CIES Certification

What This Credential Actually Is

Council-certified Indoor Environmental Supervisor, abbreviated CIES, is a professional certification for people who plan, direct and verify the remediation of contaminants inside buildings. It is not an entry-level training certificate and it is not a mold-only credential. The scope covers asbestos, lead, hazardous materials, microbial contaminants and allergens, and chemicals. That breadth is what separates it from narrower mold-remediation certifications.

The acronym is shared by several unrelated credentials in other fields, so be careful when researching. Everything in this article refers only to the Council-certified Indoor Environmental Supervisor credential. If you are still confirming terminology, our explainers on what CIES certification is and what CIES stands for cover the naming in more detail.

Who Issues It and Why Accreditation Matters

The credential is issued by the American Council for Accredited Certification (ACAC) through its CIES Certification Board. The program carries accreditation from the Council for Engineering and Scientific Specialty Boards (CESB), which matters to employers, regulators and clients who want evidence that a certification program meets an independent quality standard rather than simply being a vendor-issued badge.

Exam delivery is handled by Kryterion, Inc., and the examination is a written, computer-delivered test. ACAC does not develop or administer preparation courses, and no mandatory training course or minimum number of training hours is published. In other words, the credential is about demonstrated experience and demonstrated knowledge, not seat time.

Three Eligibility Pathways and the Four Project Sheets

Eligibility is built around a combination of education and documented indoor environmental remediation experience. There are three published pathways:

The experience must cover at least three of these five areas: asbestos, lead, hazardous materials, microbial/allergens, and IH/chemicals/toxicology. Experience must be actual field experience. Classroom exposure and desk-based work will not satisfy the requirement. ACAC's FAQ explains which semester-credit subjects qualify toward the credit-based options.

Writing Project Sheets That Hold Up

Every applicant submits four project sheets, plus educational evidence where applicable and experience verification. Each sheet follows a three-part logic: the problem, your own responsibilities and actions, and the outcome. The emphasis on "your own" is deliberate. Reviewers want to see what you personally decided, supervised or executed, not what the project team accomplished collectively.

• Choose projects that demonstrate supervisory judgment, such as containment design, clearance decisions or worker-protection choices.
• Spread your four sheets across the disciplines in which you claim experience, so the board can see the three-of-five requirement satisfied.
• Describe the outcome in verifiable terms, such as clearance achieved or regulatory compliance maintained.

For a fuller walkthrough of eligibility, see our guide to CIES requirements and how to qualify.

Exam Format and Test-Day Logistics

The examination consists of 120 multiple-choice questions, each with at least four answer options. You have three hours, the test is closed book, and the passing score is 75%, established using the Modified Angoff method. The split between scored and unscored items is not published, so treat every question as if it counts. No separate practical assessment is described.

Delivery Options and Rules

• Testing center or online video proctoring: both are available.
• Fixed question set: the handbook describes a fixed set with randomized item and answer order. Adaptive testing is not described.
• Results: scores are available electronically immediately and confirmed by email.
• Center check-in: two government-issued IDs are required, including one photo ID.
• Online requirements: you supply a computer, an approved webcam and a private location, with at least 2 Mbps upload and download. Phones and tablets are excluded.

With 120 questions in 180 minutes, you have roughly a minute and a half per item. That is generous for recall questions but tight for scenario questions that require you to apply a regulation to a worksite. For perspective on difficulty, read our analysis of how hard the CIES exam is, and for scheduling logistics see the CIES exam dates and scheduling guide.

The Five Competency Areas

The candidate handbook publishes five competency headings. These are unweighted issuer competencies, so there is no official percentage breakdown to optimize around, and the handbook says the board prescribes an exam blueprint without reproducing a public domain chart. Use the five headings as preparation topics, and note that each one addresses engineering controls, cleaning and removal methods, worker safety and applicable regulations. The pattern repeats across all five, so a unified mental framework pays off: for any contaminant, ask what the hazard is, how to control it, how to remove or clean it, how to protect workers, and which regulation governs.

For a deeper treatment of each area, see our complete guide to all five CIES content areas.

The Reference Library You Need to Know

The handbook's bibliography is the closest thing to an official syllabus. Listed preparation references include the ACAC Code of Conduct; 40 CFR 763; 40 CFR 61 Subpart M; 29 CFR 1926.1101; 40 CFR 745; 29 CFR 1926.62; 29 CFR 1910.120; the NYC fungi guidelines (2008); NIOSH Respirator Selection Logic (2004); and the EPA methamphetamine laboratory cleanup guidelines.

A practical approach is to build one study sheet per regulation and record, for each, who it applies to, what it requires, and what triggers it. Our one-page CIES cheat sheet offers a condensed model for that kind of summary.

Fees, Application Timeline and Conflicting Issuer Details

No separate member and non-member fee schedule is published. The full breakdown, with context, is in our CIES certification cost guide.

Application Process and Where Sources Disagree

The current ACAC application page specifies online submission, required email verifications and unanimous board approval. It says the board meets every four to six weeks and refers to a six-month window that includes the examination. The CIES handbook, however, gives 90 days and describes notarized forms and employer affidavits. This conflict between ACAC's own documents is unresolved, so contact ACAC before you start and ask which procedure applies to your application. Build extra time into any plan that depends on a certification date, such as a licensing deadline or a job offer.

Certification vs. State Licensing: The Florida Example

A licensing-only exam result does not confer CIES certification. The reverse is also true: holding the certification does not by itself make you a licensed professional in any state. Florida illustrates the distinction. Indexed content from the Florida Department of Business and Professional Regulation lists this examination among its approved mold-remediation exams, although direct retrieval of that page was blocked during verification, so confirm current status with the regulator.

Even if the exam is approved, the regulator's checklist for the Mold Remediator initial license by examination shows that passing an approved exam is only one component. Separate application, education and experience, fingerprinting and insurance requirements apply. Treat ACAC eligibility and state licensing eligibility as two separate tracks with separate paperwork.

How It Compares With CMRS and CIER

Candidates often weigh this credential against ACAC's Council-certified Microbial Remediation Supervisor (CMRS) and the Council-certified Indoor Environmental Remediator (CIER). The most useful distinction is scope. CMRS centers on mold remediation, per ACAC's Mold Remediation page, while this credential spans five discipline areas and requires experience in at least three of them. If your career is entirely mold work, the broader scope and experience requirement may be more than you need. If you supervise mixed-hazard projects, such as an asbestos and lead abatement that uncovers water damage, the multi-discipline credential matches your actual job.

Check ACAC's current program pages for each credential's exact experience requirements before deciding, since they differ and are updated periodically. Our guide on whether the certification is worth it walks through the decision framework.

Pass Rate, Salary and Return on Investment: What Is Known

Pass-Rate Data Is Thin and Contradictory

No numerical 2025 or 2026 pass rate has been verified. ACAC's accredited certification activity report as of December 31, 2025 shows dashes for applicants and pass ratio, alongside 6 recertifications and 6 current certifications, and this credential is omitted from the 2025 Exam Pass Ratio report. A dash is not a 0% pass rate. For 2024, the sources conflict: the pass ratio report shows 2 exams taken, 2 passed and 100%, while the activity report lists 2 applicants, 0% and 7 current certifications. With candidate counts this small, neither figure is a reliable predictor of your odds, and exam-attempt reports include retakes and licensing-only candidates. See our pass rate analysis for details, and our note on the passing score for what the 75% threshold means in practice.

Salary: No Verified Premium

No reliable salary survey specific to ACAC credential holders has been verified, and no causal earnings premium has been established. The credential's value is more plausibly found in what it unlocks: eligibility for supervisory roles on contracts that specify certified supervision, credibility with clients and regulators, and, in some states, a component of licensing. Pay depends heavily on region, employer type and the disciplines you work in. For a cautious look at the topic, see the salary guide and, for roles, the overview of CIES jobs.

Sequencing Your Preparation by Domain

Because the five areas share a common structure of controls, removal methods, worker safety and regulation, you can sequence study by regulatory density rather than by an arbitrary calendar. The outline below assumes you already work in the field and are filling gaps.

Start with the regulation-heavy areas because they reward precise recall and take longest to absorb. Leave the microbial area for later if you already have field fluency there. For a fuller plan, see the CIES study guide, and consult our overview of CIES training options, noting that ACAC's prep directory did not explicitly list this credential at last check.

Practice with scenario questions, not just flash cards. The competency headings use the phrase "understand and execute," which signals that the exam rewards applied judgment: given a worksite condition, what control, method and protection step comes next? Drill yourself at our practice question bank and explain each answer in terms of the governing regulation.

Staying Certified: Renewal Requirements

Certification is valid for two years. ACAC's current Recertification Procedures specify 40 recertification credits (RCs): 10 for continued field activity and 30 for professional development during the term. You attest to these credits and retain evidence in case of audit, and a current photo is requested. Renewal costs $400.

Other ACAC documents describe the requirement differently: the handbook gives a general 40 RCs, and the program page mentions 20 professional-development hours annually. Follow the current Recertification Procedures page and keep your documentation organized from the first day of your term rather than reconstructing it at the end.

If you are new to the credential, start with our primer on what CIES is, then check the CIES certification overview to confirm you meet the pathway requirements before building a study plan.