- What a CFST Actually Is
- What a CFST Does on a Loss
- Who Issues the Credential
- The Exam: Format and Question Style
- The Five Exam Domains
- Eligibility and the Application
- Fees and Registration Mechanics
- What the Published Pass Ratio Means
- Who Hires a CFST
- Sequencing Your Preparation by Domain
- Keeping the Credential Current
- Frequently Asked Questions
- A CFST is a Council-certified Fire and Smoke Damage Technician, credentialed by the American Council for Accredited Certification (ACAC).
- The exam has 120 multiple-choice questions, a 3-hour limit, closed-book format, and a 75% passing score.
- Five domains are tested: General Knowledge, Site Characterization, Sample Collection, Analysis/Reporting, and Remediation.
- Applicants need documented fire/smoke investigation experience, four project sheets, and unanimous board approval.
What a CFST Actually Is
A CFST is a Council-certified Fire and Smoke Damage Technician. The credential is awarded by the American Council for Accredited Certification (ACAC) to professionals who investigate and respond to the damage left behind by combustion products: soot, char, ash, smoke residue, and the odors and contamination that travel through a structure after a fire.
The acronym is shared by other, unrelated credentials in other industries, so it is worth being precise. This article covers only the ACAC fire and smoke damage credential. If you are searching for the broader picture, our related explainers on what CFST is and what CFST stands for cover the naming in more depth.
The "technician" title is a little misleading. The credential is not an entry-level, hands-on-only designation. ACAC expects applicants to have designed, conducted, or reported on real investigations of combustion-product damage, and to demonstrate it through documented project work. It is better understood as a recognition of investigative competence than a certificate of course attendance.
What a CFST Does on a Loss
After a fire, the visible damage is only part of the story. Smoke and soot migrate through HVAC systems, wall cavities, attics, and contents far from the burn area. A CFST's job is to characterize that contamination, decide what needs to be sampled, interpret what the data shows, and define what remediation is appropriate.
In practice, that work follows the same arc the exam is built around:
- Understanding the fire event and how combustion products behave once released.
- Walking the site to map where residues have traveled and what surfaces and materials are affected.
- Collecting samples in a way that is defensible and representative.
- Analyzing results and writing the report so that insurers, owners, and contractors can act on it.
- Specifying remediation that actually addresses the contamination found.
Who Issues the Credential
ACAC administers the certification and sets its standards, including the examination, application review, and recertification rules. Exam delivery is handled by a separate testing provider, Kryterion, which offers computer-based testing at testing centers or through online video proctoring. Electronic scores are available immediately after you finish.
One distinction trips people up: passing the exam for state licensing purposes alone does not confer the CFST designation. The designation requires the full application, project documentation, and board approval, not just a passing score. If you are weighing the credential against other options, our overview of CFST certification and ROI analysis walk through that decision.
The Exam: Format and Question Style
The CFST exam is a closed-book, written examination delivered by computer. The format facts are straightforward:
| Exam Feature | Detail |
|---|---|
| Number of questions | 120 multiple-choice items |
| Answer choices | At least four per question |
| Time allowed | 3 hours |
| Reference materials | None (closed-book) |
| Passing score | 75%, set using the modified Angoff method |
| Delivery | Testing center or online video proctoring (Kryterion) |
| Score reporting | Electronic, available immediately |
| ID at testing centers | Two government-issued IDs, including one photo ID |
The 75% cut score comes from the modified Angoff method, a standard-setting process in which subject-matter experts judge how a minimally competent candidate would perform on each item. That means the threshold reflects a competence judgment rather than a curve against other test-takers. For the arithmetic of what that requires on a 120-item exam, see our guide to the CFST passing score.
Because the exam is closed-book and multiple-choice, expect questions that test applied judgment: choosing the correct sampling approach for a described scenario, recognizing what a result implies, or identifying the right remediation step. Memorizing definitions alone will not carry you. Questions reward people who have actually thought through a loss from walkthrough to cleanup.
The Five Exam Domains
ACAC publishes the exam content as five domains (in its chart approved March 20, 2024). The retrieved chart and handbook do not publish percentage weights for these domains, so any claim about how many questions come from each is guesswork. Study all five. For a full walkthrough, see our complete guide to all five CFST content areas.
Domain 1: General Knowledge
The foundation: how fires produce smoke and residues, the terminology used across the field, and the basic principles that every later domain builds on.
- Combustion products and how they differ by fuel and burn conditions
- Core vocabulary and concepts used in fire and smoke investigations
- The professional context in which CFSTs operate
Domain 2: Site Characterization
Reading a fire-affected property: understanding where contamination went and why, before a single sample is taken.
- Assessing the extent and pattern of smoke and soot migration
- Evaluating building materials, contents, and systems affected
- Planning an investigation around what the site tells you
Domain 3: Sample Collection
Gathering evidence that holds up. Poor sampling undermines every conclusion that follows.
- Selecting appropriate sampling methods for the question being asked
- Choosing representative locations and avoiding cross-contamination
- Documenting and handling samples properly
Domain 4: Sample Analysis, Data Interpretation & Report Writing
Turning raw results into conclusions and communicating them clearly.
- Understanding what analytical results do and do not show
- Interpreting data in the context of the site and the loss
- Writing reports that are clear, supportable, and actionable
Domain 5: Remediation
Deciding what has to be done to restore the property, and verifying that it worked.
- Matching cleaning and removal methods to the contamination found
- Setting remediation objectives and confirming they were met
- Understanding the limits of what cleaning can achieve
Eligibility and the Application
This is where the CFST differs most from certifications you can earn by simply passing a test. ACAC requires documented experience, and the board reviews your application before the credential is granted.
Education and experience pathways
- Pathway one: a qualifying science-related two-year degree (or a 15-credit equivalent) plus one year of documented fire/smoke investigation experience.
- Pathway two: a high-school diploma or GED plus two years of documented experience.
The experience has to be in investigations of combustion-product damage. Water-damage, microbial-growth, asbestos, lead, and other indoor environmental investigations do not qualify, however extensive your background in them.
What you submit
- The official CFST application
- Four project sheets documenting your investigation work
- Applicable education transcripts
- Required email verifications
Certification requires unanimous board approval, so the project sheets matter as much as the exam. For the complete breakdown, see our CFST requirements guide.
Fees and Registration Mechanics
The fee structure is split between an examination fee and a certification fee:
| Fee Item | Amount (USD) |
|---|---|
| Examination fee | $100 |
| Certification fee | $400 |
| First two-year term total (US/Canada) | $500 |
| First two-year term total (outside US/Canada) | $525 |
| Retake | $100 |
No training course is mandatory, so the exam and certification fees are the required costs. Courses and prep materials are optional. For the full picture, including renewal, read our CFST certification cost breakdown. The current application and project-sheet instructions are published by ACAC, so always work from the latest version.
What the Published Pass Ratio Means
ACAC's 2025 Exam Pass Ratio reports 66%, with 10 passing out of 15 examinations. Read that carefully before drawing conclusions from it:
- It includes retakes, so repeat attempts are counted alongside first attempts.
- It includes state-licensing-only examinations, not just CFST candidates seeking the designation.
- With only 15 examinations in the sample, a single result moves the percentage substantially.
In short, 66% is the issuer's printed figure, but it is not a first-attempt pass rate and should not be treated as one. Our pass rate analysis and difficulty guide explore how to interpret it responsibly.
Who Hires a CFST
The credential is aimed at people whose work depends on credible fire and smoke damage assessment. That generally includes:
- Restoration and remediation firms that need personnel qualified to characterize and scope smoke-damage losses.
- Consulting and environmental firms that perform independent investigations and write reports for clients.
- Insurance-adjacent roles where assessors and consultants evaluate the extent of a loss and the reasonableness of the proposed response.
- Independent consultants who use the credential to demonstrate competence to property owners and attorneys.
Because the credential signals investigative and reporting skill, it tends to be most valuable where your work product is a report that others rely on. We do not publish earnings figures here, since no verified numbers are available in ACAC's materials; see our salary guide and CFST jobs overview for qualitative context.
Sequencing Your Preparation by Domain
ACAC points candidates to its Council-certified Fire and Smoke Damage (CFSx) Certification Program Exam Study/Review Guide (Rev. 12-2024) as a preparation source. Whatever resources you use, order your study to follow the logic of a real project so each domain reinforces the next. For a fuller plan, see our CFST study guide.
Domain 1: General Knowledge
- Lock down terminology and combustion-product concepts first, since every later domain assumes them
Domain 2: Site Characterization
- Practice reasoning from a described fire scenario to likely contamination patterns
Domain 3: Sample Collection
- Work through which method fits which question, and where sampling errors originate
Domain 4: Analysis, Interpretation & Reporting
- Practice reading results in context and judging what conclusions they actually support
Domain 5: Remediation, then full review
- Tie remediation choices back to sampling and interpretation, then take timed mixed-domain practice sets
Since the exam is 120 questions in 3 hours, you have roughly a minute and a half per item. Timed practice in the final week matters. You can drill that format with the CFST practice tests, and our one-page cheat sheet is useful for last-pass review.
Keeping the Credential Current
The CFST is valid for two years. Renewal requires:
- $400 renewal fee
- 40 recertification credits, made up of 10 credits for attesting to continued field activity plus 30 hours of professional development
- Retained documentation, since your records can be audited
Key Takeaway
Keep a running log of continuing education and field activity from day one of your term. Audits ask for proof, and reconstructing 30 hours of professional development after the fact is far harder than recording it as you go. Recertification procedures are published by ACAC.
Frequently Asked Questions
It stands for Council-certified Fire and Smoke Damage Technician, a credential issued by the American Council for Accredited Certification (ACAC). See also what CFST means.
The exam has 120 multiple-choice questions with at least four answer choices each, a 3-hour time limit, and a closed-book format. The passing score is 75%.
No. ACAC does not mandate any training course. Eligibility is based on your education and documented fire/smoke investigation experience, though many candidates still use training and prep resources to prepare.
No. You must also submit the application, four project sheets, transcripts, and email verifications, and receive unanimous board approval. Passing the exam for state licensing alone does not confer the designation.
The first two-year term costs $500 in the US and Canada ($100 exam plus $400 certification) or $525 elsewhere. A retake is $100, and renewal is $400 plus 40 recertification credits.
If you are deciding whether to pursue the credential, start with the eligibility and project-sheet requirements, since those take the longest to assemble, then build your exam preparation around the five domains. When you are ready to test yourself under realistic conditions, the practice exams are a good next step, and our CFST certification explainer offers another angle on the credential.