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FAQ about the specialist certification

What do I need to study in order to pass the specialist exam?

There are 100 questions (single choice, multiple choices or true/false) for the specialist exam. The exam is based on the materials of WFI training courses. If you study the course material properly, you should have no problem passing the exam. We also recommend that you have at least one year of field experience in the air/liquid filtration & separation industry. WFI does offer both online live courses and course recordings to help you study.

Can I check references during the exam?

Yes, you are allowed to refer to course handouts and references during the exam. However, please note that you are not permitted to communicate with or connect to others while taking the exam.

What is the minimum score required to obtain the specialist certification?

To obtain the specialist certification, applicants must achieve a passing grade of 70% or higher on the Specialist Examination. This score threshold ensures qualification for receiving the specialist certificate.


What is the cost to take the exam?

Testing fees are included in the specialist registration fee for applicants.

If the applicant fails to pass the exam, and a re-take is necessary, there will not be any fee charged to re-take the exam. There is no fee to renew certification for each renewable cycle.


What are the renewal requirements?

To maintain CFSS Certification, you must complete four  (4) continuing education credits (CEC) annually from the categories listed below.

4 Credits:

  • Attended WFI Courses

  • Attended WFI Educational Webinars

  • Attended WFI Annual Conference

  • Attended seminar on air/liquid filtration & separation given by a related association or organization (such as ASHRAE, FILTECH, EPA, AIChE, AFS, INDA, TFS, or equivalent)

  • Attended and passed a college-level course on air/liquid filtration & separation

  • Published in a well established journal, conference proceeding or magazine related to air/liquid filtration & separation

  • Attended training seminar related to air/liquid filtration & separation given by a supplier/manufacturer of air/liquid filtration & separation related products


When / Where can I take the exam next?

  • The upcoming CFSS Exam will be conducted online once a year on November 1st from 8:00 AM to 10:00 AM EST in 2023. Please note that it is mandatory to have your camera turned on during the exam.

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