CETI Requirements 2026: Eligibility, Prerequisites & How to Qualify

Which CETI This Article Covers

The acronym CETI is shared by several unrelated credentials, so a quick clarification saves candidates real confusion. On this site, CETI means the Council-certified Environmental Thermography Investigator, a credential administered by the American Council for Accredited Certification (ACAC) and accredited by CESB. It certifies practitioners who use infrared thermography to investigate buildings: roofs, exteriors, interiors and plumbing systems.

If you landed here looking for requirements for a different certification with the same letters, the details below will not apply to you. For background on the credential itself, see our overview pages What Is CETI? and What Does CETI Stand For?. This article focuses on a single question: what do you actually need to qualify, and in what order?

The Two-Year Eligibility Formula

ACAC's published eligibility standard is built on a combined-credit model. Applicants need two combined years of relevant science-related postsecondary education and field experience. In other words, the two years can be assembled from a mix of academic study and hands-on work rather than coming from a single source.

That structure makes the CETI reachable from several different backgrounds:

• Experience-heavy candidates: A building inspector, energy auditor or restoration professional who has used thermal imaging on the job may be able to document most or all of the two years through field work.
• Education-heavy candidates: Someone with relevant science-related postsecondary coursework can apply that study toward the combined total, provided they also meet the field experience floor described next.
• Blended candidates: Many applicants will combine a partial academic record with a stretch of practical investigation work.

The exact way ACAC credits a given course or job role is determined by the board's review of your submission, so treat the two-year figure as the threshold and your documentation as the proof. When in doubt about whether a particular course counts as "science-related," ask ACAC before you pay.

Why the One-Year Field Experience Floor Matters

The combined formula has an important guardrail. ACAC's eligibility FAQ requires at least one actual year of field experience. You cannot satisfy the two-year requirement with education alone, no matter how much coursework you have completed.

This is the single most common point of misunderstanding. A candidate with a strong academic record in physics or building science still needs a documented year of real investigative work. The reasoning is straightforward: the credential certifies someone who investigates buildings with thermal tools, and ACAC wants evidence that you have done that in practice.

Documentation You Must Assemble

The CETI application is documentation-driven. Plan to gather the following before you begin the online form:

1. Transcripts for any postsecondary education you are claiming toward the two-year total.
2. Verifiable investigation reports or contracts showing relevant investigations, consulting or report writing.
3. Four separate project sheets (covered in the next section).
4. The online application itself, using the Official CETI Application form.
5. Email verifications that confirm your claims.

Verification is the step candidates underestimate. Email verifications depend on other people, such as former supervisors, clients or colleagues, responding promptly. Contact them early, tell them what ACAC will ask, and give them the context they need so the verification does not become the reason you miss your deadline.

The Four Project Sheets

One of the most distinctive CETI requirements is the submission of four separate project sheets. These are your evidence that you have performed real thermographic investigations, and the four-sheet structure mirrors the credential's four investigation areas.

Note that ACAC describes the four sheets as separate, so plan four distinct projects rather than recycling a single job. If your career has leaned heavily toward roofs, for example, you may need to seek out plumbing or interior assignments before you apply. Our complete guide to the CETI exam domains explains what each of these four areas involves in more detail.

Application Mechanics, Fees and the Six-Month Clock

ACAC's process has no mandatory training course, but it does have a firm timeline. You must complete the application process, including the examination, within six months. That window starts to matter the moment you submit, so do not file a half-prepared application hoping to finish the paperwork later.

Because the retake fee is only $100, a failed attempt is financially recoverable, but the six-month limit means you should not plan on multiple attempts as a strategy. For a deeper look at budgeting, including how these fees compare to the value you can expect, read our CETI certification cost breakdown and the ROI analysis.

What the Examination Looks Like

Once your application clears, you face the exam itself. ACAC's general examination policy specifies closed-book, computer-delivered multiple-choice testing, with at least four answer choices per question. Delivery is handled through the testing provider, Kryterion, either at a test center or through secure online video proctoring.

The passing threshold is at least 75%, as verified in the current Official CETI Application. Because the exam is closed-book, you cannot rely on looking up thermal physics relationships or camera specifications during the test; you need working recall. Our guide to the CETI passing score and the discussion of how hard the exam is cover what that standard means in practice, and the page on exam dates and scheduling explains how to plan your sitting inside the six-month window.

If you want to test your recall under realistic conditions before you pay the exam fee, our CETI practice test lets you rehearse the multiple-choice format.

Competency Scope: Four Investigation Areas

ACAC lists application competencies organized under four headings: roof inspections, building exterior investigations, building interior investigations, and plumbing investigations. It is important to be honest about what is and is not known here. These four headings reproduce the issuer's listed competencies; they are not an exhaustive exam blueprint, they are unweighted, and the linked handbook page contains no syllabus text. Until ACAC supplies a complete blueprint, candidates should use this limited scope as their guide rather than assuming a specific number of domains or weighting.

Beyond the four investigation areas, ACAC's competency page also describes thermal and infrared physics, along with infrared-camera selection, calibration and operation. In practical terms, expect to be comfortable with:

• How infrared energy behaves and how surfaces emit, reflect and transmit it
• Choosing an appropriate infrared camera for a given investigation
• Calibrating and operating the camera so that readings are trustworthy
• Interpreting thermal patterns in roofs, exteriors, interiors and plumbing contexts

Board Approval and What Happens After You Pass

Passing the exam is necessary but not sufficient. ACAC states that certification requires unanimous board approval. That makes the CETI closer to a peer-reviewed credential than a pure test-out certification: your project sheets, verifications and supporting documents are evaluated as a package.

The practical implication is that sloppy paperwork can cost you even after a strong exam score. Write project sheets clearly, make sure your verifiers respond, and ensure your reports are legible and verifiable. A reviewer who cannot confirm what you did has little basis to approve.

Curious about how rare the credential is? ACAC's December 31, 2025 activity report lists 3 current CETI certifications. That is a count of current holders, not exam volume, and it should not be read as a pass rate. For what can and cannot be said about pass-rate data, see CETI pass rate: what the data shows.

Maintaining the Credential: Validity and Renewal

The CETI is valid for two years. Renewal costs $400. ACAC's central renewal procedure requires 40 renewal credits (RCs), made up of 10 for continued field activity and 30 hours of professional development.

There is a discrepancy you should know about. The credential page instead describes 20 professional-development hours annually. These two descriptions are not obviously identical, so confirm the current requirement directly with ACAC when you plan your renewal cycle rather than assuming either figure.

A Qualification Plan Built Around Your Gaps

Rather than a generic study calendar, sequence your preparation around the requirements above. Here is one way to structure roughly the first stretch of your effort, adapted to the four investigation areas.

If you are weighing whether to invest in formal instruction, remember that ACAC does not mandate a training course. Our CETI training overview discusses optional preparation routes, and our CETI jobs and salary guide pages cover where the credential tends to be useful professionally.

Frequently Asked Questions

Meeting the requirements is the first hurdle; the exam is the second. When your paperwork is in motion, build your recall with the CETI practice tests and revisit our guide to CETI requirements whenever ACAC updates its published criteria.