- What You Are Actually Studying For
- The Two-Part Exam: Written Test Plus Hands-On Performance
- The Five ASTM Reference Standards
- Sequencing Your Preparation Around the Five Tests
- Fees, Eligibility, and Registration Mechanics
- Passing the Performance Appointment Without Coaching
- Failure, Retake Windows, and Recertification
- Preparation Pitfalls Specific to This Credential
- Where the Credential Fits in the Flooring Trade
- Frequently Asked Questions
- This is the ICRI Concrete Slab Moisture Testing Technician-Grade 1 credential, built on five ASTM test methods.
- You must pass a written exam and perform all five tests before a qualified judge without coaching.
- Eligibility requires approved hands-on testing experience or a prequalification waiver through the Demonstration and Workshop.
- Failed written exams are retaken in full; failed performance methods alone are repeated, within one year.
What You Are Actually Studying For
The Concrete Slab Moisture Testing Technician credential is administered by the International Concrete Repair Institute (ICRI). The exact designation is ICRI Concrete Slab Moisture Testing Technician-Grade 1. If you are new to the acronym, our explainer on what CSMT certification is covers the basics, and the overview of what CSMT stands for clears up the name. This guide assumes you already know you want the credential and need a plan to pass it.
The first thing to understand is that this is not a purely academic exam. It is a hybrid: you demonstrate knowledge on paper and demonstrate skill with your hands. A candidate who can recite every ASTM section number but fumbles a probe installation will not certify, and a veteran installer who has never read the standards closely can stumble on the written portion. Passing on the first attempt means preparing for both halves deliberately.
The Two-Part Exam: Written Test Plus Hands-On Performance
Certification requires two things: passing the ICRI-administered written examination, and successfully performing all five tests before a qualified judge without coaching. The published schedule allocates one hour to the written examination and a separate assigned one-hour performance appointment. The 3-4-hour education session that precedes testing is instructional and is not examination time.
Two details are worth stating plainly because candidates often ask. First, the written question count and numeric passing threshold were not verified in the public program description, so any specific number you see quoted elsewhere should be treated with caution. Our breakdown of the CSMT passing score explains what is and is not known. Second, because the public materials describe format and timing but not the item bank, the best preparation is mastery of the reference standards and the education session rather than memorizing guessed question patterns.
| Component | What It Tests | Format Notes |
|---|---|---|
| Education session | Instruction covering the reference topics; also covered by the exams | 3-4 hours; not examination time |
| Written examination | Knowledge of the five reference standards and education content | One hour scheduled |
| Performance appointment | Performing all five tests correctly before a qualified judge | Separate assigned one-hour slot; no coaching |
For a candid look at the difficulty of each half, see how hard the CSMT exam is.
The Five ASTM Reference Standards
Everything in this credential traces back to five standards. Learn what each one measures, what equipment it requires, and where candidates commonly go wrong. A fuller treatment lives in the complete guide to all five CSMT content areas; here is the study-oriented summary.
Domain 1: ASTM F710 - Preparing Concrete Floors to Receive Resilient Flooring; Section 5.2 pH Testing
This standard covers floor preparation for resilient flooring, and the exam focus here is the pH testing provision in Section 5.2. ICRI lists Section 5.2 exactly this way, so study that specific section rather than the whole document as if every clause were equally likely.
- Understand why surface alkalinity matters to adhesives and flooring performance.
- Know how surface preparation affects the validity of a pH reading.
- Practice the test procedure itself, since you will perform it for the judge.
Domain 2: ASTM F1869 - Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride
The calcium chloride test measures how much moisture vapor leaves the slab surface over a set period. It is a hands-on, kit-based method with weighing, placement, and timing steps that all have to be documented correctly.
- Know the relationship between the dish, the dome, the sealing method, and the exposure period.
- Be precise about weighing and recording; errors compound into the calculated result.
- Understand the environmental conditions that must exist before and during the test.
Domain 3: ASTM F2170 - Determining Relative Humidity in Concrete Floor Slabs Using in situ Probes
Probe-based relative humidity testing measures moisture within the slab rather than at the surface. Expect the most procedural depth here: drilling, sleeve placement, equilibration, and reading.
- Know how hole depth relates to slab thickness and drying conditions.
- Understand equilibration before reading and why rushing it ruins the result.
- Be able to explain what the reading represents compared with a surface test.
Domain 4: ASTM F2659 - Preliminary Evaluation of Comparative Moisture Condition of Concrete, Gypsum Cement and Other Floor Slabs and Screeds Using a Non-Destructive Electronic Moisture Meter
The electronic meter method is a screening tool. The key conceptual point is in the title itself: it is preliminary and comparative, not a substitute for the quantitative methods.
- Know the limits of a non-destructive meter and why it cannot replace F1869 or F2170 results.
- Understand how to survey a slab to identify areas needing further testing.
- Recognize how material type can affect meter readings.
Domain 5: ASTM F3191 - Field Determination of Substrate Water Absorption (Porosity) for Substrates to Receive Resilient Flooring
This standard addresses how readily the substrate absorbs water, which bears on adhesive and coating performance. It is the newest-feeling topic for many experienced installers, so do not assume field familiarity covers it.
- Understand what porosity indicates about surface condition and bond.
- Practice the field procedure so that timing and observation steps become automatic.
Sequencing Your Preparation Around the Five Tests
Because the credential is performance-based, your study plan should front-load the procedures that are hardest to master and pair reading with practice. This is the one place generic scheduling advice is useful, so here it is tied directly to the five standards.
Orientation and the surface tests
- Read the ICRI program page and your registration materials end to end.
- Work through F710 Section 5.2 pH testing and F2659 meter screening, the two quickest methods to get fluent in.
Calcium chloride (F1869)
- Study the full procedure and the calculation of results.
- Rehearse weighing, placement, and documentation until the sequence is automatic.
In situ probes (F2170)
- Spend the most time here; it is the most procedurally dense method.
- Drill the logic of depth, sleeve, equilibration, and reading until you can narrate it unprompted.
Porosity (F3191) and integration
- Learn the water absorption field method.
- Run a full mock sequence of all five tests, then take timed written practice questions.
A one-page CSMT cheat sheet is helpful for last-minute review once you have done the underlying work, and you can test written recall with the practice questions on the main CSMT practice test site.
Fees, Eligibility, and Registration Mechanics
Budget and eligibility are where first-time candidates most often get surprised, so review them before you invest study time. For deeper detail, see the CSMT certification cost breakdown and the guide to CSMT requirements and eligibility.
Eligibility requires one of two paths: ICRI-approved previous hands-on testing experience, or a prequalification waiver earned through participation in the Demonstration and Workshop. If you do not have documented field experience, the workshop route is your way in.
| Candidate Type | Published 2026 Full-Course Fee |
|---|---|
| ICRI member | USD 1,050 |
| Non-member | USD 1,350 |
| Verified student member | USD 510 |
These fees cover the full course, including the education session and the demonstration/workshop. Do the math on membership before registering: the gap between the member and non-member fees is USD 300, which may be worth weighing against the cost of joining.
Scheduling matters too. ICRI hosts program sessions at various sites, such as a November 4-5, 2026 session at Structural Technologies in the Baltimore area, so check the CSMT exam dates and scheduling guide and the ICRI program page for a session near you.
Passing the Performance Appointment Without Coaching
The performance portion is where preparation habits matter most. You perform all five tests before a qualified judge, and the judge does not coach. That means you cannot rely on a prompt, a hint, or a correction mid-test. You must know the sequence, the equipment, and the documentation requirements cold.
Build a mental checklist for each method
For every test, be able to state in order: required conditions, equipment, preparation steps, execution, timing, reading or recording, and cleanup. Say each checklist out loud during practice. If you pause to recall a step in practice, you will pause in front of the judge.
Practice with your own hands, not just your eyes
Watching a demonstration builds recognition, not recall. Use the Demonstration and Workshop as a chance to actually handle the equipment, and if you can arrange access to test kits and probes beforehand, rehearse the physical steps. The calcium chloride dish handling and probe installation are especially unforgiving of unfamiliarity.
Key Takeaway
Treat the performance appointment as a rehearsed routine, not an improvised demonstration. Write a step-by-step checklist for each of the five tests, then practice until you can run each one start to finish without consulting it.
Failure, Retake Windows, and Recertification
Knowing the consequences of a miss helps you plan, even if you intend to pass the first time. The rules are specific and time-bound.
- Initial written exam: if you fail, you must retake it in full.
- Performance methods: if you fail, you repeat only the failed methods, not all five.
- Deadline: the retakes must occur within one year, or you must repeat the full certification course.
Certification lasts five years. First recertification is written-exam-only, at USD 495 for members or USD 595 for non-members. A failed first-recertification written exam has its own separate six-month re-examination deadline before the full course is required. Second and later recertifications require the full certification course, at USD 695 for members or USD 895 for non-members.
If you are weighing whether these ongoing costs justify the credential, the analysis of whether CSMT certification is worth it walks through the tradeoffs.
Preparation Pitfalls Specific to This Credential
Mixing up what each test measures
The five methods overlap in purpose but differ in what they actually measure. F1869 measures vapor emission at the surface, F2170 measures relative humidity within the slab, F2659 is a preliminary comparative screen, F710 Section 5.2 addresses pH, and F3191 addresses water absorption. Candidates who blur these together lose points on conceptual questions.
Treating the meter as a final answer
Because the electronic meter is easy and fast, it is tempting to over-trust it. The standard's own title frames it as preliminary and comparative. Be ready to explain when a meter reading should trigger quantitative testing.
Ignoring the education session
Since the examinations also cover the education session, skipping or skimming it is a mistake. Take notes, ask questions, and treat the session as exam content, not background.
Relying on unverified numbers
Several things remain unverified publicly, including the written question count and numeric passing threshold. If a forum post or third-party site quotes confident figures, treat them skeptically. The CSMT pass rate discussion explains why published pass-rate claims should be handled carefully.
Using outdated source lists
Legacy study lists containing ASTM F2420 and older editions are a real hazard. Always cross-check against the materials supplied at registration.
Where the Credential Fits in the Flooring Trade
Moisture testing is a gatekeeping step in flooring projects: installers, manufacturers, and warranty providers all care whether a slab is dry enough and chemically suitable before flooring goes down. That makes the credential relevant to flooring contractors, testing and inspection firms, concrete and moisture-mitigation specialists, and consultants who document slab conditions. Employers value a technician who can run the standardized tests correctly and defend the results.
For a sense of the roles that look for this credential, see our overview of CSMT jobs, and for compensation context, the CSMT salary guide. We deliberately avoid quoting specific earnings here because the public program information does not support any figure, and you should treat any precise number with skepticism unless it is sourced.
If you want a consolidated walkthrough once you start studying, bookmark our main CSMT study guide and return to the practice test site to check your written recall before exam day.
Frequently Asked Questions
The International Concrete Repair Institute (ICRI) administers it. The exact credential is ICRI Concrete Slab Moisture Testing Technician-Grade 1.
You must pass the ICRI-administered written examination and successfully perform all five tests before a qualified judge without coaching. Eligibility requires approved prior hands-on testing experience or a prequalification waiver through the Demonstration and Workshop.
Published fees including the education session and demonstration/workshop are USD 1,050 for ICRI members, USD 1,350 for non-members, and USD 510 for verified student members.
A failed initial written exam must be retaken in full, while failed performance methods alone are repeated. Retakes must happen within one year, or you must repeat the full certification course.
Certification lasts five years. First recertification is written-exam-only (USD 495 member, USD 595 non-member); second and later recertifications require the full course (USD 695 member, USD 895 non-member).