- Identity Check: What This Cheat Sheet Covers
- Exam Format and Scoring at a Glance
- Fees, Eligibility, and Renewal Numbers
- The Seven Competency Statements
- The Three Reference Pillars
- Science Quick-Reference: Psychrometry and Materials
- Drying Strategies and Equipment
- Safety and Regulatory Checklist
- Project Phases and Validation
- Name Confusions to Avoid
- Mapping the Cheat Sheet to a Study Order
- Frequently Asked Questions
- The exam is 120 multiple-choice questions in three hours, closed book, with a 75% passing score.
- Initial cost is $500 total: $100 examination plus $400 certification. Retakes are $100; renewal is $400.
- Certification lasts two years and renewal requires 40 credits: 10 for field activity plus 30 professional-development hours.
- Study the entire ANSI/IICRC S500-2021 text; the study guide warns against limiting prep to highlighted sections.
Identity Check: What This Cheat Sheet Covers
This page condenses the must-know facts for the Council-certified Structural Drying Remediator credential issued by the American Council for Accredited Certification (ACAC). The acronym CSDR is shared by several unrelated credentials in other fields, so whenever you search, qualify it with "ACAC" or the full credential name. Everything below applies only to the ACAC structural drying program.
A one-page review is a memory aid, not a substitute for the source material. If you are still deciding whether the credential suits you, start with What Is CSDR Certification?; if you are ready to build a plan, the full CSDR Study Guide 2026 goes deeper than a cheat sheet can.
Exam Format and Scoring at a Glance
| Item | What to Know |
|---|---|
| Question count | 120 multiple-choice questions |
| Time limit | Three hours (the written exam duration) |
| Answer choices | At least four per question |
| Open or closed book | Closed book |
| Passing score | 75%, set using the Modified Angoff Method |
| Ordering | Question and answer order randomized |
| Results | Immediate electronic results plus an emailed copy |
| Testing provider | Kryterion, Inc., at authorized centers or via secure online video proctoring |
Three details deserve emphasis. First, the Modified Angoff Method means the cut score reflects expert judgment about what a minimally qualified remediator should know, not a curve against other candidates. Second, because answer order is randomized, memorizing "the answer is C" is useless; you must recognize correct content. Third, the three-hour limit applies to the written exam only. It is not a course length or a practical assessment.
For a deeper look at the cut score, see CSDR Passing Score 2026. For realistic expectations about difficulty, read How Hard Is the CSDR Exam?
Fees, Eligibility, and Renewal Numbers
Cost Summary
| Fee | Amount (USD) |
|---|---|
| Examination | $100 |
| Certification | $400 |
| Total initial cost | $500 |
| Retake | $100 |
| Renewal | $400 |
The itemized breakdown, including what is and is not included, lives in CSDR Certification Cost 2026. Confirm current amounts on the ACAC Fees and Payments page before paying, since fee schedules can change.
Eligibility Paths
- Path 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.
- Path B: a high-school diploma or GED plus at least two documented years of structural drying experience.
Application materials include four project sheets, educational records when applicable, employer or experience verification, and then application review and certification-board approval. Preparatory training is not mandatory, so a course is optional rather than a prerequisite. Passing an examination solely for state licensing does not confer this credential. The complete qualification walkthrough is in CSDR Requirements 2026.
Renewal Snapshot
- Certification term: two years.
- Required recertification credits: 40.
- Breakdown: 10 credits for continued field activity plus 30 professional-development hours.
- Also required: audit records and the required current photo.
Plan the 30 professional-development hours across the two-year term rather than in the final month, and keep documentation as you go.
The Seven Competency Statements
The public CSDR candidate handbook prints seven competency and preparation statements, including an umbrella statement. They are unweighted source statements. They are not seven independent, exhaustive official exam domains, and the official examination-content chart could not be retrieved, so no weights are asserted here. For a fuller walkthrough, see CSDR Exam Domains 2026: Complete Guide to All 7 Content Areas.
Domain 1: Code of Conduct
A certificant understands and abides by the ACAC Code of Conduct.
- The Code of Conduct is also required reading in the study guide.
- Expect ethics and professional-responsibility reasoning, not just memorized rules.
Domain 2: Guidelines, Regulations and Standards
Understanding guidelines, regulations and standards relevant to the structural drying industry.
- OSHA general duty clause
- PPE, emergency and fire plans
- Confined spaces and hazardous atmospheres or materials
- Walking and working surfaces; ladders, scaffolding and warnings
Domain 3: Principles, Strategies and Equipment
Applying knowledge of principles, strategies and equipment to the design and execution of structural drying projects.
- Connects science to practical decisions on the job site.
Domain 4: Psychrometry and Hygroscopic Materials
Basic principles of psychrometry and hygroscopic materials.
- Temperature, humidity, vapor pressure and heat
- Psychrometric charts and water phases
- Wood, equilibrium moisture content and cementitious materials
Domain 5: Scientific Principles in Drying Strategy
Correctly applying scientific principles in designing effective drying strategies.
- Dalton's evaporation formula
- Open, closed and combination drying strategies
Domain 6: Equipment Selection and Operation
Selecting and operating appropriate drying equipment.
- Water-class-appropriate equipment
- Air movers, dehumidifiers, portable heating and cooling
- HVAC and ductwork; dehumidification formulas
Domain 7: Project Phases
Designing and executing the phases of a structural drying project, including planning, documentation, drying procedures, HVAC and microbial considerations, and drying validation.
- Source-wording caveat: the handbook's CSDR section words this statement as "A CSDS correctly designs and executes..." even though the preamble also incorrectly says Supervisor. This is the handbook's own inconsistency inside the CSDR section, not a sign that you should follow the separate CSDS pathway or its eligibility rules.
The Three Reference Pillars
The CSDR study guide organizes preparation around three references. These are unweighted preparation categories, not a three-domain blueprint and not exhaustive exam coverage.
| Reference | Reading Instruction |
|---|---|
| IICRC, ANSI/IICRC S500-2021 (fifth edition) | Study the entire text |
| Larsen, et al., Leadership in Restorative Drying, 4th edition (2014) | Selected reading locations specified by the study guide |
| NIOSH, Respirator Selection Logic (2004) | Selected reading locations specified by the study guide |
Also required reading: the ACAC Code of Conduct. These are reference editions, not a numbered 2026 exam version. The study guide specifically warns against limiting your study to highlighted material, which is why cramming only the "flagged" pages is a weak strategy. Note too that the public handbook is free to read, but the reference books themselves are paid purchases.
Key Takeaway
Treat the S500 as your primary text and read it cover to cover. Use Larsen and NIOSH for the specific locations the study guide names, then test yourself on applying, not just recalling, the material.
Science Quick-Reference: Psychrometry and Materials
The science-heavy portions are where many candidates feel the steepest learning curve. Know the concepts well enough to reason through unfamiliar scenarios, not just recite definitions.
Concepts to Be Able to Explain in Your Own Words
- Temperature versus humidity: how air temperature changes its capacity to hold moisture, and why the same moisture content reads as different relative humidity at different temperatures.
- Vapor pressure: the driving force behind moisture movement from wet materials into air, and why a vapor pressure differential matters for drying.
- Water phases: liquid, vapor and the transitions between them, and the heat involved.
- Psychrometric charts: locating a condition from two known properties, then reading additional properties from the chart.
- Equilibrium moisture content: why hygroscopic materials such as wood settle at a moisture level determined by surrounding air conditions.
- Cementitious materials: why drying behavior differs from wood and how moisture is held and released.
Practice reading a psychrometric chart until the process is automatic: find the point, trace the lines, and interpret what moving the point means physically (adding heat, removing moisture, or both). Worked chart problems are far more valuable than rereading definitions.
Drying Strategies and Equipment
Drying Strategy Comparison
| Strategy | Core Idea | Scenario Thinking |
|---|---|---|
| Open | Moisture-laden air exchanges with conditions outside the work area | Consider when outside conditions favor drying and containment is not required |
| Closed | The work area is contained and conditioned independently | Consider when you must control the drying environment tightly |
| Combination | Elements of both, applied to different zones or phases | Consider when a single approach cannot fit the whole structure |
The exam style rewards matching a strategy to a described scenario and justifying why, so rehearse the reasoning behind each choice rather than the labels alone. Dalton's evaporation formula sits underneath this logic: evaporation rate responds to factors such as vapor pressure difference and air movement, and understanding those relationships helps you predict what a given equipment change will do.
Equipment Checklist
- Air movers: understand their role in moving air across wet surfaces and how placement affects evaporation.
- Dehumidifiers: understand how they remove moisture from air and how to apply the dehumidification formulas for capacity reasoning.
- Portable heating and cooling: understand when added heat helps evaporation and when it does not.
- HVAC and ductwork: understand both their potential to assist drying and their risk as pathways for contamination or moisture distribution.
- Water class: equipment selection should be appropriate to the water class, so be ready to connect a scenario's class to sensible equipment choices.
Safety and Regulatory Checklist
Do not treat the safety material as filler. It is explicitly part of the published supporting topics.
- OSHA general duty clause: the employer's broad obligation to provide a workplace free from recognized hazards.
- Personal protective equipment, including the logic of respirator selection from the NIOSH reference.
- Emergency and fire plans.
- Confined spaces and hazardous atmospheres or materials.
- Walking and working surfaces, plus ladders, scaffolding and warnings.
Project Phases and Validation
The last statement covers the lifecycle of a structural drying project. Think of it as a sequence you should be able to narrate from first call to final sign-off:
- Project planning: assess conditions, classify the situation, choose a strategy, and decide on equipment and safety measures.
- Documentation: record conditions, decisions and readings so the work can be defended and reviewed.
- Drying procedures: execute the plan and adjust as measurements change.
- HVAC and microbial considerations: account for how building systems and potential microbial growth affect the approach.
- Drying validation: demonstrate that materials have reached appropriate dry standards before closing out.
Documentation deserves special attention for a second reason: your application itself requires four project sheets, so building good habits in the field helps both your eligibility paperwork and your exam readiness.
Name Confusions to Avoid
| Term | What It Means Here |
|---|---|
| CSDR | Council-certified Structural Drying Remediator (this credential, issued by ACAC) |
| CSDS | Council-certified Structural Drying Supervisor, a separate designation; do not substitute it for CSDR |
| CRSD | A different, similar-looking acronym; not interchangeable with CSDR |
| IICRC ASD | A separate credential from a different organization; compare it deliberately rather than assuming overlap |
The handbook's CSDR section contains stray references to Supervisor and CSDS, as noted under Domain 7. Treat those as source-document inconsistencies. Always confirm the exact credential name and requirements on the official ACAC structural drying pages before applying. For naming basics, see What Does CSDR Stand For? and CSDR Meaning.
Mapping the Cheat Sheet to a Study Order
This is the one place for a schedule, and it follows the logic of the content rather than a generic template: foundations first, science before strategy, strategy before equipment, and everything into scenarios at the end. Adjust the length to your experience.
Foundations and Safety
- Read the ACAC Code of Conduct and the handbook sections.
- Begin the S500 from the start and cover safety and regulatory topics.
- Read the NIOSH respirator selection logic locations named in the study guide.
Psychrometry and Materials
- Work psychrometric chart problems daily.
- Study vapor pressure, water phases, equilibrium moisture content, wood and cementitious materials.
Strategy and Equipment
- Study Dalton's evaporation formula and open, closed and combination strategies.
- Match equipment to water class; practice dehumidification calculations.
- Read the selected Larsen locations.
Project Phases and Timed Practice
- Walk through planning, documentation, procedures, HVAC and microbial issues, and validation.
- Take timed sets of questions at exam pace: 120 questions in three hours.
When you reach the timed stage, work through the CSDR practice test to check pacing and find weak areas, then return to the source text for anything you miss. Candidates comparing options can also review the broader picture in CSDR Pass Rate 2026: What the Data Shows, which explains why no numerical pass ratio should be assumed from the available data.
Frequently Asked Questions
The exam has 120 multiple-choice questions with a three-hour limit. It is closed book, each question has at least four answer choices, and question and answer order is randomized. You receive results immediately by electronic display and by email.
The passing score is 75%, established using the Modified Angoff Method, which reflects expert judgment about minimum competence rather than a comparison against other candidates. See the passing score guide for more detail.
The initial total is $500: a $100 examination fee plus a $400 certification fee. A retake costs $100 and renewal costs $400. Confirm current amounts with ACAC before paying, since schedules can change.
No. One path uses a qualifying two-year degree (or equivalent 15 credit hours in a related scientific field) plus one documented year of structural drying projects. The other uses a high-school diploma or GED plus two documented years of experience. Four project sheets and employer verification are required either way, and training courses are not mandatory.
Certification lasts two years. Current renewal procedures require 40 recertification credits: 10 for continued field activity and 30 professional-development hours, along with audit records and the required current photo. Check ACAC's recertification procedures page for the latest requirements, and see the worth-it analysis in Is the CSDR Certification Worth It? if you are weighing the ongoing commitment.