CSDR Passing Score 2026: Exactly What You Need to Pass

The Number: 75% on a 120-Question Exam

The Council-certified Structural Drying Remediator (CSDR) credential, issued by the American Council for Accredited Certification (ACAC), uses a passing score of 75%. The examination consists of 120 multiple-choice questions, each with at least four answer choices, delivered over three hours in a closed-book format. Question and answer order is randomized, so you and the candidate beside you will not see the same sequence.

Do the arithmetic early so the target feels concrete. If all 120 questions count equally toward your score, 75% works out to 90 correct answers, which leaves room for 30 misses. That framing assumes every question is scored; if ACAC includes unscored items in a given form, the raw number you need could differ slightly, so use 90 as a planning target and not as a guarantee printed in the handbook. The official figure to remember is the percentage: 75%.

Pacing also falls out of the format. Three hours for 120 questions is 90 seconds per question on average, which is generous for recall items and tight for multi-step psychrometric or drying-formula problems. Banking time on definitions and standards questions pays for the calculation items later.

Why 75%? The Modified Angoff Method

ACAC states that the passing score is set using the Modified Angoff Method. In general terms, this is a standard-setting procedure in which subject-matter experts review each question and judge how a minimally qualified candidate would perform on it. Those judgments are aggregated into a defensible cut score tied to the competence the credential is meant to certify.

What this means for you:

• You are not graded on a curve. Your result depends on your own performance against the standard, not on how other candidates did that day.
• The bar reflects competence, not scarcity. A cut score built from expert judgment about minimal qualification is not designed to pass or fail a target share of people.
• Difficult questions are expected. Angoff-style panels deliberately account for harder items, so meeting 75% overall does not require perfection on the hardest calculations.

Note what ACAC does not tell candidates: it does not publish a per-question scoring key, a per-domain minimum, or a numerical 2025 pass ratio for CSDR. Plan against the overall 75% and against the breadth of the study guide, not against rumored sub-scores.

What 75% Looks Like in Practice

A 75% threshold on a technical, standards-driven exam is more demanding than it sounds. Multiple-choice distractors in this field are usually plausible: wrong answers are often correct statements applied to the wrong water class, the wrong drying strategy, or the wrong respirator situation. Guessing your way to 75% is unrealistic; recognizing which condition a scenario describes is what earns points.

If you want a sense of how this feels relative to other credentials, the CSDR difficulty guide breaks down what makes the question style demanding, and the CSDR pass rate analysis explains why no trustworthy percentage exists to compare against.

Passing Score Is Only One Gate

Clearing 75% does not by itself make you a Council-certified Structural Drying Remediator. Certification requires application review and certification-board approval, plus documentation. Specifically:

• Experience pathway A: a qualifying two-year postsecondary degree, or an equivalent 15 credit hours in engineering, science, architecture, industrial hygiene or a related scientific field, plus at least one documented year conducting structural drying projects.
• Experience pathway B: a high-school diploma or GED plus at least two documented years of structural drying experience.
• Documentation: four project sheets, educational records when applicable, and employer or experience verification.

Preparatory training is not mandatory, and passing an examination solely for state licensing does not confer the credential. The full eligibility walkthrough is in CSDR requirements. The application timing detail deserves care: the current online application allows six months, while the handbook retains 90-day and notarized-paper wording. Follow the current application instructions at ACAC and confirm the operative deadline with ACAC before you schedule. Scheduling windows are covered in CSDR exam dates.

Where Your Points Come From: Mapping the Seven Competency Lines

The CSDR section of the ACAC handbook prints seven competency and preparation statements. They are unweighted source statements, not seven independent, exhaustive exam domains with published percentages. ACAC's linked examination-content chart could not be retrieved, so no weights are asserted here. Because you cannot target a weighted blueprint, a 75% result demands breadth: weak coverage of any one area costs points you cannot easily recover elsewhere. The full breakdown is in the CSDR exam domains guide; here is how each line translates into score-relevant preparation.

The Three Reference Books Behind the Questions

The CSDR study guide organizes preparation around three references. These are unweighted preparation categories, not a three-domain blueprint and not exhaustive exam coverage:

1. ANSI/IICRC S500-2021 (fifth edition): the study guide specifies the entire text.
2. Larsen, et al., Leadership in Restorative Drying, 4th edition (2014): selected reading locations are specified.
3. NIOSH, Respirator Selection Logic (2004): selected reading locations are specified.

The guide warns against limiting study to highlighted material. That warning matters for scoring: if you read only the flagged sections, you leave yourself exposed on items drawn from the remainder of the S500. These are reference editions, not a numbered 2026 exam version. This site has reviewed the public handbook, not the paid reference books, so verify current editions with ACAC. For a structured reading order, use the CSDR study guide.

Exam-Day Mechanics That Affect Your Score

The exam is delivered by Kryterion, Inc., either at authorized testing centers or through secure online video proctoring. Both formats are closed book. A few practical points protect your score:

• Randomized order means no domain grouping. A respirator question may sit next to an evaporation-formula question. Reset mentally between items.
• Immediate results. You get an electronic result right away and an emailed copy, so there is no waiting period to endure or to plan around.
• Three hours is the written exam limit. It is not a practical assessment or course-hour figure.
• Online proctoring raises logistics risk. If you choose it, test your environment and connection well beforehand so technical friction doesn't cost focus.

Because there is no penalty structure described for wrong answers in the facts ACAC publishes, answer every question rather than leaving blanks, and flag uncertain items for a second pass if the interface supports it.

If You Miss 75%: Retake Logistics and Costs

Fees in USD: $100 examination plus $400 certification, totaling $500 initially; $100 for a retake; $400 for renewal. A miss therefore costs a retake fee, not a repeat of the full initial total, according to the published fee structure. Confirm the exact retake rules and any waiting periods on ACAC's Examinations and Fees pages, since this article does not assert a retake waiting period. The complete pricing breakdown is in CSDR certification cost.

If your immediate result shows a fail, convert the day into data: write down every topic you remember struggling with while it is fresh, then rebuild your plan around the supporting-topic list above rather than around general review.

Once certified, the credential lasts two years. Current renewal procedures require 40 recertification credits, comprising 10 for continued field activity plus 30 professional-development hours, along with audit records and the required current photo. See CSDR certification for the longer-term picture.

A Score-Driven Study Sequence

This is the one planning section in the article, and it is built around the exam's content rather than a generic calendar. The logic: put the calculation-heavy, foundational science first because everything else depends on it, then layer strategy, equipment and safety, and finish with project process and conduct.

Score yourself on timed practice against the 75% line, and treat anything under it as a signal to revisit the weakest content area, not to take more tests. You can run realistic timed sets on the CSDR practice test site, and the CSDR cheat sheet is a useful last-week review of must-know facts.

Passing-Score Myths to Drop

• "There's a published pass rate I can calculate from." ACAC's Accredited Certification Activity record (December 31, 2025) shows one current CSDR certification and no numerical 2025 CSDR pass ratio. A dash in that report is not a zero-percent pass rate. Any specific percentage you see elsewhere is unsupported.
• "Some domains are worth more, so I can skip the rest." No weights are published for the seven statements, so skipping is a gamble against a 75% bar.
• "Third-party question banks tell me what's on the exam." Listings on sites such as Docsity, StudyGuides.com, Stuvia and Certsarea do not establish question-bank authenticity or answer accuracy. ACAC also publishes an independent preparation-course policy; check it before paying for outside materials.
• "A higher score earns a better credential." Pass is pass. The credential does not record your percentage. For what the credential may mean for your career, see the CSDR ROI analysis, and note that the small, dated certified population means no pay premium or guaranteed demand should be assumed.

For context on the credential's reach, the overview of what CSDR is and the CSDR jobs page cover where it fits in structural drying work, and the CSDR training page covers preparation options, remembering that training is not mandatory.

Frequently Asked Questions