- Which CEAC This Sheet Covers
- Exam Format at a Glance
- The Six Official Domain Headings
- The Seven Assigned Publications
- Eligibility Paths and Application Mechanics
- Fees, Validity, and Recertification
- Reading the Published Numbers Carefully
- Accreditation: What to Verify
- Sequencing Your Review by Domain
- Frequently Asked Questions
- CEAC here means Council-certified Environmental Allergen Consultant, issued by the American Council for Accredited Certification (ACAC).
- The exam is 120 closed-book multiple-choice questions in 3 hours, with a 75% passing score.
- Six domains are named publicly, but ACAC does not publish percentage weights for them.
- Seven assigned publications form the reading list, and ACAC recommends reading them in full.
Which CEAC This Sheet Covers
Several unrelated credentials share the abbreviation CEAC. This cheat sheet covers only the Council-certified Environmental Allergen Consultant credential from the American Council for Accredited Certification. It is an environmental allergen consulting credential for professionals who investigate allergen conditions in buildings. It has nothing to do with environmental-access credentials that happen to use the same letters.
If you are still orienting yourself, these background reads explain the basics: What Is CEAC?, What Does CEAC Stand For?, and CEAC Certification. This page is the compressed version: the facts worth memorizing or double-checking before you commit time and money.
Exam Format at a Glance
| Item | What ACAC Publishes |
|---|---|
| Certifying body | American Council for Accredited Certification (ACAC) |
| Testing provider | Kryterion, Inc. |
| Question count | 120 multiple-choice questions, each with at least four answer options |
| Time limit | 3 hours |
| Reference materials | Closed book |
| Passing score | 75%, established with the Modified Angoff Method |
| Delivery | Computer-delivered at a test center or via secure online video proctoring |
| Score reporting | Immediate, with email confirmation |
Some arithmetic helps with pacing. Three hours across 120 questions works out to 90 seconds per question on average. Allergen-investigation questions often wrap a scenario around a single decision, such as which sampling approach fits a given complaint, so train yourself to identify the decision point quickly and move on. For the scoring details, see CEAC Passing Score 2026; for scheduling, see CEAC Exam Dates 2026.
The Modified Angoff Method, Briefly
The 75% cut score is not a curve. The Modified Angoff Method has subject-matter experts judge how a minimally competent candidate would perform on each item, and those judgments set the passing standard. Practically, this means the standard reflects defensible professional competence, not a fixed share of test-takers passing. Your job is to be solidly competent across all six domains rather than brilliant in one.
Test-Day Logistics That Conflict
ACAC's pages disagree on test-center arrival time: the candidate handbook says to arrive 30 minutes early, while the general examination page says 15 minutes. Follow the instructions on your actual appointment confirmation, and when in doubt, arrive earlier. Bring the identification your confirmation requires, and if you choose online proctoring, test your equipment and room setup in advance.
The Six Official Domain Headings
The six domain lines below reproduce the official public examination headings from ACAC's study packet. They are not an inferred curriculum. Importantly, percentage weights are not published in the reviewed sources, so any site claiming exact domain weights for this exam is guessing. For a deeper walkthrough of each area, see CEAC Exam Domains 2026: Complete Guide to All 6 Content Areas.
Domain 1: The allergic response in humans
The biological foundation. Expect questions that connect exposure to health outcomes, which is the reason the whole profession exists.
- How sensitization and allergic reactions develop
- How exposure relates to symptoms, including asthma
- Why some occupants react and others do not
Domain 2: Types of allergens and their presence in the built environment
Know what you are looking for and where it lives.
- Major indoor allergen categories and typical sources
- Where allergens accumulate: dust reservoirs, soft furnishings, moisture-affected materials
- How allergens move between indoor and outdoor air
Domain 3: Principles of the Built Environment
Buildings are systems. Allergen problems usually trace back to how a structure handles air, moisture, and materials.
- Ventilation, airflow, and filtration fundamentals
- Moisture sources and building envelope behavior
- How building design and occupant activity shape exposure
Domain 4: Investigation principles, procedures, and equipment
The hands-on core of the credential. This domain is where the assigned sampling and protocol publications matter most.
- Designing an investigation around a defined question
- Air and dust sampling methods, and how to choose between them
- Equipment use, sample handling, and working with laboratories
Domain 5: Allergen evaluation and remediation strategies
Turning findings into decisions and corrective action.
- Interpreting results with appropriate caution about their limits
- Source control, cleaning, and moisture-correction approaches
- Verifying whether a remediation actually worked
Domain 6: Guidelines, regulations, and standards
The framework a consultant works inside. Questions here reward knowing which document speaks to which problem.
- Applicable guidance and standards relevant to allergen investigation
- How federal healthy-housing resources frame allergen and asthma issues
- Where professional judgment applies when no hard threshold exists
The Seven Assigned Publications
ACAC's study packet is shared across the CEAC, CEAI, and CEAT credentials, but a shared reading list does not make their eligibility rules or exams identical. Do not assume content or requirements transfer between those credentials. The seven assigned publications, with the dates ACAC lists, are:
- APHL, Environmental Laboratories and Indoor Air Testing: A Primer (2015)
- CDC, Healthy Housing Reference Manual, chapter 5 (2006)
- EPA, Exposure Factors Handbook, chapter 19 (updated 2018)
- Estelle Levetin, Methods for Aeroallergen Sampling, Current Allergy and Asthma Reports 4:376-383 (2004)
- HHS, Airborne Allergens: Something in the Air (2003)
- HUD, Healthy Homes Issues: Asthma (2012)
- HUD, Vacuum Dust Sample Collection Protocol for Allergens (2008)
Mapping Publications to Domains
ACAC does not publish an official crosswalk, so treat the following as a sensible study aid rather than an official blueprint:
- The HHS airborne allergens publication and HUD's asthma issue brief naturally support the human-response and allergen-type material (Domains 1 and 2).
- The CDC Healthy Housing Reference Manual chapter speaks to conditions inside homes, which links to the built-environment material (Domain 3).
- The Levetin sampling article, the APHL laboratory primer, and the HUD vacuum dust protocol are your investigation toolkit (Domain 4).
- The EPA Exposure Factors Handbook chapter helps you think about exposure assessment when evaluating results (Domain 5).
- Several of the above also inform the guidelines and standards domain, since the federal sources frame what practice looks like.
For a full preparation approach built around these materials, see CEAC Study Guide 2026: How to Pass on Your First Attempt, and for practice with realistic question styles, use the CEAC practice tests.
Eligibility Paths and Application Mechanics
CEAC is an experience-based credential. There is no mandatory training course; what is required is verified experience, a passed examination, and unanimous board approval. ACAC publishes three routes:
| Education Background | Education Credit | Documented Experience |
|---|---|---|
| Qualifying four-year degree | Degree, or stated equivalent of 30 credit hours | Four years of environmental allergen investigation experience |
| Qualifying two-year degree | Degree, or stated equivalent of 15 credit hours | Six years of environmental allergen investigation experience |
| No degree | High-school diploma or GED | Eight years of consulting experience in environmental allergen investigations |
Qualifying education includes microbiology, engineering, science, architecture, industrial hygiene, or related science. Experience must include designing and conducting investigations; being present as a technician while others designed the work is a weaker story. For a fuller discussion, see CEAC Requirements 2026: Eligibility, Prerequisites & How to Qualify.
What You Submit
- The online application
- Four project sheets documenting your investigation work
- Transcripts, when you are claiming education credit
- Required email verifications
Fees, Validity, and Recertification
Fee Mechanics
ACAC's Fees and Payments page lists a USD 100 examination component separate from certification charges, and a USD 100 retake. Its general accredited-certification schedule shows USD 500 initially (USD 400 certification plus USD 100 examination) and USD 400 per two-year renewal.
Read that carefully: these are published category rates, not a separately verified CEAC-specific quotation. The credential-specific application page did not render during review, and accreditation wording conflicts remain. Confirm the applicable total with ACAC rather than assuming your fee category. A fuller breakdown is in CEAC Certification Cost 2026: Complete Pricing Breakdown.
Validity and Renewal
The certification is valid for two years. Current recertification procedures require 40 RCs per term, made up of 10 for continued field activity plus 30 hours of professional development, with evidence retained in case of audit.
Reading the Published Numbers Carefully
ACAC's accredited certification activity summary, as of December 31, 2025, reports for CEAC a 50% examination pass ratio, two applicants in 2025, and 10 current certifications at that date.
Resist the temptation to treat the 50% as a difficulty verdict. With only two applicants in the year, a single result swings the ratio dramatically. Applicant totals can also include licensing-only candidates, so this is not a verified first-attempt pass rate, not a long-run average, and not a forecast for 2026. The small population also tells you something qualitative: this is a niche specialty, which shapes the job market and networking dynamics. For more context, see CEAC Pass Rate 2026: What the Data Shows and How Hard Is the CEAC Exam?.
Key Takeaway
Do not plan around a pass-rate statistic from a tiny sample. Plan around the 75% cut score: be competent in all six domains, and use timed practice to confirm you can hold that standard across 120 questions.
Who Uses This Credential
ACAC does not publish a salary table or employer list for CEAC, so avoid any source claiming precise earnings. Qualitatively, the credential fits professionals who investigate indoor allergen problems: consultants and firms working in indoor environmental quality, industrial hygiene practices, healthy-housing programs, and building-science or remediation-related work. Because it is a niche credential, its value depends on your local market and how clients or employers recognize it. For further analysis, see CEAC Jobs, CEAC Salary Guide 2026, and Is the CEAC Certification Worth It?.
Accreditation: What to Verify
This is the item most worth checking before you make any marketing claim. ACAC's Environmental Allergen Consulting page describes CEAC and CEAI as CESB accreditation applicants, yet the 2025 accredited-activity report includes both. Meanwhile, the public CESB Members list does not show CEAC or CEAI. Absence from a list does not settle status either way.
The practical rule: do not state or imply that the credential is accredited by any third party until you have confirmed it directly with ACAC or CESB. If you are weighing the credential for your career, this is a fair question to put to ACAC before you pay.
Sequencing Your Review by Domain
Since weights are unpublished, spread effort sensibly and weight toward your own gaps. One CEAC-specific ordering logic: learn the problem (people and allergens), then the setting (buildings), then the method (investigation), then the decisions (evaluation and remediation), then the rules.
Domains 1 and 2: People and Allergens
- Read the HHS airborne allergens publication and HUD's asthma brief in full
- Build a one-page map of allergen types, sources, and where each accumulates
Domain 3: The Built Environment
- Work through the CDC Healthy Housing Reference Manual chapter
- Connect ventilation, moisture, and materials to allergen reservoirs
Domain 4: Investigation (give this the most time)
- Study the Levetin sampling article, the APHL laboratory primer, and the HUD vacuum dust protocol
- Practice choosing a method for a described complaint and justifying it
Domains 5 and 6: Decisions and Rules
- Study the EPA Exposure Factors Handbook chapter for exposure reasoning
- Review how guidance documents frame evaluation and remediation
Timed Practice
- Take full-length timed sets at 90 seconds per question using the CEAC Exam Prep practice tests
- Revisit the domain where you miss the most questions
Adjust the schedule to your experience. A practicing allergen investigator may need less time on Domain 4 and more on the regulatory material, while a newcomer from a general science background may need the reverse. Domain 4 is flagged for extra time here because three of the seven assigned publications concern sampling and laboratory practice, which suggests the investigation material is substantial in the reading list even though ACAC publishes no weights.
Frequently Asked Questions
The passing score is 75%, set using the Modified Angoff Method. The exam has 120 closed-book multiple-choice questions and a 3-hour limit, and scores are available immediately with email confirmation.
No. The six domain headings are public, but percentage weights are not published in the reviewed sources. Be skeptical of any resource that quotes exact weights, and prepare across all six domains.
No mandatory training course is required. Eligibility rests on verified experience and education, a passed examination, and unanimous board approval. Any prep course you choose is optional and separate from ACAC's requirements.
It is valid for two years. Current procedures call for 40 RCs per term: 10 for continued field activity plus 30 hours of professional development. ACAC's handbook and program overview use different wording, so confirm the current requirement and keep evidence in case of audit.
Not really. ACAC's activity report lists two applicants in 2025, a very small sample, and applicant totals can include licensing-only candidates. It is not a first-attempt or long-run rate and not a 2026 forecast.
Keep this sheet as a checklist, but verify the flagged conflicts (fees, deadline window, renewal hours, test-day arrival, and accreditation status) directly with ACAC before you commit. Then turn knowledge into exam performance with timed sets from the CEAC Exam Prep practice test site.