CRES Certification

What the CRES Credential Actually Is

CRES stands for Certified Radiology Equipment Specialist. It is a professional certification issued by the Association for the Advancement of Medical Instrumentation (AAMI) and administered through its ACI certification program. AAMI's overview page calls ACI the AAMI Certification Institute, while its FAQ uses the name AAMI Credentials Institute. Both names describe the same AAMI program, so you do not need to worry that you are looking at two different issuers.

The scope of the credential matters, because the acronym is shared by several unrelated certifications. This CRES is for biomedical equipment professionals who install, maintain, calibrate, and troubleshoot radiology and imaging equipment. It is not a radiologic technologist credential, which certifies people who perform imaging procedures on patients. It also has nothing to do with refrigeration-energy certification. If you came here after searching for other certifications that abbreviate to CRES, the details in this article apply only to the AAMI credential. For a plain-language orientation, see What Is CRES Certification? and What Does CRES Stand For?.

Who Hires Certified Radiology Equipment Specialists

Radiology equipment specialists work wherever imaging systems need to be installed, maintained, and kept safe and available. Typical employers fall into a few groups:

• Hospital and health-system clinical engineering departments, where in-house biomedical teams often hold a dedicated imaging specialist role.
• Independent service organizations (ISOs) that contract to maintain imaging fleets for hospitals and outpatient centers that prefer not to staff the capability internally.
• Imaging equipment manufacturers and their field service divisions, which employ field engineers who install and repair their own platforms.
• Outpatient imaging centers and multi-site radiology groups that run their own equipment and need technically credible staff or contractors.
• Military and government healthcare facilities, where biomedical equipment technology training is a common entry route.

Because the credential is a recognized way to document specialty competence, it tends to appear in job postings as preferred or, in some cases, required for imaging-focused roles. For a closer look at the job market, read CRES Jobs, and for compensation context see the CRES Salary Guide. For the question many technicians ask first, the CRES ROI analysis weighs the investment against career outcomes.

Eligibility Pathways and Candidate Status

CRES is not an entry-level exam you can sit for with no background. AAMI publishes three routes to full eligibility, all built around hands-on biomedical equipment technician (BMET) experience:

Two additional rules shape how candidates qualify. First, a specialty-experience requirement applies: at least 40% of your work during the preceding two years, or 25% during the preceding five years, must be in the designated specialty, here radiology equipment. Second, a bachelor's degree does not replace the work-experience requirement. If you claim the degree or military pathway, you must provide documentation of that education or training.

The full breakdown, including how documentation is handled, is in CRES Requirements: Eligibility, Prerequisites and How to Qualify.

Exam Format and How It Is Scored

The CRES examination consists of 165 multiple-choice questions with a three-hour time limit. It is closed-book, so no reference materials are allowed, though a simple calculator is permitted. That calculator allowance is a meaningful clue about content: you will encounter questions involving electrical relationships such as Ohm's law, power, and basic circuit calculations, and you should practice doing them efficiently.

Delivery is computer-based at approved Kryterion testing centers, scheduled through Webassessor. Plan on traveling to a physical testing site rather than testing from home.

How passing is determined

The exam uses a criterion-referenced standard set through the modified Angoff method. In practice, subject-matter experts judge how a minimally qualified candidate should perform on each item, and those judgments establish the passing standard. This means there is no guessed fixed percentage you can aim for, and the standard is about demonstrated competence rather than ranking you against other test takers. If you are curious about what this implies, see CRES Passing Score and CRES Pass Rate.

What the question style demands

With 165 questions in 180 minutes, you have a bit under eleven minutes for every ten questions. Single-best-answer questions in a technical field reward candidates who can recognize the correct concept quickly and who can reason through a scenario when the stem describes a symptom. Expect a mix of recall items (definitions, standards, component functions) and applied items (a described fault, what to check first, what the result implies). Practicing under timed conditions with realistic items on our CRES practice test site helps you calibrate pacing before test day.

The Six Content Areas and Where the Points Are

AAMI publishes six content areas and labels every percentage as approximate. The three largest areas are each roughly 25%, together making up about 75% of the exam. That concentration should drive how you divide your time. The sections below follow the issuer's six domains; for a deeper dive, see CRES Exam Domains: Complete Guide to All 6 Content Areas.

Note that the issuer's current live objectives are the source for these weights. Older material that circulates online may show different allocations from an earlier outline, so rely on AAMI's current published content outline rather than a study resource that cites 2018 weights.

Registration, Fees and Testing Windows

CRES is offered in two regular testing windows each year: May 1-15 and November 1-15. Registration is built around application deadlines that fall before each window, so you cannot decide at the last minute.

For the November 1-15, 2026 window, the application deadline is October 16. Late registration remains open until October 23 and carries a $50 late fee. Always confirm current dates on AAMI's certifications page before you plan around them, since windows and deadlines are reissued each cycle. Our guides on CRES exam dates and CRES certification cost go deeper on scheduling and budgeting, including the member versus nonmember decision.

Sequencing Your Preparation Around the Blueprint

You do not need an elaborate method; you need an order that respects the weights. A reasonable sequence for a technician with working imaging experience looks like this, and a more complete approach appears in the CRES Study Guide.

Scheduling Problem Solving late is deliberate: those scenarios pull from every other domain, so they are most productive once the foundations are in place. Use the CRES cheat sheet as a final review, and test your readiness with timed sets on our practice exams. To gauge how demanding the exam is for your background, see How Hard Is the CRES Exam?.

Keeping the Credential: Renewal Mechanics

Passing the exam is not the end of your obligations. CRES certification is maintained through continuing education on a three-year reporting cycle:

• Earn at least 30 ACI CEUs in each three-year cycle.
• At least 15 of those must be in Category IV: Professional Development.
• Report your activity through My Active CEU Journal.
• Pay the renewal fee: $100 for members, $150 for nonmembers.
• Per the current FAQ, CEUs must be earned by December 31 of the recertification year.

The length and end date of your very first cycle can differ from later ones. An earlier handbook described the first cycle as the remainder of your certification year plus three full calendar years, ending December 31, but that detail could not be revalidated against the newest handbook. The practical advice is simple: use the expiration date ACI assigns to you rather than calculating your own, and begin logging CEUs as soon as you are certified instead of waiting until the final year.

Frequently Asked Questions