CIES Passing Score 2026: Exactly What You Need to Pass

The Number: 75% on a 120-Question Exam

Candidates searching for the passing score of the Council-certified Indoor Environmental Supervisor (CIES) credential want one clean figure, and the issuer provides it: 75%. The credential is issued by the American Council for Accredited Certification (ACAC) through its CIES Certification Board, and the program is accredited by the Council for Engineering and Scientific Specialty Boards (CESB). The examination is a closed-book, computer-delivered written test of 120 multiple-choice questions, each with at least four answer options, and candidates have three hours to finish.

That is the entire official scoring statement in plain terms. There is no published scaled-score range, no stated minimum per section, and no practical assessment layered on top. If you are still orienting yourself on what the credential covers, the overview at What Is CIES Certification? is a useful starting point, and the full eligibility picture lives in CIES Requirements 2026: Eligibility, Prerequisites & How to Qualify.

What 75% Means in Practice

On a 120-question exam, 75% works out to 90 correct answers if every item counts toward your score. That arithmetic comes with a caveat: ACAC does not publish how many items are scored versus unscored, so the exact raw-score equivalent of the cutoff is not something you can pin down in advance. If some items are unscored pretest questions, the number of scored items is smaller than 120, and the correct-answer count needed shifts accordingly.

The practical takeaway is that you should never study toward "exactly 90." Because you cannot tell which questions count, every question deserves full effort, and your practice-test results should clear 75% with a comfortable margin before you sit for the real thing.

How Modified Angoff Sets the Bar

The 75% threshold was set with the Modified Angoff method. In this approach, a panel of subject-matter experts reviews each exam item and estimates the probability that a minimally qualified candidate would answer it correctly. Those judgments are aggregated into the cut score. Two consequences follow for you:

• The bar is criterion-referenced. You are measured against a competence standard, not against the other people testing that week. A strong cohort does not raise the bar, and a weak one does not lower it.
• The panel is thinking about a minimally qualified supervisor. Questions are written around what a working indoor environmental supervisor must do competently, which means scenario judgment on engineering controls, cleaning and removal methods, worker safety and regulations rather than trivia recall.

Because the standard is competence-based, the most reliable preparation is genuine fluency in the regulatory and technical material. If you want a sense of how demanding that material feels, see How Hard Is the CIES Exam? Complete Difficulty Guide 2026.

What the Issuer Does Not Publish

A trustworthy passing-score guide should say what is missing as clearly as what is known. For the CIES exam, the following items could not be verified from ACAC's public materials:

• Domain weights. The five competency headings are published, but no percentages or highest-weighted area appear in public documents. The handbook says the board prescribes an exam blueprint, yet no public chart reproduces it.
• A numerical 2025 or 2026 pass rate. ACAC's 2025 certification activity report shows dashes for CIES applicants and pass ratio, and CIES is omitted from the 2025 exam pass ratio report. A dash is not a 0% pass rate. It simply means no usable figure was reported.
• A consistent historical rate. ACAC's 2024 reports conflict: one shows 2 exams taken and 2 passed, while another lists 2 applicants at 0%. With only two candidates in either report, neither figure says anything reliable about difficulty.
• A separately identified 2026 exam version. The public handbook page is undated.

For a fuller treatment of the statistics problem, read CIES Pass Rate 2026: What the Data Shows. The short version: tiny candidate volumes mean pass-rate numbers are noise, and the 75% cut score is the only hard number you can plan around.

Where Your Points Come From: Five Competencies

ACAC publishes five competency headings that serve as preparation topics. They are unweighted and do not establish an official domain count or exhaustive coverage, but each one is framed the same way: understanding and executing successful remediation in the indoor environment. Each competency addresses engineering controls, cleaning and removal methods, worker safety and applicable regulations. The deeper breakdown is in CIES Exam Domains 2026: Complete Guide to All 5 Content Areas; here is how each area connects to scoring.

Reference caveat: ACAC's handbook describes mercury material differently in its body-of-knowledge and study-guide sections, citing EPA Region 5 in one place and the National Elemental Mercury Response Guidebook in another. If mercury shows up in your preparation, read both. The public study guide also warns that its selected pages are examples, not exhaustive coverage, and advises comprehensive study of the references. For a structured way to work through them, see CIES Study Guide 2026: How to Pass on Your First Attempt.

Exam-Day Mechanics That Affect Your Score

The cut score is only half the story. A few delivery details influence how you convert knowledge into correct answers.

Delivery and Question Presentation

The exam is delivered through Kryterion, Inc. in either a proctored testing center or online with video proctoring. The handbook describes a fixed question set with randomized item and answer order, and adaptive testing is not described. In practice, that means two candidates can see the same items in a different sequence, and you should not expect the exam to get harder or easier based on your answers. Calculator permission could not be verified, so do not assume one will be available; practice calculations by hand.

Logistics That Can Cost You Time

• Arrival time: ACAC's current examinations page gives 15 minutes early, while the handbook says 30. Plan for the longer window to be safe.
• Identification: Two government-issued IDs, including one photo ID, are required at the center.
• Online testing: You supply the computer, an approved webcam and a private location. ACAC specifies at least 2 Mbps upload and download, and phones and tablets are excluded.

Pacing the Three Hours

Three hours for 120 questions averages 90 seconds per item. Scenario-heavy remediation questions can run longer than recall questions, so a sound approach is a first pass that answers everything you can resolve quickly, a flag for the rest, and a final pass for flagged items. Since there is no published penalty for guessing, never leave an item blank.

Getting Your Result

Scores are available electronically immediately after you finish and are confirmed by email. You will know your outcome before you leave, which is helpful but also means you should be mentally prepared for either result. Scheduling windows are covered in CIES Exam Dates 2026: Testing Windows, Deadlines & Scheduling.

Passing the Exam vs. Earning the Certification

A passing score is necessary but not sufficient. The CIES credential also requires an approved application. Candidates must meet one of three experience pathways:

• A related four-year postsecondary degree or 30 qualifying college credits plus four years of documented indoor environmental remediation experience
• A related two-year degree or 15 qualifying credits plus six years
• A high school diploma or GED plus eight years

Experience must cover at least three of five areas: asbestos, lead, hazardous materials, microbial/allergens, and industrial hygiene/chemicals/toxicology. Applicants submit four project sheets, each describing the problem, the applicant's own responsibilities and actions, and the outcome, along with educational evidence where applicable and experience verification. ACAC's current application page describes online submission, a six-month window that includes the examination, and unanimous board approval, with the board meeting every four to six weeks. The handbook instead gives 90 days and describes notarized forms and employer affidavits. That conflict is unresolved publicly, so confirm the current rules directly with ACAC before you build a timeline.

If You Miss the Mark: Retake Math

The published fee schedule makes the financial downside of a miss manageable. The examination fee is $100, and the certification fee is $400, which includes a $100 nonrefundable processing fee, for $500 total over the initial two-year term. A retake costs $100. No separate member and non-member schedule is published. The itemized view, including renewal at $400, is in CIES Certification Cost 2026: Complete Pricing Breakdown.

If you do not pass, use the experience to your advantage: write down every topic that felt unfamiliar immediately after the exam, while it is fresh, and rebuild your plan around those gaps. Because the standard is a fixed 75% rather than a curve, a retake is a genuine second chance to demonstrate competence.

Sequencing Prep Around a Hard Cutoff

Since the passing standard is a single overall threshold with no visible domain weights, schedule your preparation to give every competency area real attention, putting the regulation-dense topics earliest while you have the most time to revisit them. ACAC does not develop or administer preparation courses, and no mandatory training hours are published, so the structure is up to you. A condensed example:

Original, reference-explained practice questions are the best way to confirm you are clearing the bar. You can start with the question sets on the CIES practice test site and use the explanations to trace each answer back to a specific regulation. When you want to work through additional scenarios by competency, return to the main practice platform and track your percentage correct against that 75% line.

Frequently Asked Questions