- What the CIES Credential Actually Is
- Who Issues It and Why That Matters
- Who Qualifies: Education, Experience and Project Sheets
- The Five Competency Areas
- Exam Format and Test-Day Logistics
- Fees, Application Timeline and Approval
- Certification vs. State Licensing
- How CIES Compares With Mold-Focused Credentials
- Staying Certified: Two-Year Renewal
- Who Uses the Credential and What It Might Be Worth
- A CIES-Specific Preparation Roadmap
- Frequently Asked Questions
- CIES means Council-certified Indoor Environmental Supervisor, issued by ACAC's CIES Certification Board, not any other credential sharing the acronym.
- The exam is 120 multiple-choice questions in three hours, closed book, with a 75% passing score.
- Initial cost is $500 for a two-year term: $100 exam plus $400 certification, including a $100 nonrefundable processing fee.
- Applicants must document experience in at least three of five areas and submit four project sheets.
What the CIES Credential Actually Is
CIES stands for Council-certified Indoor Environmental Supervisor. It is a professional certification for people who plan, supervise and carry out remediation work in indoor environments. The scope is deliberately broad: it spans asbestos, lead, hazardous materials, microbial contaminants and allergens, and chemicals. A candidate is expected to understand engineering controls, cleaning and removal methods, worker safety and the regulations that apply in each area.
That breadth is what separates CIES from narrower credentials. A mold-only certification asks you to prove you can handle one contaminant family. CIES asks whether you can supervise remediation across several, which is why the application demands documented field experience rather than just coursework. If you have seen the acronym used elsewhere, set those meanings aside. On this site, and throughout this article, CIES refers only to the ACAC credential described here. For quick definitions of the term itself, see What Does CIES Stand For?
Who Issues It and Why That Matters
The certification is issued by the American Council for Accredited Certification (ACAC) through its CIES Certification Board. The program is accredited by the Council for Engineering and Scientific Specialty Boards (CESB). Accreditation by a specialty-board council matters to employers and regulators because it signals that the certification process, including exam development, has been reviewed against recognized standards.
The examination itself is delivered through Kryterion, Inc. The passing score of 75% was set using a Modified Angoff method, a standard-setting approach in which subject-matter experts judge how a minimally competent candidate would perform on each item. This is worth knowing because it means the cut score reflects a judgment about competence, not a curve against other test-takers. For more on how scoring works, read CIES Passing Score 2026: Exactly What You Need to Pass.
Who Qualifies: Education, Experience and Project Sheets
CIES is not an entry-level credential. Eligibility rests on a combination of education and documented indoor environmental remediation experience, and there are three published pathways:
| Education Background | Documented Remediation Experience |
|---|---|
| Related four-year postsecondary degree, or 30 qualifying college credits | Four years |
| Related two-year degree, or 15 qualifying credits | Six years |
| High school diploma or GED | Eight years |
Experience must cover at least three of these five areas: asbestos, lead, hazardous materials, microbial/allergens, and industrial hygiene/chemicals/toxicology. ACAC requires actual field experience, and its FAQ explains which semester-credit subjects qualify toward the education component.
The Four Project Sheets
Beyond years on the job, you must submit four project sheets, along with educational evidence where applicable and experience verification. ACAC describes each sheet as a three-part narrative: the problem, your own responsibilities and actions, and the outcome. The emphasis on your own role is important. A sheet describing what a crew or company did will not demonstrate your supervisory competence; one describing the decisions you personally made will.
For the full eligibility walkthrough, including how to qualify, see CIES Requirements 2026: Eligibility, Prerequisites & How to Qualify.
The Five Competency Areas
ACAC's candidate handbook publishes five competency headings. These are issuer-stated preparation topics. No public formal exam-domain chart or percentage weighting has been verified, so no area should be treated as the "heaviest" without evidence. Each competency addresses engineering controls, cleaning and removal methods, worker safety and applicable regulations.
Domain 1: Understand and execute successful remediation of asbestos in the indoor environment
Expect questions rooted in federal asbestos rules and work-practice controls.
- Regulatory references listed by ACAC include 40 CFR 763, 40 CFR 61 Subpart M and 29 CFR 1926.1101
- Containment, negative-pressure engineering controls and removal methods
- Worker protection, respirator selection and waste handling
Domain 2: Understand and execute successful remediation of lead in the indoor environment
Lead work spans both occupied-space hazards and worker exposure.
- 40 CFR 745 and 29 CFR 1926.62 are named in the preparation references
- Dust control, cleaning verification and safe removal or stabilization methods
- Worker exposure protections and medical-surveillance concepts
Domain 3: Understand and execute successful remediation of hazardous materials in the indoor environment
This is the broadest and most varied area, covering emergency-response-style and site-cleanup thinking.
- 29 CFR 1910.120 (hazardous waste operations and emergency response) appears in the reference list
- EPA Voluntary Guidelines for Methamphetamine Laboratory Cleanup is a listed reference
- Mercury is addressed, but the handbook's body-of-knowledge and study-guide descriptions differ: one names EPA Region 5, section 5, the other the National Elemental Mercury Response Guidebook, section 9.4. Study both
Domain 4: Understand and execute successful remediation of microbial contaminants and allergens in the indoor environment
This is the area most mold-trained professionals already know, but CIES expects it as one competency among five.
- The New York City Department of Health and Mental Hygiene Guidelines on Assessment and Remediation of Fungi in Indoor Environments (2008) is a listed reference
- Source control, containment, cleaning methods and clearance concepts
- Respiratory protection logic, including the NIOSH Respirator Selection Logic (2004)
Domain 5: Understand and execute successful remediation of chemicals in the indoor environment
Chemical remediation draws on industrial hygiene and toxicology principles.
- Chemical hazard evaluation, exposure pathways and controls
- Appropriate PPE and respirator selection based on contaminant and concentration
- Safe cleaning and removal methods and regulatory duties
The handbook also lists the ACAC Code of Conduct among preparation references, so ethics expectations are part of what you should know. A caution from the public study guide itself: its selected pages are examples, not exhaustive coverage, and it advises comprehensive study of the references. For a deeper per-area breakdown, see CIES Exam Domains 2026: Complete Guide to All 5 Content Areas.
Exam Format and Test-Day Logistics
The CIES exam is a computer-delivered written examination of 120 multiple-choice questions, each with at least four answer options. You have three hours, and the exam is closed book. The scored/unscored split of questions is not published. There is no separate practical assessment. The handbook describes a fixed question set with randomized item and answer order, and adaptive testing is not described. Whether a calculator is permitted is unverified, so confirm that with ACAC before test day.
Testing Center or Online
Both proctored testing-center delivery and online video-proctored delivery are available. Scores are available electronically immediately and confirmed by email.
- Testing center: Bring two government-issued IDs, including one photo ID. The current Examinations page asks for arrival 15 minutes early, while the handbook says 30 minutes. Plan for the longer window.
- Online: You supply a computer, an approved webcam and a private location. ACAC specifies at least 2 Mbps upload and download speeds and excludes phones and tablets.
For how demanding the format is in practice, see How Hard Is the CIES Exam? Complete Difficulty Guide 2026.
Fees, Application Timeline and Approval
ACAC publishes a single fee schedule with no separate member and non-member pricing:
| Item | Fee (USD) |
|---|---|
| Examination | $100 |
| Certification (includes a $100 nonrefundable processing fee) | $400 |
| Initial total, two-year term | $500 |
| Retake | $100 |
| Renewal | $400 |
The fee page is the source of record; see CIES Certification Cost 2026: Complete Pricing Breakdown for the full picture.
An Issuer Conflict You Should Know About
ACAC's current application page specifies online submission with required email verifications, a six-month window that includes the examination, and unanimous board approval, with the board meeting every four to six weeks. The CIES handbook, by contrast, gives a 90-day window and describes notarized forms and employer affidavits. This conflict is unresolved in the public materials. Before you invest in notarizations, contact ACAC and ask which process currently applies. Either way, build slack into your schedule, since board approval depends on meeting cycles. Scheduling details are covered in CIES Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Certification vs. State Licensing
This is the most commonly misunderstood point. A licensing-only exam result does not itself confer CIES certification. Some state regulators accept the CIES exam as one route to a license, and Florida is the frequently cited example: the Florida Department of Business and Professional Regulation's mold-related services examination listing has been reported to include CIES among accepted examinations. We could not fully verify that page directly because a fresh retrieval returned an access error, so treat it as something to confirm with the regulator rather than a settled fact.
Key Takeaway
Passing an approved exam is only one piece of a state license. The regulator's checklist for Florida's Mold Remediator initial license also involves separate application, education and experience, fingerprinting and insurance requirements. ACAC certification eligibility and state licensing eligibility are two different tracks, so verify both before you spend money on either.
How CIES Compares With Mold-Focused Credentials
Searchers often ask how CIES stacks up against ACAC's mold credentials, such as CMRS, or against CIER. The honest answer is that scope is the main difference. CIES spans five remediation disciplines and requires experience in at least three. Mold-focused credentials concentrate on microbial work, which maps to only one of CIES's five competencies. Check ACAC's mold remediation page and its published requirements for each credential, since the experience thresholds differ.
| Factor | CIES | Mold-focused credentials |
|---|---|---|
| Scope | Asbestos, lead, hazmat, microbial, chemicals | Primarily microbial contaminants |
| Experience breadth | At least three of five areas | Check ACAC's current requirements per credential |
| Study load | Federal regulations across several contaminant families | Narrower, mold-centered |
Candidates with strong mold backgrounds frequently underestimate how much asbestos, lead and chemical regulation they must learn. If that describes you, budget extra time for Domains 1, 2, 3 and 5.
Staying Certified: Two-Year Renewal
CIES is valid for two years. ACAC's current recertification procedures specify 40 recertification credits (RCs) per term: 10 for continued field activity and 30 for professional development. You attest to the credits and retain evidence in case of audit, and a current photo is requested. Renewal costs $400.
Be aware that the public materials are not perfectly consistent. The handbook gives a general 40-RC figure, and the program page mentions 20 professional-development hours annually. Follow the current Recertification Procedures page and confirm with ACAC. Start logging credits in your first year rather than scrambling in the final months.
Who Uses the Credential and What It Might Be Worth
The natural audience is remediation supervisors and project managers, industrial hygiene and environmental consulting staff, abatement and restoration contractors, and facilities or environmental health and safety professionals who oversee contaminated-building work. Employers value the credential as evidence that a supervisor can manage multi-hazard projects, and some state licensing paths recognize the exam.
On earnings, we will not pretend to precision we do not have. No reliable salary survey specific to ACAC CIES holders has been verified, and there is no established causal pay premium. Pay depends heavily on region, employer type, hazard specialty and seniority. The better question is whether the credential opens doors that your experience alone does not. Explore that thinking in Is the CIES Certification Worth It? Complete ROI Analysis 2026 and CIES Salary Guide 2026: Complete Earnings Analysis.
What About the Pass Rate?
No numerical 2025 or 2026 CIES pass rate has been verified. ACAC's 2025 activity report shows dashes for CIES applicants and pass ratio, with 6 recertifications and 6 current certifications, and CIES is omitted from the 2025 exam pass ratio report. A dash is not a 0% pass rate. Historical 2024 figures conflict between ACAC reports and involve only two candidates, so they should not be treated as meaningful. Population this small makes any percentage unreliable. See CIES Pass Rate 2026: What the Data Shows.
A CIES-Specific Preparation Roadmap
No mandatory preparation course or minimum training-hour requirement is published, and ACAC does not develop or administer prep courses. Its prep directory did not explicitly list CIES. That leaves self-directed study against the handbook's reference list. Sequence your weeks by regulatory density, not by what feels comfortable:
Asbestos (Domain 1)
- Read 40 CFR 763, 40 CFR 61 Subpart M and 29 CFR 1926.1101
- Map containment and engineering controls to each regulation
Lead (Domain 2)
- Work through 40 CFR 745 and 29 CFR 1926.62
- Contrast work-practice rules with worker-exposure rules
Hazardous Materials (Domain 3)
- Study 29 CFR 1910.120 and the methamphetamine cleanup guidelines
- Read both mercury references and note where they differ
Microbial and Chemicals (Domains 4 and 5)
- Review the NYC fungi guidelines and NIOSH Respirator Selection Logic
- Practice matching contaminant, exposure and PPE decisions
Spend the final stretch on mixed-topic questions under timed conditions, since the real exam interleaves all five areas across 120 items in three hours. Use the CIES Study Guide 2026: How to Pass on Your First Attempt for resource lists and the CIES Cheat Sheet 2026: One-Page Review of Must-Know Facts for a last-day refresher. When you want realistic question practice, try the CIES practice tests and review explanations back to the underlying regulation.
Be cautious with public question dumps and shared "exam review" documents. Their completeness, accuracy and alignment to the reference list are unverified, and a memorized wrong answer is worse than none. Questions that explain the regulation behind the answer are the safer investment. You can also start with a CIES practice test to find which of the five competencies needs the most work.
Frequently Asked Questions
It stands for Council-certified Indoor Environmental Supervisor, a certification issued by ACAC's CIES Certification Board. Other credentials share the acronym, but this article and this site cover only the ACAC credential.
The exam has 120 multiple-choice questions, each with at least four options, delivered in three hours as a closed-book test. The passing score is 75%, set using a Modified Angoff method.
The initial total is $500 for a two-year term: a $100 examination fee plus a $400 certification fee that includes a $100 nonrefundable processing fee. A retake is $100 and renewal is $400.
Yes, through the pathway requiring a high school diploma or GED plus eight years of documented indoor environmental remediation experience. That experience must cover at least three of the five areas, and you must also submit four project sheets and experience verification.
No. A licensing-only exam result does not confer CIES certification, and state licenses typically require additional steps such as application, education or experience, fingerprinting and insurance. Confirm the current rules with your state regulator.