What Is A RTN?

What a RTN Actually Is

On this site, RTN is shorthand for Registered Technologist - Nuclear Medicine Technology. It is the credential held by technologists who have passed the American Registry of Radiologic Technologists (ARRT) examination in the Nuclear Medicine Technology discipline and met the registry's education, clinical and ethics requirements. A technologist holding it prepares and administers radiopharmaceuticals, operates gamma cameras and PET or SPECT systems, and produces the diagnostic images physicians use to evaluate organ function, cardiac perfusion, thyroid disease, cancer spread and more.

One note on terminology: "RTN" is the abbreviation this site assigns, not the designation ARRT itself uses. ARRT's official discipline name is Nuclear Medicine Technology, shown with the letter (N) after a technologist's name. If you search the web for "RTN," you will run into other, unrelated credentials that happen to share the acronym. Everything in this article concerns only the ARRT nuclear medicine credential. For a shorter orientation to the acronym itself, see our pages on what RTN stands for and RTN meaning.

Who Issues It and How It Differs From Look-Alikes

The credential is issued by ARRT, and the exam is delivered at Pearson VUE test centers. The most common point of confusion in nuclear medicine is that there are two separate national certifying routes: ARRT's Nuclear Medicine Technology credential and the NMTCB's CNMT. They are different credentials from different organizations, with their own applications, fees, content outlines and maintenance rules. This article covers the ARRT route only, and the facts below should not be assumed to apply to the other.

Who Can Sit for the Exam

ARRT's primary eligibility pathway has three pillars: education, clinical competency and ethics. The full walkthrough lives in our RTN requirements guide, but the essentials are:

• Degree: an associate degree or higher from an ARRT-recognized accredited institution. The degree may be in any major, but it must be conferred before you take the examination.
• Program: completion of an ARRT-verified nuclear medicine technology educational program, including its didactic coursework and clinical competencies.
• Ethics: compliance with ARRT's ethics requirements, which are reviewed as part of the application.
• Timing: the degree must be earned and the application submitted no more than three years after completing the program.

That three-year application deadline is easy to confuse with a different clock. After you are approved, you get a separate window of three examination attempts within three years of the opening of your initial examination window. The first clock governs when you must apply; the second governs how long you have to pass. Read the dates carefully, and check the RTN exam dates guide for scheduling details.

The Clinical Competencies Behind the Credential

The clinical component is what separates this credential from a purely academic qualification. Your program must document that you performed a defined set of activities under observation:

• Eight general patient-care activities, including CPR certification
• Five quality-control activities
• 25 different diagnostic and therapeutic procedures

No more than five of those 25 procedures may be simulated. The program director or a designee must verify clinical competency through in-person direct observation. Remote or virtual observation is not accepted. If you are comparing programs, ask how many procedure types the clinical sites can realistically give you hands-on exposure to, because a thin clinical rotation can delay sign-off.

How the Exam Is Built and Delivered

Structure and timing

The examination contains 230 questions. Of these, 200 are scored and 30 are unscored pilot questions that ARRT uses to evaluate future items. You cannot tell which are which, so treat every question seriously. You have 230 minutes of answering time, and the full appointment is 250 minutes because it includes a tutorial, a nondisclosure agreement and a survey.

Question styles

The exam is computer-based and primarily uses single-best-answer multiple-choice questions. Image-based questions can appear, and ARRT's handbook also describes multiple-response and ordered-response formats, so be ready for items where more than one answer is required or where you must sequence steps. Expect camera images, scan displays and workflow-style scenarios alongside straightforward recall.

Rules at the test center

• The exam is closed book.
• Basic and scientific on-screen calculators are available, and Pearson can supply a basic four-function calculator on request. Personal calculators are prohibited.
• You must answer each item before advancing, but you may flag questions and revisit them.

The calculator point deserves practice: decay, dose and activity-concentration problems are routine in nuclear medicine, so rehearse them using only the on-screen tools so that nothing about the interface slows you down on test day. For a read on overall difficulty, see how hard the RTN exam is.

The Four Content Categories

ARRT organizes the exam into four official major content categories. For examinations through January 31, 2027, the controlling source is the Nuclear Medicine Technology Examination Content Specifications (version 2021.02.24, effective January 1, 2022). These are exam content categories, not a preparation curriculum, and the allocations below are scored-question counts out of 200. A deeper breakdown is in the RTN exam domains guide.

Notice the weighting. Procedures alone accounts for 118 of the 200 scored items, which is more than the other three domains combined. A candidate who is strong on safety and patient care but shaky on cardiac stress protocols, thyroid and oncology imaging, or radiopharmaceutical characteristics is gambling with the exam. Within Procedures, radionuclides and radiopharmaceuticals is the single largest sub-block at 28 questions, so know your agents, their uses, and the rationale behind each study.

Scoring and Pass-Rate Context

ARRT reports results on a scaled range of 1 to 99, and the passing score is 75. This is a scaled score, not 75 percent correct, because raw performance is converted to account for differences in difficulty between exam forms. A revised cut-score standard took effect February 1, 2025, though the reported passing score remains 75 scaled. Our RTN passing score guide explains how to interpret a score report.

On outcomes, ARRT's Annual Exam Report for 2025 lists a 64.7 percent first-time pass rate for the discipline, based on 439 first-time candidates. That figure reflects one year and one cohort, so use it as a rough indicator of seriousness rather than a prediction. More context is in the RTN pass rate analysis.

Fees and the Registration Mechanics

The initial application fee covers your first examination attempt. If you need another try, a reapplication fee applies, and you are limited to three attempts within three years of the opening of your initial examination window. The annual renewal fee is the same regardless of how many ARRT credentials you hold. For the full financial picture, including what to budget beyond ARRT's fees, see the RTN certification cost breakdown.

Staying Registered After You Pass

Passing the exam is the start of an ongoing obligation, not the end of one. To keep your certification and registration current, you must:

• Renew annually ($65, regardless of the number of ARRT credentials)
• Continue to comply with ARRT's ethics requirements
• Earn 24 approved continuing education credits per two-year biennium, counted per biennium and not per credential

Credentials earned on or after January 1, 2011 also carry Continuing Qualifications Requirements (CQR) every 10 years. CQR consists of a professional profile, a structured self-assessment and any prescribed CE. ARRT also lets you accept the maximum CQR CE prescription in place of taking the self-assessment, which gives you a choice about how to meet the requirement.

Where RTNs Work

Registered nuclear medicine technologists are employed wherever diagnostic and therapeutic radiopharmaceuticals are used:

• Hospitals, including dedicated nuclear medicine departments and combined radiology services
• Outpatient imaging centers and physician-owned practices
• Cardiology practices running myocardial perfusion and stress imaging
• Oncology and PET facilities performing staging and treatment-response imaging
• Academic medical centers and research programs
• Radiopharmacies, where technologists prepare and dispense doses

Hiring managers typically want the credential in hand plus demonstrated familiarity with the modalities they run. If you are exploring openings, our RTN jobs overview covers the employment landscape, and the salary guide and ROI analysis help you weigh the investment.

Sequencing Your Preparation

Rather than studying the four domains in textbook order, sequence them by exam weight and by how much each depends on the others. Because Procedures is so heavy and relies on radiopharmaceutical knowledge, start there. A sensible order follows.

For a complete plan, see the RTN study guide and the one-page RTN cheat sheet, and use our RTN practice tests to find weak spots by domain. Since the exam is image-heavy, make sure your practice includes image-based items rather than text-only recall.

Frequently Asked Questions