- How the COHN Exam Blueprint Works
- The 72/40/23 Scored-Item Allocation
- Domain 1: Clinical Practice and Case Management
- Domain 2: Risk and Compliance
- Domain 3: Program Management and Quality Assurance
- What the Questions Look Like
- Eligibility, Fees and Delivery
- Sequencing Your Study Around the Domains
- Where Domain Knowledge Shows Up on the Job
- Frequently Asked Questions
- The Certified Occupational Health Nurse exam covers three domains: Clinical Practice and Case Management, Risk and Compliance, and Program Management and...
- Scored items are allocated 72/40/23 across the domains, as item counts rather than percentage labels.
- The exam has 160 multiple-choice questions: 135 scored and 25 unscored pretest items, over 3 hours.
- Clinical Practice and Case Management is the largest domain, so it deserves the biggest share of your study time.
How the COHN Exam Blueprint Works
The Certified Occupational Health Nurse (COHN) credential is administered by the American Board for Occupational Health Nurses, Inc. (ABOHN), with testing delivered through Assessment Systems Corporation (ASC) at test centers or via MonitorEDU live remote proctoring. The exam is built on a content outline that divides the occupational health nursing role into three domains. Understanding how those domains are weighted, and what each one really asks of you, is the single most efficient way to organize your preparation.
If you are new to the credential itself, our explainers on what COHN certification is and what COHN stands for cover the basics. This guide goes deeper on the exam's structure: what each domain contains, how the items are distributed, and how to translate that into a study plan. For a broader preparation roadmap, pair it with the COHN study guide.
The three domains, in the order ABOHN lists them, are:
- Clinical Practice and Case Management
- Risk and Compliance
- Program Management and Quality Assurance
Notice the framing. This is not a general nursing exam with an occupational flavor. The domains reflect how an occupational health nurse actually operates inside an employer: treating and managing worker health problems, controlling workplace hazards and meeting legal obligations, and running the health program as a business function with measurable outcomes.
The 72/40/23 Scored-Item Allocation
Here is a detail many candidates get wrong. The official allocation of scored items across the three listed domains is expressed as item counts: 72, 40 and 23. These are not percentage labels, and you should be cautious about any third-party resource that converts them into rounded percentages without showing the math. The scored items total 135, and the 25 pretest items sit on top of that to make the 160-question exam.
| Domain | Scored Items | Relative Emphasis |
|---|---|---|
| Clinical Practice and Case Management | 72 | Largest domain by a wide margin |
| Risk and Compliance | 40 | Second largest |
| Program Management and Quality Assurance | 23 | Smallest, but still a meaningful block |
Two practical consequences follow. First, Clinical Practice and Case Management accounts for more scored questions than the other two domains combined by a margin of nine items, so a weak performance there is very hard to offset. Second, you cannot identify which 25 items are the unscored pretest questions while testing, so every question deserves your full effort.
Domain 1: Clinical Practice and Case Management
This is the heart of the exam and the largest slice of scored items. It tests whether you can assess, treat, refer and manage the health of a working population, and coordinate care when an injury or illness affects someone's ability to work.
Clinical Practice and Case Management (72 scored items)
Expect scenario-driven questions that ask what the occupational health nurse should do first, next, or not at all.
- Assessment and triage of work-related injuries and illnesses, including prioritization when several workers present at once
- Case management from injury through return to work, including coordination with treating providers, supervisors and claims administrators
- Fitness-for-duty, pre-placement and return-to-work evaluations, and how job demands shape clinical decisions
- Medical surveillance and health screening tied to specific exposures
- Health promotion and chronic condition management in the workforce
- Emergency response and first-aid-level decision making at the worksite
- Documentation, confidentiality and the boundary between clinical information and employer information
What makes this domain distinctive
The clinical content is filtered through a workplace lens. A question about a back injury is rarely only about the back; it is about modified duty options, work restrictions, communication with the employer, and what information the nurse may and may not share. Candidates from bedside backgrounds sometimes stumble because their instinct is to treat, while the exam often rewards the answer that protects the worker's privacy, keeps the case moving toward safe return to work, and respects scope of practice.
Case management deserves special attention because it is named in the domain title itself. Be ready to reason about the full arc of a case: initial evaluation, treatment coordination, restrictions, follow-up, closure. If you want to see how these skills translate into positions, our overview of COHN jobs shows where this work happens.
Domain 2: Risk and Compliance
With 40 scored items, this domain covers the regulatory and hazard-control side of occupational health nursing. It is where the discipline's identity as a population-and-workplace specialty is clearest.
Risk and Compliance (40 scored items)
Questions here test whether you can recognize hazards, apply the right control logic, and keep the organization within the law.
- Workplace hazard categories: chemical, physical, biological, ergonomic and psychosocial
- The hierarchy of controls and how a health professional supports engineering, administrative and personal protective equipment decisions
- Exposure assessment, surveillance and the role of the nurse alongside industrial hygiene and safety colleagues
- Recordkeeping and reporting obligations for work-related injuries and illnesses
- Workers' compensation concepts and how they intersect with clinical documentation
- Disability, accommodation and privacy considerations when health information touches employment decisions
- Ethics, including conflicts that arise when employer and employee interests diverge
Thinking like a compliance-minded clinician
The distinguishing skill here is knowing which question you are really being asked. Some items are about prevention (what control reduces exposure at the source), some are about obligation (what must be recorded or reported), and some are about ethics (what the nurse should do when a request conflicts with confidentiality). Practicing the habit of naming the category before you read the answer choices will sharpen your accuracy considerably.
Domain 3: Program Management and Quality Assurance
The smallest domain at 23 scored items is nonetheless where many experienced clinicians feel least prepared, because it is about running a program rather than treating a patient.
Program Management and Quality Assurance (23 scored items)
This domain treats the occupational health service as an organizational function that must plan, budget, measure and improve.
- Needs assessment using workforce health data, injury trends and exposure information
- Program planning, goal setting and prioritization with limited resources
- Policies, procedures and standing orders that govern nursing practice at the worksite
- Evaluation of program outcomes and the use of metrics to demonstrate value to leadership
- Quality improvement cycles and how findings drive changes in practice
- Budgeting, vendor and contract considerations, and communication with management
- Collaboration with safety, human resources, legal and external providers
Why the small domain still decides close results
Twenty-three items is not trivial. Because this content is less familiar to clinicians, it is also where careful preparation produces the quickest gains. Many candidates over-invest in clinical review because it feels comfortable and then lose points on questions about program evaluation or quality improvement. Treat this domain as a place where modest, focused study pays off disproportionately.
What the Questions Look Like
The exam is composed of 160 multiple-choice questions, of which 135 are scored and 25 are pretest items used to evaluate future questions. You have 3 hours, and the exam is closed-book. Pass or fail is determined using an Angoff-based passing standard, a criterion-referenced method in which subject-matter experts judge how a minimally competent candidate would perform on each item.
Rather than testing isolated facts, most items present a short workplace scenario and ask for the best action, the most appropriate nursing judgment, or the priority consideration. Expect to eliminate two plausible-looking options and choose between two that are both defensible, with the deciding factor being scope, sequence or confidentiality.
Eligibility, Fees and Delivery
Before you can sit for the exam you must meet eligibility rules and complete the application process. The core requirement is an RN license (or international equivalent) plus 3,000 hours of occupational health practice within the previous five years. Specified education alternatives exist but require approval. Full detail is in our guide to COHN requirements.
| Item | Detail |
|---|---|
| Application fee | $150 |
| Examination fee | $400 |
| Total | $550 |
| Exam length | 160 multiple-choice questions, 3 hours |
| Scored vs. pretest | 135 scored, 25 pretest |
| Delivery | ASC test center or MonitorEDU live remote |
| Reference | March 2026 candidate handbook |
For budgeting beyond the exam fees, see the COHN certification cost breakdown, and check COHN exam dates for scheduling windows. Once you pass, certification is maintained on a five-year cycle that requires active RN status, 3,000 practice hours and 50 related CNE hours, along with a $150 annual maintenance/recertification fee.
Sequencing Your Study Around the Domains
Because the scored items are so unevenly distributed, your calendar should be too. The sample plan below shows one way to allocate time; adjust it to your own strengths and the weeks you have before your test date.
Clinical Practice and Case Management
- Spend the largest block here: 72 scored items sit in this domain
- Drill return-to-work and fitness-for-duty scenarios and the case management lifecycle
- Review confidentiality boundaries between clinical and employer information
Risk and Compliance
- Organize hazards by category and map each to the hierarchy of controls
- Practice distinguishing prevention, obligation and ethics questions
- Review recordkeeping and workers' compensation intersections with documentation
Program Management and Quality Assurance
- Learn program planning, evaluation metrics and quality improvement cycles
- Work through needs-assessment scenarios using workforce data
Integrated Review
- Take timed mixed-domain sets to practice pacing across 160 items in 3 hours
- Revisit your weakest domain using the COHN cheat sheet for rapid recall
To pressure-test each domain, work through questions on the COHN practice test site, which lets you see where your weak spots actually are rather than where you assume they are. If you are wondering how demanding all this will feel, our difficulty guide sets realistic expectations.
Key Takeaway
Allocate study time roughly in proportion to the 72/40/23 scored-item split, then adjust for your own background. Bedside nurses usually need extra time on Domain 3, while those from program-management roles often need more clinical case-management practice.
Where Domain Knowledge Shows Up on the Job
The three domains map neatly onto real employment settings. Manufacturing plants, utilities, healthcare systems, logistics operations, government agencies and large corporate campuses all employ occupational health nurses, and the mix of domain skills differs by setting. A nurse running an onsite clinic leans heavily on Domain 1, a nurse embedded in a safety and compliance team leans on Domain 2, and a nurse who directs an employee health department spends much of the day in Domain 3.
That variety is part of why the certification carries weight with employers and why many candidates ask whether it pays off. Our analyses of the COHN salary picture and the value of the credential examine that question without relying on inflated claims. If you are still orienting yourself, what a COHN does is a good starting point.
Frequently Asked Questions
There are three: Clinical Practice and Case Management, Risk and Compliance, and Program Management and Quality Assurance. Scored items are allocated 72, 40 and 23 across them respectively.
Clinical Practice and Case Management is the largest, with 72 of the 135 scored items. It therefore deserves the greatest share of your preparation time.
No. They are official scored-item allocations, not percentage labels. Together they total the 135 scored questions, and the exam adds 25 unscored pretest items for a 160-question test.
No. The exam is closed-book. You will answer 160 multiple-choice questions in 3 hours, either at an ASC test center or through MonitorEDU live remote delivery.
The application fee is $150 and the examination fee is $400, for a total of $550. Recertification every five years also carries an annual maintenance/recertification fee of $150, so review the current ABOHN fee page before budgeting.
Mastering the blueprint is the foundation of a confident exam day. For the complete picture of the credential, revisit the COHN certification overview, then put your domain knowledge to work with timed practice questions at COHN Exam Prep.