What Is CD Certification?

What the CD Credential Actually Is

Course Director certification is issued by the Council for Accreditation in Occupational Hearing Conservation (CAOHC). The official program name is Course Director (CD), and CAOHC describes holders as CAOHC-approved Course Directors. If you have come across other credentials that abbreviate to "CD," set them aside: this article covers only the CAOHC instructor qualification.

A Course Director is not simply a hearing conservationist who has passed a test. The credential authorizes you to direct CAOHC-approved occupational hearing conservation courses, the training that produces certified hearing conservationists who run industrial and workplace hearing conservation programs. In practical terms, the CD is the person accountable for the curriculum, the instruction and the paperwork around a course.

If you are still sorting out terminology, our short explainers on what CD is and what CD stands for cover the naming question, while this article focuses on the certification itself.

Who Needs a Course Director Credential

The credential is aimed at experienced professionals who want to lead OHC training rather than only practice hearing conservation. Typical candidates already hold a qualifying professional license or certification and have spent substantial time in the field: running hearing conservation programs, conducting audiometric testing, supervising program elements or teaching related material.

Because eligibility is documentation-heavy, the CD is not an entry-level credential. You build toward it through years of relevant work and a supervised teaching experience. Candidates commonly include occupational health professionals, audiologists and other licensed clinicians who are comfortable in a classroom or training setting. Note that CAOHC's current web eligibility language includes physician assistants, while the November 2025 policy manual lists qualifying professions differently, so confirm your own profession's status with CAOHC before investing in the application.

Eligibility: What CAOHC Wants Documented

Eligibility is where most of the real work happens. CAOHC does not open ordinary registration until your documentation is approved. The full breakdown lives in our CD requirements guide; here is the structure at a glance.

The 1,000-hour rule in practice

The hours must be relevant and recent (within five years), and they cannot all come from a single kind of work. You need to show activity across at least three of the specified categories. Candidates who have only ever done one thing, such as audiometric testing, may need to broaden their documented experience before applying.

The supervised course requirement

You must complete an entire supervised OHC course in an in-person or hybrid format, serving as adjunct faculty or a practicum assistant. This is where a current Course Director verifies your performance, so build that relationship early. A verification letter from someone who watched you teach carries more weight than a generic reference.

How the Online Open-Book Exam Works

The Course Director exam is delivered online through the CAOHC Learning Center. It is open-book, and your progress is saved, so you can step away and return. You have a ten-day window to complete it. It is not a single long sitting, and it is not a multi-hour proctored marathon.

• Passing score: 80%. See our CD passing score breakdown for what that means for your preparation.
• Attempts: Two attempts within the completion window.
• If both attempts fail: You must repeat the workshop and the exam.
• Not published: The number of questions, the split between scored and unscored items, the exact item types and the pass rate. We do not guess at these, and you should be wary of any source that quotes them confidently. Our CD pass rate article explains what is and is not known.

The open-book design changes how you should prepare. You will not be rewarded for memorizing trivia, but you also cannot lean on the book to rescue you from not understanding the material. Questions reward candidates who know where the answers live in CAOHC's materials and can apply them to course-direction scenarios quickly. For a candid look at the challenge, read how hard the CD exam really is.

Fees and Registration Mechanics

CAOHC prices the credential in pieces. The exam and the workshop are separate line items, and the member versus non-member distinction is not published.

The totals above are our arithmetic from the published line items, not a single advertised package price. For a fuller treatment, including what you may spend on materials and your supervised-course logistics, see the CD certification cost breakdown. Scheduling details are covered in CD exam dates and deadlines.

The workshop is training, not testing

The CD workshop runs eight hours, and that is training time. It is not the exam, and it is not a continuous eight-hour test. Candidates sometimes conflate the two, which leads to wrong expectations about how long the evaluation takes. The exam itself is the open-book, ten-day-window assessment described above.

The Five Content Areas You Prepare For

CAOHC publishes five curriculum areas for the Course Director workshop. These are the topics the issuer teaches, and we use them as our study framework. They are unweighted: CAOHC has not published a weighted exam blueprint, so no area should be assumed to carry more points than another. Any practice-question allocations on this site are editorial choices, not official weights. Our complete guide to the five CD content areas goes deeper on each.

Scheduling the Five Areas Across Your Prep

Because the exam is open-book with a ten-day window, your preparation should emphasize navigation and application over rote recall. A sensible sequence puts the administrative, rule-bound material first, since that is where precise answers matter most. If you want a full plan, our CD study guide expands on this outline, and the CD cheat sheet works well as a final-week review.

Five-Year Validity and Renewal Paths

The credential is valid for five years. To renew, you have two routes: complete the workshop plus the renewal exam, or take the eligible exam-only route. The exam-only route requires that you meet at least two of the following:

1. Directed ten qualifying OHC courses
2. Served two years on a CAOHC committee or task force
3. Earned ten relevant continuing-education contact hours
4. Taught one approved CD workshop

Ten CE hours is one option among these, not a universal standalone renewal quota. Hours alone do not renew a Course Director credential.

Extensions and related credentials

CAOHC may grant extensions of up to six months at its discretion. Submit your request at least 30 days before expiration. A failed exam does not qualify you for an extension. Also remember that renewing a separate certified hearing conservationist credential (COHC) is its own process and does not renew your Course Director status.

Who Hires and Where the Credential Fits

Demand for Course Directors comes from organizations that deliver or sponsor CAOHC-approved training: occupational health service providers, industrial and manufacturing employers with in-house training functions, safety consultancies, universities and professional training organizations. The credential positions you to lead courses and, in many settings, to take on training or program-management responsibility.

We deliberately avoid quoting salary numbers here, because no reliable, CD-specific figure is published. For a qualitative discussion of earnings, see the CD salary guide, and to weigh the investment, read whether the certification is worth it. If you are exploring openings, our overview of CD jobs and CD training pages are good next stops. For a broader summary, the main CD certification page collects the essentials.

Ready to test yourself against CD-style scenarios? Our CD practice test hub offers practice built around the five Course Director content areas.

Frequently Asked Questions