What Is A COHN?

The Short Answer: What a COHN Actually Is

A COHN is a Certified Occupational Health Nurse: a registered nurse who has demonstrated specialty knowledge in protecting and promoting the health of working populations. The letters are earned by passing a standardized certification examination administered under the American Board for Occupational Health Nurses, Inc. (ABOHN). They are not a license. They sit alongside your RN license as proof that you practice, and have been tested, in the occupational health setting.

If you have seen the same four letters attached to other credentials elsewhere, set those aside. On this site, and throughout this article, COHN refers only to the occupational health nursing certification. If you want a quick orientation to the terminology itself, our short explainers on what COHN stands for and the meaning of COHN cover the naming question, while this article goes deeper into what the credential involves in practice.

Who Awards the Credential

ABOHN is the certifying body. It sets the eligibility rules, publishes the candidate handbook, defines the content outline, and governs recertification. The examination itself is delivered through Assessment Systems Corporation (ASC), which offers testing at a physical test center or through live remote proctoring via MonitorEDU. That means you can sit for the exam either in person or from a qualifying space at home or work, depending on which delivery option you choose when scheduling.

The governing document for candidates is the ABOHN handbook (the current edition is dated March 2026). Treat it as the source of truth. Eligibility details, fee schedules, and policies can change between handbook editions, so confirm anything time-sensitive against the ABOHN site before you apply. For a deeper walkthrough of how the credential is structured as a whole, see our overview of what COHN certification is.

What a COHN Does in a Workplace

Occupational health nursing is a distinct specialty because the patient is both an individual and a workforce. A COHN's responsibilities typically span four overlapping areas:

• Clinical care of workers. Assessing and treating work-related injuries and illnesses, triaging acute complaints, and coordinating referrals when care exceeds the on-site scope.
• Case management. Guiding an injured or ill employee from first report through treatment, work restrictions, modified duty, and return to work, while communicating with supervisors, providers, and payers.
• Risk and compliance. Recognizing workplace hazards, supporting surveillance and monitoring programs, and helping the organization meet regulatory obligations and recordkeeping expectations.
• Program leadership. Designing, running, and evaluating health and safety programs, using data to show what is working and where improvement is needed.

Notice how much of this is population-level and system-level thinking. A floor nurse asks, "What does this patient need?" A COHN asks that and also, "Why did three people from the same line report the same complaint this month, and what does that mean for the program?" That second question is the heart of the specialty and a recurring theme on the exam.

Where COHNs Are Hired

Because workers exist in every industry, so do occupational health nurses. Common employers and settings include:

• Manufacturing and heavy industry, where injury prevention, hearing conservation, and respiratory protection programs are central.
• Healthcare systems, where employee health services manage immunizations, exposure follow-up, and injury care for staff.
• Corporate and office environments, where wellness, ergonomics, and case management take priority.
• Occupational medicine clinics that serve many employers through pre-placement exams, injury treatment, and fitness-for-duty evaluations.
• Utilities, logistics, construction, and government agencies, where safety-sensitive work raises the importance of surveillance and compliance.
• Insurers, third-party administrators, and consulting firms, where nurses apply case management and program expertise at scale.

Roles range from a sole on-site nurse running an entire health program to a corporate or regional manager overseeing multiple sites. If you are exploring what's out there, our page on COHN jobs goes into role types, and our COHN salary guide addresses compensation considerations.

The Three Exam Domains

The exam content is organized into three domains. ABOHN's official allocation of scored items is 72 / 40 / 23 across them, expressed as item counts rather than percentage labels. Clinical Practice and Case Management is the largest domain by a wide margin, which should shape where you spend your hours. For the full breakdown, read our complete guide to the COHN exam domains.

How the Exam Works

Format at a glance

What the 25 pretest items mean for you

Of the 160 questions, 25 are pretest items that do not count toward your score. They are being evaluated for future exams, and you will not know which ones they are. The practical consequence is simple: treat every question as if it counts, and do not let a strange or unfamiliar item rattle you. Some of those puzzling questions are likely the unscored ones.

What the question style tends to reward

Occupational health items are usually scenario-driven. You are presented with a worker, a workplace situation, or a program problem and asked for the best next action, the most appropriate interpretation, or the priority step. Several options may look plausible, so the skill being tested is judgment: identifying the answer that best fits nursing scope, confidentiality rules, regulatory expectations, and the employer-employee dynamic all at once. Because the exam is closed-book, you cannot look up a standard mid-question. You need working fluency with the core concepts, not just the ability to find them.

Eligibility: Hours, Licensure, and Education

To sit for the COHN exam, you need to be a registered nurse (or hold an international equivalent) and have accumulated 3000 hours of occupational health practice within the previous five years. The five-year lookback matters: it is meant to confirm that your experience is current, not just historical. ABOHN also specifies certain education alternatives for candidates who do not meet the standard path, and those alternatives require approval from the board, so do not assume an alternate pathway applies to you until you have confirmed it in writing.

Fees and Registration

The cost structure is straightforward. There are two fees:

• Application fee: $150
• Examination fee: $400
• Total: $550

Registration runs through ABOHN, with testing delivered through ASC. After your application is approved, you schedule your sitting and choose either a test center or live remote delivery. For a broader view of what you may also spend on preparation and later maintenance, see our COHN certification cost breakdown, and for timing questions, our page on COHN exam dates and scheduling.

The Passing Standard and the Published Pass Rate

ABOHN uses an Angoff-based passing standard. In plain terms, subject-matter experts judge how a minimally competent candidate would perform on each item, and the cut score is derived from those judgments. This means the passing line is tied to a competence standard rather than to a fixed curve against other test-takers.

On the published statistics, be careful. ABOHN reports a pass rate of 65% for 2025, but its statistics page also lists 57 and 85 figures, and that discrepancy is unresolved. Until ABOHN clarifies, the responsible reading is that the exact pass rate is uncertain. We recommend planning to be well prepared rather than anchoring on any single number. Our COHN pass rate analysis and COHN passing score guide discuss how to interpret this, and how hard the COHN exam is covers the difficulty question more broadly.

Keeping the Credential: Recertification

The COHN credential runs on a five-year cycle. To recertify, you must maintain:

• Active RN status
• 3000 hours of practice
• 50 related continuing nursing education (CNE) hours

There is also an annual maintenance/recertification fee of $150. The key planning lesson is to log your practice hours and keep CNE certificates organized as you go, rather than reconstructing them at the end of the cycle. Choose CNE that actually relates to occupational health so it counts and so it strengthens your day-to-day practice.

Sequencing Your Preparation

This is the one place we will talk about study scheduling, and we will tie it directly to the exam's structure. Because the domains are weighted so unevenly, your calendar should be too. A sensible eight-week arc looks like this:

For a fuller plan and resources, see our COHN study guide, and for a quick final review, the COHN cheat sheet. If you want structured preparation, the COHN practice test platform lets you drill by domain and simulate the timed format. Our COHN training overview also covers learning options.

Is It Worth Pursuing?

That depends on your goals. The certification signals specialty expertise to employers, which can matter when applying for occupational health roles, moving into program or management positions, or distinguishing yourself in a competitive market. The costs are modest relative to many professional credentials: $550 to sit, plus ongoing maintenance. The larger investment is the preparation time and the practice hours you need to qualify. For a structured look at the tradeoffs, read whether the COHN certification is worth it. If you are ready to begin testing yourself against realistic questions, you can start with a COHN practice exam here.

Frequently Asked Questions