OHC Requirements 2026: Eligibility, Prerequisites & How to Qualify

What "Requirements" Actually Means for the Occupational Hearing Conservationist

When people search for the requirements to become an Occupational Hearing Conservationist, they usually expect a list of degrees, licenses, or years of experience. The credential, issued by the Council for Accreditation in Occupational Hearing Conservation (CAOHC), works differently. It is a training-and-performance certification: what qualifies you is not your background but what you complete, demonstrate, and pass. Successful candidates earn the COHC designation.

This article covers the initial certification path only. It does not cover the separate Course Director or Professional Supervisor/Audiologist (CPS/A) certifications, which carry their own criteria. If you are still orienting yourself to the credential itself, start with What Is OHC Certification? and then return here to map out the practical steps.

The official scope for this guide is drawn from CAOHC's OHC Handbook and Instructions (revised February 2023) and the Course Director Policies and Procedures Manual (revised November 2025). Where CAOHC's own materials disagree with each other, this article says so rather than papering over it.

No Enrollment Prerequisites: What That Does and Doesn't Mean

CAOHC lists no course-enrollment prerequisites for the Occupational Hearing Conservationist course. You do not need a particular degree, a clinical license, or a prior hearing-health job title to sign up. That is why the credential draws such a varied crowd: safety coordinators, occupational health nurses, industrial hygienists, plant technicians, military hearing-program staff, and consultants who run testing on-site for employers.

The Three Things You Must Complete

Every candidate for initial certification must satisfy all three of the following. Missing any one means you are not certified, regardless of how well you did on the others.

Notice that the 75-minute exam timer and the 20-hour course minimum measure entirely different things. The 20 hours is instructional time in the approved course; the 75 minutes is the clock on your initial written exam. Candidates sometimes conflate the two when planning their schedules.

The Approved Course: Hours, Content, and How You Register

Minimum hours

The approved course must run at least 20 hours. Individual Course Directors design the schedule: some deliver it as consecutive full days, others spread it across multiple sessions. The format is the Course Director's decision, so ask about structure before you commit.

How registration and tuition work

Registration is not handled through a central CAOHC enrollment page. Tuition and course registration are managed by the Course Director who is running your course. Exam administration runs through the CAOHC Learning Center, with the Course Director or an approved proctor overseeing it. In practical terms, your first step is finding an approved course offering and contacting that Course Director directly about dates, location or format, and cost.

Because pricing is set at the course level rather than by a single fixed schedule, comparing offerings matters. Our breakdown in OHC Certification Cost 2026 walks through the categories of expense to ask about, including possible proctoring fees on retakes.

What the course teaches

The course is built around the same eleven-heading blueprint the exam draws from. Expect classroom instruction on the physics of sound and ear anatomy, regulatory frameworks, noise measurement, and counseling, paired with supervised skills practice. For a closer look at what each area covers, the OHC training overview and the complete domains guide are good companions.

The Two Practicums: Audiometry and HPD Fitting

The practicums are what separate this credential from a purely knowledge-based test. You must demonstrate satisfactory performance in both:

Because both practicums are pass/fail on competence rather than scored on a curve, they reward hands-on repetition. Candidates who treat them as an afterthought to the written exam are the ones who tend to be surprised.

The Written Exam: Format, Timer, and Passing Mark

The written exam follows a consistent format:

• Question style: four-option, single-best-answer multiple choice
• Minimum to pass: 70%
• Languages: English or Spanish
• Initial exam timer: 75 minutes
• Timer behavior: it cannot be paused, but you can flag questions and revisit them

Candidates read the exam instructions in advance; CAOHC publishes them as a standalone document. Practicing with the flag-and-return workflow matters, since an unpausable timer punishes anyone who stalls on a single hard item. You can pressure-test that skill on the OHC practice test.

Attempts and Retakes

You are allowed a maximum of three attempts at the written exam. Retakes are arranged through your Course Director, and they must happen within 30 days of the preceding attempt. Be aware that retakes may involve proctoring fees, again set at the course level.

Two practical implications follow. First, the 30-day window means you should begin reviewing your weak domains immediately after an unsuccessful attempt rather than waiting. Second, because the attempt cap is firm, your first sitting deserves real preparation. Data on how candidates fare is limited, and we do not invent figures; our pass rate discussion explains what can and cannot be said responsibly.

The Eleven Blueprint Domains You Will Be Tested On

The OHC Handbook's page 6-8 headings are explicitly framed as an exam blueprint. CAOHC does not publish percentage weights for them, so there is no supported "highest-weight" domain. Do not trust any source that claims one area counts for a specific share of the exam. Plan to be competent across all eleven:

1. Hearing Conservation (Overall) - the framework and purpose of a hearing conservation program
2. Anatomy, Physiology and Diseases of the Ear - outer, middle, and inner ear structure and function, plus conditions that affect hearing
3. Hearing and the Physics of Sound and Performing and Explaining a Hearing Test - frequency, intensity, decibels, and how to explain results to a worker
4. Federal and State Regulations Related to Occupational Noise-Induced Hearing Loss - the regulatory requirements that drive program obligations
5. Audiometer and Testing Environment - equipment requirements and booth or room conditions
6. Audiometric Techniques and Testing - conducting valid threshold tests
7. Audiometric Review and Evaluation - baselines, comparisons, and recognizing shifts
8. Noise Measurement and Control - sound measurement concepts and control strategies
9. Hearing Protection Device (HPD) Fitting - selection, fitting, and effective use
10. Counseling and Training - communicating with and motivating workers
11. Recordkeeping and the Hearing Conservation Team - documentation duties and who does what

Several of these directly mirror the practicums, which is intentional: what you do with your hands in the course reappears as written questions. Domains 5, 6, and 9 in particular reward candidates who have actually handled the equipment. The full explanation of each area lives in the OHC exam domains guide.

Sequencing Your Preparation Around the Blueprint

You do not need a generic study system here; you need an order that respects how the domains build on each other. Concepts in the physics and anatomy domains underpin the audiometry domains, which in turn underpin review and evaluation. Here is a sequence that follows that dependency chain:

For a broader, step-by-step approach, the OHC study guide expands on materials and pacing, and the cheat sheet is useful for last-day review of must-know facts.

Keeping the COHC Designation Current

Meeting the initial requirements is not a permanent solution. Certification is valid for five years from course completion. To renew, you must complete:

• A minimum 8-hour refresher course
• Both practicums again (audiometric and HPD fitting)
• The separate recertification exam: 30 questions in 45 minutes

If you cannot meet the deadline, you may request an extension, but the request must be made at least 30 days before your certification expires. Missing that window removes the option. Calendar your expiry date early, and revisit the details in CAOHC's recertification page and FAQ.

When you are ready to test your recall against realistic four-option questions, the OHC Exam Prep practice test lets you drill by domain and build the timing discipline the unpausable clock demands.

Frequently Asked Questions