These handbooks provide information needed to apply and prepare for the COHN and COHN-S examinations. Please click on the images to download the handbooks.

Each handbook includes the following: eligibility requirements, examination policies, examination application, test blueprint, core content areas, sample questions, and study references. Please retain this handbook after applying for the examination. It is extremely useful when studying for the examination.

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 qualifications.  Please review the examinations Blue Prints/Test Specifications in BOTH HANDBOOKS before deciding on which examination to take.  It is HIGHLY RECOMMENDED that you choose the examination that fits your practice, not your level of education.

All of ABOHN examinations are developed with our testing agency and a panel of ABOHN Board Certified subject matter experts (SMEs). The Practice Analysis Advisory Committee surveys a broad range of OHNs and this document in turn runs the development of testing items. The updated exams are given to a separate panel of judges (Standard Setting Committee). These judges participate in a standard setting study (cut score) that consists of the following three major steps:

1. Definition of Minimum Competence

2. Rating of Examination Items

3. Consideration of Empirical Data

These Handbooks (REV 1/2024) will be in effect until 7/31/2024.

If you are planning to take the COHN or COHN-S after 7/31/2024 - Please see the front page of the website for updates.

COHN Cover 0124

COHN-S Cover 0124



What are some suggestions to prepare for the certification exam?

< Recently certified occupational health nurses (OHN) identified these tips to prepare for the exam: 

  • Begin a regular study plan about 6 months prior to when you plan to take the exam.
  • >Studied 3-5 days a week for an average of 9-10 hours weekly.
  • The OHNs found helpful materials included:
    • AAOHN Core Curriculum.
    • ABOHN Exam Blueprints.
    • ABOHN Self-Assessment Tests (CSATs)
  • 44% indicated a certification review course was helpful

Please note:  Although the AAOHN Core Curriculum and on-line classes provide an excellent review of the aspects of OHN practice, it is not intended as an exclusive source of information for the exams.

Although ABOHN cannot endorse nor recommend any specific course(s) for preparation, we can provide industry information that may help you in studying for the COHN and/or COHN-S: