COHN / COHN-S Eligibility


You may only hold one Core Credential, either the COHN or the COHN-S, you cannot hold both credentials. (For example: If you are currently certified as a COHN and decide that you meet the COHN-S requirements and would like to hold the COHN-S, you must first pass the COHN-S examination and then give-up the COHN credential once your official COHN-S passing results are confirmed.)

Certified Occupational Health Nurse (COHN)

The COHN examination focuses on the OHN clinician practice.  The roles associated with the COHN credential are:  Clinician, Coordinator, Advisor and Case Manager.

Eligibility Requirements:

  • Current Active RN License
  • 3000 hours in occupational health nursing in the past five years; or

See handbook for alternatives to work experience.

Certified Occupational Health Nurse-Specialist (COHN-S)

The COHN-S examination focuses on the OHN with emphasis on administration in the workplace.  The roles associated with the COHN-S examination are: Clinician, Manager, Educator, Consultant and Case Manager.

Eligibility Requirements:

  • Current Active RN License
  • 3000 hours in occupational health nursing in the past five years
  • Bachelor Degree or higher (does not need to be in Nursing)

See handbook for alternatives to work experience.

PLEASE NOTE:  There are different education qualifications for the COHN and COHN-S examinations.  HOWEVER, if you qualify for both examinations, just having a higher degree does not necessarily mean you should take the examination with the higher degree qualification.  Both examination Blue Prints/Test Specifications can be found in each Handbook, and it is HIGHLY RECOMMENDED that you choose the examination that fits your practice, not your level of education.




After the eligibility requirements have been met, the candidate is required to achieve a passing score on the national examination.  Upon successful completion of the examination, a certificate is issued that states that the candidate has met the standards for board certification as a Certified Occupational Health Nurse or Certified Occupational Health Nurse-Specialist and either the COHN or COHN-S credentials are awarded.  Only those nurses who have met all of the criteria and have been successful on the examination and are in ACTIVE status are entitled to use these credentials.


To achieve COHN and COHN-S certification, eligible candidates must be successful on a 160-question, (135 scored and 25 pre-test) multiple choice, computer based examination.  The examinations are offered at 190 sites throughout the United States.   For a list of examination sites use this hyperlink   When you reach the site click on "Candidates," then click on "Healthcare" and then click on "American Board for Occupational Health Nurses."

Candidates have three hours to complete the examination.

The examination is developed and revised by the Board of Directors in consultation with a professional examination service.  Examination questions are written by a panel of certified occupational health nurses, are edited by experts in testing and evaluation and are approved by the Board.  The examination content is based on the results of research designed to identify the tasks and knowledge required to practice in the specialty of occupational health nursing.  This method has resulted in a valid and highly reliable examination.


Any candidate may request hand scoring of their examination.  The request must be made in writing to ABOHN within three months of the date of the examination and must be accompanied by the appropriate fee to cover the cost of the procedure.   Hand scoring is accomplished by the testing consultant and results are issued by them and copied to the ABOHN office.