2025 Edition

Certified Occupational Health Nurse (COHN) Test Guide

The COHN Test Summary
What: An exam for nurses looking to receive prestige and recognition for their work in the field of occupational health nursing.
Who: U.S. registered nurses who have completed the required amount of working and continuing education hours are eligible to take the COHN exam.
Where: The COHN is offered at more than 150 testing sites across the U.S.
When: Tests are administered Monday-Friday throughout the year.
How: The COHN exam tests individuals on knowledge and experience in the field of occupational health nursing.
Type: Tests are computer based.
Why: COHN certification reinforces the special experience and knowledge that is required for occupational health nursing, in addition to providing professional pride and achievement.
Time: 3 hours
Language: English
Preparation: Online review courses and COHN exam prep books are useful study aids.
Cost: $350

By Jessica McNally, Tests.com

The Certified Occupational Health Nurse (COHN) exam, developed by the American Board for Occupational Health Nurses, Inc. (ABOHN) is a voluntary test available to registered nurses. COHN certification is recognized by peers as well as employers as a great achievement, and can lead to career advancement and employment opportunities in addition to professional prestige.

There are several requirements an applicant must meet prior to taking the COHN exam. An individual must be a licensed registered nurse (RN) and must be presently employed as an occupational health nurse for a minimum of eight hours a week. Additionally, an individual must have worked (over the past five years) at least 4000 hours as an occupational health nurse as well as a minimum of 50 contact hours in continuing education in the field of occupational health nursing.

The Test

If an individual meets all of the requirements, an application must be procured from, filled out, and returned to the ABOHN in order to be eligible to take the exam.

The COHN exam is comprised of 150 multiple choice questions categorized into the four divisions of occupational health nurses: Advisor, Clinician, Coordinator and Case Manager. Each of the four main categories is separated into subdivisions based on the four process steps in nursing: Planning, Assessment, Implementation and Evaluation.

In addition to these divisions and subdivisions, the ABOHN recognizes several areas of core content for the COHN exam. These include:

  • Biological Hazards
  • Chemical Hazards
  • Physical Hazards/Ergonomics
  • Safety and Industrial Hygiene Issues
  • Psychophysiological Hazards/Stress
  • Standards and Regulations
  • Disease Management
  • Emergency Response
  • Health Education/Promotion
  • Information Management/Record Keeping
  • Management Principles
  • Clinical Practice

Upon passing the examination, COHN certification is valid for five years.

If you need additional help preparing for the COHN, please see our COHN Directory to find helpful study aids.