 225, application/examination, nonrefundable |
| Retake limit | One attempt per twelve calendar months |
| Results | Mailed in approximately four to six weeks |
| Validity | Ten years, with annual registration and fees |
The content outline behind the exam is the NMTCB Radiation Safety Certification Examination Content Outline (2017 FINAL), which the issuer still links from its current instructions. Weights and administration details come from the NMTCB Radiation Safety exam information page. The outline's filename carries the 2017 date; that is the document the issuer points to, and no other NMTCB exam's revision should be substituted for it.
Eligibility, Fees and Registration Facts
Initial eligibility has two parts, and both must be met.
- A qualifying credential held at least two years. The qualifying credentials are an active NMTCB, ARRT(N/R/T), or CAMRT(RTNM/RT/RTT) credential.
- One calendar year of radiation-safety duties. These are documented by supervisor or Radiation Safety Officer (RSO) attestation.
The fee is USD 225, nonrefundable. For the full picture of what you will spend beyond the exam fee, see RSC Certification Cost 2026: Complete Pricing Breakdown, and for a deeper eligibility walkthrough use RSC Requirements 2026: Eligibility, Prerequisites & How to Qualify.
The 2026 dates, stated plainly
The 2026 examination window was August 13-15, with a July 1, 2026 eligibility deadline. Both are in the past as of the October 15, 2026 research date, so neither is an upcoming appointment. An earlier winter newsletter announced August 14-16; the current exam page and the later summer newsletter supersede that, and both agree on August 13-15. No future sitting should be assumed. Check the issuer directly and see RSC Exam Dates 2026: Testing Windows, Deadlines & Scheduling for how to track announcements.
Domain Weights: Where the Points Live
All five displayed percentages are approximate issuer allocations. The issuer prints them with a tilde, which means they are not exact item quotas. Do not calculate "exactly 100 questions on RAM License." Use the weights to prioritize, not to count.
| Domain | Approx. Weight | Level |
|---|---|---|
| 1. Content Pertaining to a RAM License | ~50% | Expertise area |
| 2. Content Pertaining to CT | ~15% | Expertise area |
| 3. Content Pertaining to X-ray & Fluoroscopy | ~15% | Competence, not expertise |
| 4. Content Pertaining to MRI Safety | ~10% | Competence, not expertise |
| 5. Optimizing Radiation Exposure / Other Topics | ~10% | Not specified |
The expertise-versus-competence labels come straight from the outline and are among the most useful signals in it. For RAM License and CT, expect to be tested as someone who could run the program or defend the protocol. For X-ray/Fluoroscopy and MRI Safety, expect to be tested as someone who understands the hazards and can recognize correct practice, without being the designated expert. A longer treatment lives in RSC Exam Domains 2026: Complete Guide to All 5 Content Areas.
Domain 1 Cheat Sheet: RAM License (About 50%)
Content Pertaining to a RAM License (Expertise Area)
Roughly half the exam. This is the domain that rewards people who have actually worked under, or administered, a radioactive materials license. Think in terms of the license as the governing document and the radiation safety program as the machinery that keeps the facility within it.
- What the license authorizes, restricts, and requires of the licensee
- The RSO's role and responsibilities, and the Associate RSO's relationship to it
- Program elements a licensee must maintain: surveys, dosimetry, inventory, postings, labeling, training
- Receipt, storage, transfer, and disposal of radioactive material
- Waste handling and decay-in-storage logic
- Incident, spill, and misadministration response and reporting
- Record-keeping: what must be kept, and the reasoning behind retention
Because the outline marks this as an expertise area, scenario questions in this domain are where candidates with only textbook familiarity tend to struggle. Questions that ask what the RSO must do, what must be documented, or what action is required first reward applied judgment more than recall. If your day job never touched license administration, this is where your preparation time should be heaviest.
Domain 2 Cheat Sheet: CT (About 15%)
Content Pertaining to CT (Expertise Area)
CT is the other expertise domain. The framing is radiation safety, not image interpretation: protecting patients, staff, and the public while keeping dose appropriate to the clinical question.
- How CT dose differs in character from planar and projection imaging
- Scan parameters and protocol choices that move dose up or down
- Pediatric and special-population considerations in protocol design
- Shielding and room design concepts for CT suites
- Staff exposure behavior around a CT scanner, including hybrid (PET/CT, SPECT/CT) settings
- Dose-tracking and review practices
Nuclear medicine candidates often know hybrid CT from the technologist's chair, which is a good start but not enough. The exam expects the safety-program view: why a protocol is set the way it is, who reviews it, and what a safety officer would check.
Domains 3-5: X-ray/Fluoroscopy, MRI Safety, Optimizing Exposure
Domain 3: X-ray & Fluoroscopy (about 15%, competence but not expertise)
X-ray & Fluoroscopy
Competence-level means you should recognize correct safety practice and the principles behind it, not design the program.
- Principles of time, distance, and shielding as applied to x-ray rooms and fluoroscopic procedures
- Why fluoroscopy produces higher staff exposure potential than routine radiography
- Protective apparel and its limits
- Personnel monitoring practices for fluoroscopy workers
- Basic operator techniques that reduce dose to patient and staff
Domain 4: MRI Safety (about 10%, competence but not expertise)
MRI Safety
This is the domain that surprises radiation-focused candidates, because MRI uses no ionizing radiation. The hazards are different, and the exam tests that you can tell them apart.
- The static magnetic field and the projectile hazard
- Why the magnet is always "on," and what that means for access control
- Zoning and screening concepts for patients, staff, and visitors
- Implanted devices and other screening considerations
- Other MRI-specific hazards beyond the static field
Domain 5: Optimizing Radiation Exposure / Other Topics (about 10%)
Optimizing Radiation Exposure / Other Topics
The catch-all domain, but optimization is a coherent theme. Expect questions that cut across modalities and ask whether you can apply the same safety philosophy everywhere.
- The ALARA philosophy and how it is operationalized in a program
- Dose-limit concepts and monitoring logic
- Reducing exposure through procedure, design, and administrative controls
- Miscellaneous safety topics that do not fit neatly into another domain
Key Takeaway
The two expertise domains (RAM License and CT) together are roughly 65% of the exam by approximate weight. The two competence-only domains (X-ray/Fluoroscopy and MRI Safety) are roughly 25%. Spend your depth where the outline says you are expected to be the expert.
Test-Day Mechanics
- Bring: your admission letter, valid photo identification that matches your registration, and an approved calculator.
- Calculator rules: noiseless, battery or solar powered, and without alphabetic text-storage capability. Calculators are not supplied, so arrive with your own.
- Not allowed: outside books and notes. Authorized scratch paper is provided.
- Navigation: an answer is required before you can advance, but you can mark questions for review and change answers.
- Pacing: 210 minutes for 200 questions works out to a little over a minute per question, with calculation items and long scenarios eating more than their share.
Because an answer is required to advance, never leave a question blank. Make your best choice, mark it, and return if time allows. The calculator matters in this exam because decay, shielding, and dose-rate arithmetic are fair game; practice with the same kind of basic calculator you will carry in.
Passing Score and Pass-Rate Facts (and What Is Not Known)
Two things are worth stating carefully here, because this is the topic most likely to attract made-up numbers.
There is historical issuer reporting from the NMTCB Report in the Journal of Nuclear Medicine Technology (46(4), 9A, 2018):
| Cohort | Passed / Tested | Reported Rate |
|---|---|---|
| November 2017 | 55 of 68 | 81% |
| August 2018 | 51 of 65 | 79% |
Note the discrepancy: 51 of 65 computes to about 78.46%, while the report states 79%. The source figure is preserved as printed rather than silently corrected. More importantly, these are small historical cohorts and are not current pass-rate estimates. For context on how to interpret them, read RSC Pass Rate 2026: What the Data Shows and How Hard Is the RSC Exam? Complete Difficulty Guide 2026.
Validity, Renewal and Recertification
- Validity: ten years, with annual registration and fees.
- At the ten-year mark: a qualifying RSO/Associate RSO RAM-license listing, or attested radiation-safety duties within the preceding seven years, supports a USD 100 recertification application. Without that, re-examination applies.
- If the credential expires: requalification and examination are required.
- Continuing education: successfully completing the RS post-primary exam earns 24 CE under NMTCB continuing competence policy.
If you are weighing whether the credential pays for itself, Is the RSC Certification Worth It? Complete ROI Analysis 2026 and RSC Salary Guide 2026: Complete Earnings Analysis walk through the reasoning. Be aware that broader NMTCB/SNMMI-TS workforce observations published in the summer 2026 newsletter do not establish an RS-specific salary premium. For roles where the credential is relevant, see RSC Jobs.
Sequencing Your Review by Domain
The approximate weights suggest an order of attack. This is a framework, not a rigid schedule; adjust it to what you already know from your day job.
RAM License foundations
- Start here because it is about half the exam and the deepest expertise area
- Work license administration and RSO responsibilities first, then waste, surveys, and incident response
CT, then X-ray/Fluoroscopy
- Treat CT at expertise depth; treat X-ray/Fluoroscopy at competence depth
- Drill the calculation-style items with your actual exam calculator
MRI Safety, optimization, mixed review
- Give MRI Safety dedicated time even though it is smaller, since its hazards are unfamiliar to most radiation-trained candidates
- Finish with mixed timed sets in the 200-question format
For a fuller plan, see RSC Study Guide 2026: How to Pass on Your First Attempt, and for structured exam-style practice use the RSC practice tests. If you want to simulate the pacing, work a full timed set from the main practice test site before you commit to a sitting. Since you only get one attempt per twelve calendar months, readiness matters more than speed. For training options, see RSC Training.
Frequently Asked Questions
It stands for Radiation Safety Certification, issued by the NMTCB, with the post-primary designation NMTCB(RS). See What Does RSC Stand For? for more on the name.
There are 200 computer-based multiple-choice questions with 210 minutes allowed. The exam is closed book, each item has one correct answer among four or five options, and you must answer before advancing, though you can mark items and change answers.
Content Pertaining to a RAM License, at approximately 50%. CT and X-ray/Fluoroscopy are each approximately 15%, while MRI Safety and Optimizing Radiation Exposure/Other Topics are each approximately 10%. All are approximate allocations, not exact item quotas.
No numeric passing score or current pass rate was verified in the retrieved issuer sources. Historical reports of 81% (November 2017) and 79% (August 2018) describe small past cohorts and should not be treated as current estimates.
The 2026 window (August 13-15) and its July 1, 2026 eligibility deadline have already passed, and no future sitting is confirmed here. Check the NMTCB directly for the next announced window.