- How to Read the Seven Content Areas
- Exam Format Behind the Domains
- Domain 1: The ACAC Code of Conduct
- Domain 2: Guidelines, Regulations and Standards
- Domain 3: Principles, Strategies and Equipment
- Domain 4: Psychrometry and Hygroscopic Materials
- Domain 5: Scientific Principles in Drying Strategy
- Domain 6: Selecting and Operating Equipment
- Domain 7: Project Phases (and the CSDS Wording)
- Mapping the Three Reference Sources
- Scheduling the Domains Across Your Prep
- Frequently Asked Questions
- The CSDR handbook prints seven competency statements; they are unweighted, not seven official exam domains with published percentages.
- The exam is 120 multiple-choice questions in three hours, closed book, with a 75% passing score.
- Study the entire ANSI/IICRC S500-2021 text, not just highlighted sections, plus selected Larsen and NIOSH readings.
- Domain 7 says "CSDS" in the source handbook; the credential you are pursuing is still Council-certified Structural Drying Remediator.
How to Read the Seven Content Areas
Before you build a study plan around the Council-certified Structural Drying Remediator (CSDR) credential, you need to understand what the seven "domains" actually are. The American Council for Accredited Certification (ACAC) publishes a CSDR Candidate Handbook with a Required Skills and Exam study guide. Inside it are seven competency and preparation statements, including an umbrella statement about the Code of Conduct. Those seven lines are what this article calls Domains 1 through 7.
That means any resource claiming "Domain 4 is worth 22% of the exam" is inventing a number. For a broader orientation to the credential itself, see What Is CSDR Certification? and, for the naming confusion that trips up many searchers, What Does CSDR Stand For?
Exam Format Behind the Domains
The domains describe what you must know. The format describes how you will be asked. Here is what ACAC specifies for the CSDR examination:
| Element | CSDR Detail |
|---|---|
| Question count | 120 multiple-choice questions |
| Time limit | Three hours (written examination duration) |
| Reference materials | Closed book |
| Answer choices | At least four per question |
| Passing score | 75%, set using the Modified Angoff Method |
| Ordering | Question and answer order randomized |
| Results | Immediate electronic result plus an emailed result |
| Testing provider | Kryterion, Inc., at authorized centers or via secure online video proctoring |
Closed book matters for how you study the domains. Formulas, psychrometric relationships and equipment logic must be internalized rather than looked up. If you want the arithmetic of the cut score, read CSDR Passing Score 2026; for a realistic sense of difficulty, see How Hard Is the CSDR Exam?
Domain 1: The ACAC Code of Conduct
Domain 1 - A certificant understands and abides by the ACAC Code of Conduct.
This is the umbrella statement of the CSDR section, and it is the easiest to underestimate. The ACAC Code of Conduct is required reading alongside the technical references.
- Read the Code of Conduct as a document, not a summary; scenario questions reward knowing what it actually requires.
- Understand how the Code connects to designation use, since the handbook's designation-use section establishes "Remediator" as the correct name for the credential.
- Expect professional-conduct judgment calls rather than formulas.
Many technically strong candidates skip this domain because it feels soft. Because it is an explicit, named statement in the handbook, treat it as examinable and give it a dedicated reading session.
Domain 2: Guidelines, Regulations and Standards
Domain 2 - A certificant understands guidelines, regulations and standards relevant to the structural drying industry.
The handbook's published supporting topics for this area center on worksite safety and regulatory duties:
- The OSHA general duty clause
- Personal protective equipment (PPE)
- Emergency and fire plans
- Confined spaces
- Hazardous atmospheres and hazardous materials
- Walking and working surfaces, plus ladders, scaffolding and warnings
This is where the NIOSH Respirator Selection Logic (2004) reading earns its place. Respirator selection is a structured decision process, and the exam is closed book, so practice walking through the logic rather than memorizing a chart. Pair it with the safety chapters of ANSI/IICRC S500-2021.
Domain 3: Principles, Strategies and Equipment
Domain 3 - A certificant applies knowledge of principles, strategies and equipment to the design and execution of structural drying projects.
The handbook's statement for this area is introductory ("In particular:"), so it frames the more specific science and equipment statements that follow. Supporting topics published for the CSDR section include:
- Open, closed and combination drying strategies
- Water-class-appropriate equipment selection
- The relationship between planning, documentation and drying procedures
Think of Domain 3 as the "application" layer. Domains 4 and 5 supply the science; Domain 6 supplies the equipment detail; Domain 3 asks you to combine them into a defensible plan. Questions here tend to present a loss and ask for the best strategic choice. A candidate who has only memorized definitions will struggle; one who has reasoned through open versus closed versus combination approaches for different structures will not.
Domain 4: Psychrometry and Hygroscopic Materials
Domain 4 - The certificant understands the basic principles of psychrometry and hygroscopic materials.
The published supporting topics are the heart of the science foundation:
- Temperature, humidity and vapor pressure
- Heat and the behavior of water phases
- Psychrometric charts
- Wood and equilibrium moisture content (EMC)
- Cementitious materials
Because the exam is closed book, you cannot rely on a chart in front of you. The skill to build is directional reasoning: what happens to relative humidity when temperature rises with moisture held constant, why vapor pressure drives moisture movement, and why wood and cementitious materials behave differently as they equilibrate with surrounding air.
Key Takeaway
Practice psychrometric reasoning in both directions. Be able to predict how a change in air conditions affects a material's moisture content, and to explain why a material stops drying once it reaches equilibrium with the room.
Domain 5: Scientific Principles in Drying Strategy
Domain 5 - The certificant correctly applies scientific principles in the design of effective drying strategies.
Where Domain 4 asks you to understand principles, Domain 5 asks you to apply them. The handbook's published supporting topics include:
- Dalton's evaporation formula and what its variables imply for drying
- Open, closed and combination drying strategies
- How vapor pressure differentials and air movement influence evaporation
The practical test of mastery is being able to say which lever to pull. If evaporation is limited by saturated air at the material surface, moving air helps; if the surrounding air cannot accept more moisture, dehumidification becomes the constraint. Knowing which situation you are in is the difference between a good and a poor answer.
For a compact refresher you can use close to test day, see the CSDR Cheat Sheet, and work scenario questions through the CSDR practice test.
Domain 6: Selecting and Operating Equipment
Domain 6 - The certificant selects and operates appropriate drying equipment in the execution of structural drying projects.
The published supporting topics for equipment include:
- Water-class-appropriate equipment
- Air movers
- Dehumidifiers
- Portable heating and cooling
- HVAC and ductwork considerations
- Dehumidification formulas
Equipment questions typically hinge on matching the tool to the condition. A class of water loss implies how much evaporation load exists; the equipment choice should follow from that load and from the drying strategy chosen. Dehumidification formulas are a place where closed-book preparation matters: know the relationships well enough to reason through them without a reference.
Domain 7: Project Phases (and the CSDS Wording)
Domain 7 - "A CSDS correctly designs and executes the phases of a structural drying project."
This is the seventh statement exactly as the source handbook prints it. Published supporting topics include:
- Project planning
- Documentation
- Drying procedures
- HVAC and microbial considerations
- Drying validation
Practically, treat Domain 7 as the end-to-end project lifecycle: plan, document, execute drying procedures, account for HVAC and microbial concerns, and validate that drying is complete. Validation is the capstone; know what evidence demonstrates a structure has reached its drying goal. The documentation habits here also overlap with the project sheets required for your application, which makes real field records useful study material. See CSDR Requirements for eligibility and the four-project documentation expectation.
Mapping the Three Reference Sources
Separate from the seven statements, 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 | Where It Helps Most |
|---|---|
| IICRC, ANSI/IICRC S500-2021 (fifth edition) | Standards, water classes, drying principles, equipment, validation; the study guide specifies the entire text |
| Larsen, et al., Leadership in Restorative Drying, 4th edition (2014) | Drying science and strategy; selected reading locations are specified |
| NIOSH, Respirator Selection Logic (2004) | Respiratory protection decisions tied to the safety and hazardous-atmosphere topics |
Key Takeaway
The study guide warns against limiting your preparation to highlighted material. Read the whole S500 text and the specified Larsen and NIOSH sections. Also note that these are reference editions, not a numbered "2026 exam version."
One practical note: this guide is built from the public handbook, not from the paid reference books themselves, so verify specific page-level coverage against your own copies. For a plan that turns these references into a calendar, read the CSDR Study Guide 2026.
Scheduling the Domains Across Your Prep
The one place sequencing genuinely matters is science before application. Domains 4 and 5 are prerequisites for reasoning well in Domains 3, 6 and 7, so schedule them early. An example arrangement, adjustable to your own timeline:
Domains 1 and 2
- Read the ACAC Code of Conduct in full
- Work through safety topics and the NIOSH respirator logic
Domains 4 and 5
- Psychrometrics, vapor pressure, EMC, cementitious materials
- Dalton's formula and open, closed and combination strategies
Domains 3 and 6
- Equipment by water class, air movers, dehumidifiers, HVAC
- Dehumidification formulas reasoned without a reference
Domain 7 and full review
- Planning, documentation, validation
- Timed practice against the 120-question, three-hour format
Whatever pace you choose, finish with timed practice at the real length. A CSDR practice exam run under three-hour conditions shows you whether your closed-book recall holds up. If you are weighing the investment, compare it against CSDR certification cost and whether the credential is worth it.
Frequently Asked Questions
No weights are asserted. The seven lines are unweighted competency and preparation statements from the handbook, and the official examination-content chart could not be retrieved for this guide. Prepare for all seven and confirm current details with ACAC.
The source handbook's CSDR section contains that wording in its preamble, skills introduction and final statement. CSDS is the Structural Drying Supervisor designation, a different credential. This guide preserves the wording with a caveat and does not use CSDS eligibility for CSDR.
The initial total is $500 USD: $100 for the examination plus $400 for certification. A retake is $100 and renewal is $400. See the pricing breakdown for details.
ACAC's Accredited Certification Activity report (December 31, 2025) records one current CSDR certification and no numerical 2025 pass ratio. A dash in that report should not be read as a zero-percent pass rate. See CSDR Pass Rate 2026 for context.
No. Preparatory training is not mandatory. Eligibility instead rests on education plus documented structural drying experience, four project sheets, and certification-board approval. Review ACAC's independent preparation-course policy if you choose to take a course.
Certification lasts two years. Current renewal procedures require 40 recertification credits: 10 for continued field activity plus 30 professional-development hours, along with audit records and the required current photo. Confirm the operative procedures with ACAC before your renewal window.