- The Core Requirements at a Glance
- The RN License Requirement
- The 3,000 Practice Hours Requirement
- Education Alternatives and Approval
- Application and Fee Mechanics
- What You Qualify to Sit For
- Matching Your Experience to the Exam Domains
- A Qualification Timeline for Your Application
- Requirements After You Pass
- Common Eligibility Pitfalls
- Frequently Asked Questions
- You need an RN license (or international equivalent) plus 3,000 occupational-health practice hours within the previous five years.
- Total cost is $550: a $150 application fee plus a $400 examination fee.
- The exam has 160 multiple-choice questions (135 scored, 25 pretest) delivered over 3 hours, closed-book.
- Education alternatives to the standard pathway exist, but they require approval from ABOHN before you apply.
The Core Requirements at a Glance
The Certified Occupational Health Nurse (COHN) credential is awarded by the American Board for Occupational Health Nurses, Inc. (ABOHN). Unlike entry-level nursing credentials, it is designed for nurses who have already spent meaningful time working in occupational and environmental health settings. Eligibility is therefore built around two pillars: a current nursing license and documented, recent, specialty-specific practice.
| Requirement | What ABOHN Expects |
|---|---|
| Nursing licensure | Registered nurse (RN) license or international equivalent |
| Practice experience | 3,000 hours of occupational-health practice |
| Recency window | Hours must fall within the previous five years |
| Education alternatives | Specified options available, subject to approval |
| Application fee | $150 |
| Examination fee | $400 (total $550) |
| Test delivery | Assessment Systems Corporation (ASC), test center or MonitorEDU live remote |
Think of these as a gate you must pass before you ever open a study guide. Candidates who treat eligibility as an afterthought often discover documentation gaps weeks into their preparation. If you are still deciding whether the credential suits your career, our overview of COHN certification explains what the credential represents and who it is built for.
The RN License Requirement
The foundation of COHN eligibility is nursing licensure. ABOHN requires a registered nurse license or an international equivalent. This is not a credential you can pursue as a non-nurse safety professional; it is explicitly a nursing certification, which is why the exam leans so heavily on clinical judgment, case management, and nursing-scope decision-making.
Practical points about licensure
- Keep the license active. An unencumbered, current license is the baseline expectation, and active RN status also remains a condition of recertification later.
- International nurses. The handbook recognizes an international equivalent to the RN license. If your license was issued outside the United States, review the handbook language and contact ABOHN early about what documentation they will accept.
- Name consistency. The name on your license, application, and government-issued ID should match. Mismatches create avoidable delays at registration and again at the testing check-in.
If you are weighing the career impact before committing, see Is the COHN Certification Worth It? for a fuller look at how the credential fits into an occupational health nursing career.
The 3,000 Practice Hours Requirement
The practice-hours rule is where most of the real qualification work happens. You need 3,000 hours of occupational-health practice, and those hours must fall within the previous five years. The five-year lookback matters: ABOHN is certifying current competence, not historical experience. A nurse who worked in an occupational clinic fifteen years ago and has since moved to a different specialty will generally not qualify on that older experience alone.
What qualifying occupational health work looks like
Occupational health nursing spans a wide range of settings and responsibilities. The exam itself is organized around the work you are expected to have done, so a useful self-check is to map your daily duties to the three exam domains:
- Clinical Practice and Case Management: injury and illness assessment, treatment and triage, workers' compensation case management, return-to-work and modified-duty coordination, fitness-for-duty and surveillance examinations.
- Risk and Compliance: hazard recognition, exposure assessment, regulatory requirements, recordkeeping, medical surveillance programs, and workplace safety compliance.
- Program Management and Quality Assurance: designing and evaluating health and wellness programs, managing budgets and resources, measuring outcomes, and improving quality.
If your hours come primarily from one area, such as pure clinic-based treatment, you may find the program-management and compliance content less familiar. That does not affect eligibility, but it should shape your preparation. Our COHN exam domains guide breaks down all three content areas in detail.
Documenting your hours
Keep records as you go. Supervisor letters, job descriptions, employment verification, and work-schedule records all help substantiate your hours if ABOHN asks for support. Build the file before you apply rather than scrambling after the fact, especially if you have changed employers during the five-year window.
Education Alternatives and Approval
The standard pathway is the RN license plus 3,000 qualifying practice hours. The handbook also specifies education-based alternatives for candidates whose experience profile differs, but these require approval. In other words, you should not assume an alternative applies to you simply because your educational background seems relevant.
Key Takeaway
If you plan to rely on an education alternative rather than the full practice-hours pathway, contact ABOHN and confirm approval before you pay fees or schedule an exam. Verify the exact alternatives and their documentation requirements in the March 2026 handbook.
Because alternatives are approval-based, timing matters. Build in extra weeks if you expect to submit transcripts or other supporting material, and keep copies of everything you send.
Application and Fee Mechanics
The fee structure is straightforward, and it is worth understanding how the two charges differ:
- $150 application fee covers the review of your eligibility.
- $400 examination fee covers the exam itself.
- $550 total is the figure to budget for your first attempt.
For a complete budget that also accounts for study materials and downstream costs, read our COHN certification cost breakdown. Employers frequently reimburse certification costs, so ask your occupational health or HR leadership before paying out of pocket.
Registering through ASC
Exam delivery is handled by Assessment Systems Corporation (ASC). Once ABOHN approves your eligibility, you schedule through ASC and choose between two delivery modes:
- Test center: a proctored in-person environment.
- MonitorEDU live remote: a live-proctored online option you take from an approved location.
If you choose remote delivery, treat the technical and environment requirements as seriously as the exam content. Check your equipment, internet connection, and room setup well in advance. For scheduling windows and deadlines, see COHN exam dates, testing windows, and scheduling.
What You Qualify to Sit For
Understanding the exam itself helps you decide when you are truly ready to apply. The COHN exam consists of 160 multiple-choice questions delivered in 3 hours. Of those, 135 are scored and 25 are pretest items used to evaluate future questions. You will not be told which questions are pretest, so every question deserves your full effort. The exam is closed-book.
| Domain | Scored Items |
|---|---|
| Clinical Practice and Case Management | 72 |
| Risk and Compliance | 40 |
| Program Management and Quality Assurance | 23 |
Note that these figures are the official scored-item allocation (72, 40, and 23 across the three domains, totaling 135), not percentage labels. Clinical Practice and Case Management is the largest domain by a wide margin, which tracks with the fact that most occupational health nurses spend the bulk of their time on clinical and case-management work.
The passing standard is Angoff-based, meaning it is set by expert judgment about what a minimally competent certified nurse should know rather than by grading on a curve. For a deeper look at how the standard is set, see our page on the COHN passing score, and for what published outcomes suggest, see the COHN pass rate analysis.
Matching Your Experience to the Exam Domains
Meeting the eligibility threshold means you may sit for the exam; it does not mean you are ready. Because your qualifying hours may be concentrated in one part of the profession, a candid inventory is the smartest first step after your application is accepted.
Domain 1: Clinical Practice and Case Management
The largest slice of the exam. Candidates with strong clinic or injury-management backgrounds usually feel at home here, but should still review case-management frameworks and return-to-work reasoning.
- Assessment and triage of work-related injury and illness
- Workers' compensation case management and disability management
- Return-to-work, modified duty, and fitness-for-duty concepts
- Medical surveillance and health screening
Domain 2: Risk and Compliance
Often the area where clinic-focused nurses discover gaps. Expect scenarios that require connecting a workplace hazard to the right regulatory or programmatic response.
- Hazard identification and exposure assessment
- Regulatory standards and recordkeeping obligations
- Surveillance programs and medical monitoring
- Legal and ethical considerations in occupational health practice
Domain 3: Program Management and Quality Assurance
The smallest domain, but the one where nurses without management exposure can lose points. Focus on how programs are planned, measured, and improved.
- Program planning, implementation, and evaluation
- Quality improvement and outcome measurement
- Resource, budget, and stakeholder management
- Health promotion and wellness program design
Once you know where your experience is thin, our COHN study guide shows how to build a preparation plan around those gaps, and the COHN difficulty guide helps you calibrate expectations. You can also test yourself with realistic questions on the COHN practice test site.
A Qualification Timeline for Your Application
Because eligibility is documentation-driven, a short, front-loaded timeline works better than a long study-first approach. Here is a COHN-specific sequence for the weeks surrounding your application:
Verify eligibility
- Download the March 2026 handbook and read the eligibility section carefully
- Confirm your RN license is active and your name matches your ID
- Calculate your occupational-health hours within the last five years
Gather documentation
- Collect supervisor verification and job descriptions
- If using an education alternative, request approval and assemble transcripts
- Confirm whether your employer will reimburse the $550 total
Apply and plan content review
- Submit the application and $150 fee
- Begin with Clinical Practice and Case Management (72 scored items) since it carries the most weight
- Pay the $400 examination fee once approved and schedule through ASC
Close domain gaps
- Schedule extra review time for Risk and Compliance if your background is clinic-heavy
- Add Program Management and Quality Assurance practice if you lack management exposure
- Decide between test center and MonitorEDU remote delivery
Requirements After You Pass
Qualifying is not a one-time event. COHN is a five-year certification, and maintaining it has its own requirements. For recertification, ABOHN expects:
- Active RN status
- 3,000 practice hours
- 50 related continuing nursing education (CNE) hours
There is also an annual maintenance/recertification fee of $150. Tracking your CNE and practice hours from the day you pass saves considerable stress five years later. Because recertification mirrors the same practice-hours logic as initial eligibility, nurses who stay in occupational health roles generally find it manageable. To understand the earning side of keeping the credential, see the COHN salary guide, and for the types of roles that value it, see COHN jobs.
Common Eligibility Pitfalls
Counting hours outside the window
The most frequent mistake is including experience from outside the previous five years. If a large portion of your occupational-health history is older, recalculate with only the recent window.
Assuming related experience counts
General nursing, emergency room, or public-health work may feel adjacent to occupational health, but eligibility turns on occupational-health practice specifically. Review the handbook's definition and, if your role is hybrid, document the occupational-health portion clearly.
Skipping approval for alternatives
Education alternatives require approval. Applying without it, or assuming it will be granted, can cost time and money.
Using outdated information
Fees, formats, and policies change. Always verify against the current handbook, fee schedule, and certification statistics published by ABOHN. One note of caution on statistics: ABOHN reports a 65% pass figure for 2025, yet the published statistics also list 57 and 85 in a way that remains an unresolved discrepancy. Treat any single number with care and see our pass rate discussion for context.
Frequently Asked Questions
Candidates need an RN license or international equivalent plus 3,000 occupational-health practice hours within the previous five years. Specified education alternatives exist, but they require approval from ABOHN before you apply.
The initial cost is $550: a $150 application fee and a $400 examination fee. After certification, there is a $150 annual maintenance/recertification fee. See our certification cost guide for a broader budget.
Yes. The 3,000 occupational-health practice hours must fall within the previous five years. Older experience outside that window does not count toward the requirement, so recalculate based only on recent practice.
It is a closed-book, 3-hour exam with 160 multiple-choice questions, of which 135 are scored and 25 are pretest. It is delivered through ASC at a test center or via MonitorEDU live remote proctoring.
COHN recertification occurs every five years and requires active RN status, 3,000 practice hours, and 50 related CNE hours, along with the $150 annual maintenance/recertification fee. Track your hours and education from the start.
Meeting the COHN requirements is mostly a matter of careful documentation: confirm your license, count your recent occupational-health hours, check whether an education alternative needs approval, and budget the $550 total. Once you are cleared to test, focus your preparation on the three domains, starting with the heavily weighted Clinical Practice and Case Management content. For realistic practice as you prepare, visit the COHN Exam Prep practice tests.