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Frequently Asked Questions

1. How are drinking water treatment facilities classified in Illinois?

  • Class A - Water treatment facilities that include coagulation/sedimentation, lime softening, UV disinfection, pathogen removal/inactivation, and/or membrane filtration
  • Class B - Water treatment facilities that include aeration and filtration, filtration (other than membrane filtration), and/or ion exchange
  • Class C - Water treatment facilities that utilize chemical feed only
  • Class D - Water treatment facilities limited to pumpage, storage, or distribution

2. What are the drinking water operator certification levels and eligibility requirements for each level?

Each certification level requires a passing score of 70% or higher on the corresponding examination, graduation from high school or equivalent, and the following experience:

  • Class A - 5340 hours of experience in a Class A water supply operation
  • Class B - 5340 hours of experience in a Class B water supply operation
  • Class C - 1780 hours of experience in a Class C water supply operation
  • Class D - 890 hours of experience in a Class D water supply operation

3. What is the first step in becoming a certified drinking water supply operator?

You must complete and submit "Drinking Water Operator Certification Examination Request" with a check or money order for $10.00. If approved, you will receive a Letter of Admission from the Illinois EPA along with an exam schedule and instructions for reserving a seat for the exam. Once you pass the examination, you will become an Operator in Training (OIT).

4. Where and how do I take the exam?

Exams are offered at the following locations: Champaign, Edwardsville, Elgin, Marion, Rockford, and Springfield. You will need to reserve a seat at least one week in advance of the exam by calling the desired examination center. You must bring photo identification, a non-programable calculator, and the Illinois EPA Letter of Admission with you on the day of the exam. Cell phones and other electronic devices are not permitted in the testing center.

5. What happens after the exam?

Examination results will be mailed to you. If you pass the exam, you will receive a congratulatory letter with a wallet card confirming your Operator in Training status. An Operator in Training certificate is valid for six years. If, within this time frame, you meet the eligibility requirements for full certification, you can then complete and submit an Application for Certification along with the $30 application review fee. If you fail the exam, you may re-test. To re-test, complete and submit a new Drinking Water Operator Certification Examination Request with a check or money order for $10.00. After the request is received and processed, the Illinois EPA will send you a Letter of Admission to test again. For each exam level, you are limited to testing four times in a single year. You must pay the $10.00 fee and receive a new exam Letter of Admission for each exam attempt.

6. What is an Operator in Training?

An Operator in Training (OIT) is the first step to becoming a fully certified drinking water operator in Illinois. An OIT has passed one of the exams for drinking water operator certification. An OIT may or may not have met the requirement for all of the experience at the time they passed the exam. An OIT certificate is valid for a period of six years. Renewal training is not required in order to maintain an OIT certificate. There is no renewal for an OIT certificate. If the OIT has not successfully completed the experience requirements for the certificate they seek and submitted a full application for certification, the OIT certificate will expire and the person will have to retest. An OIT is not fully certified and cannot act as a Responsible Operator in Charge at any facility.

7. How do I become a certified drinking water supply operator?

Once you have passed the examination, you may be eligible for full certification. Each application packet includes instructions and an experience worksheet. Carefully read the instructions and complete the experience worksheet for the level of certification desired. Once you have acquired the required amount of experience, complete and submit the application for certification along with the $30 application review fee. In addition to documenting your hands-on experience, your application must include three references who can verify your character and experience and a letter of verification prepared by a water supply official. If you wish to receive credit for any educational experience, your application must include copies of transcripts and/or course completion certificates. Your Operator in Training status is valid for six years. If you do not meet the certification requirements in this time frame, you must re-test before you can become a certified operator.

8. What happens when my certificate is up for renewal?

Drinking water operator certificates shall be issued for a period of three years, with the expiration date being three years from the first day of July of the calendar year in which the certificate is issued or renewed. During the three-year renewal period, you are required to complete drinking water related training. Class A and Class B Operators are required to complete 30 renewal training hours. Class C and Class D Operators are required to complete 15 renewal training hours. A "Certificate Renewal Application" will be sent about four months before your expiration date. To renew your certificate, complete the Renewal Application and submit it with a check or money order for $10.00. In addition, we must have a record of the required training. The Renewal Training Hours must be completed and submitted to the Agency prior to the July 1 expiration date. Operators shall submit the training hours completed to the Agency electronically through the Agency's Operator Certification database or by submitting the Operator Training Submission Form. You may submit the form at any time during the renewal period. You may not carry over training hours into your next renewal period, and training completed outside of your renewal period will not count toward your certificate renewal.

9. What type of training is acceptable for renewal training?

All training courses must get pre-approval from the Illinois EPA. Renewal training must directly relate to water distribution, water treatment or the professional responsibilities of the operator. To be sure that a training event is acceptable, you may want to ask the training provider before any fees are paid. There are training providers that offer courses through correspondence, on-line and CD-ROM, not to mention the training providers that have day and night classes and those that will come to you for training. A minimum of 2/3 of the total renewal training requirements must relate to the technical aspects of water treatment and distribution. No more than 1/3 of the total renewal training hours required may be comprised of non-technical aspects such as computer workshops, first aid, and safety. Renewal training credit for a course will only be given once during the three-year renewal period. Training that is not acceptable for Renewal Training includes personal self-improvement courses, plant tours, travel time to and from a training event, on-the-job work or apprenticeships, and portions of meetings when drinking water related training is not provided (i.e. lunches, breaks, etc.).

10. What if I don't complete the required training before my expiration date?

Operators who do not meet the renewal training requirements by their certificate’s expiration date have up to two years to get the training completed. However, once the certificate expiration date passes, your certification will no longer be valid in Illinois and will remain expired until the training is completed and a certificate is restored by the Illinois EPA.

11. What if I completed the training but failed to send it in on time?

If you met the training requirement during the renewal period, but are late mailing in the renewal application and/or any training documents, you will have to submit the required documents and $20.00 ($10.00 renewal fee and $10.00 restoration fee) to restore your certificate. This must be done within two years of the expiration date of your certificate.

12. Proof of Training Records, Record Keeping, Audits:

Certified water supply operators are required to maintain their own proof of training records for a period of six years. The Illinois EPA may audit proof of training records by random selection or in cases where additional information is required. Failure to provide proof of training documentation when specifically requested by the Illinois EPA may result in certificate revocation or denial of certificate renewal/restoration. Proof of training must include records showing the training name, Illinois EPA course identification number, name of training provider, course instructor, date, location, and total training hours received.

For more detailed information related to Operator Certification, please see