100+ Free OH Water/Wastewater Operator Practice Questions
Pass your Ohio Water and Wastewater Operator Certification exam on the first try — instant access, no signup required.
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About the OH Water/Wastewater Operator Exam
The Ohio water and wastewater operator certification exam covers OAC 3745-7, ORC Chapters 6109 and 6111, water treatment processes, wastewater treatment including activated sludge, distribution and collection systems, pump operations, laboratory testing, safety procedures, and math calculations.
Questions
100 scored questions
Time Limit
2-3 hours
Passing Score
70%
Exam Fee
$45 application fee + testing center fees (Ohio Environmental Protection Agency (Ohio EPA))
OH Water/Wastewater Operator Exam Content Outline
State Laws & Regulations
OAC 3745-7, ORC 6109/6111, certification classes, NPDES permits, and public notification
Water Treatment
Coagulation, flocculation, sedimentation, filtration, disinfection, and CT calculations
Wastewater Treatment
Activated sludge, sludge handling, BOD/TSS removal, and process control
Distribution & Collection
Pumps, hydraulics, cross-connection control, and collection system operations
Laboratory & Safety
Water quality testing, sampling procedures, record-keeping, and safety protocols
How to Pass the OH Water/Wastewater Operator Exam
What You Need to Know
- Passing score: 70%
- Exam length: 100 questions
- Time limit: 2-3 hours
- Exam fee: $45 application fee + testing center fees
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
Frequently Asked Questions
What certification classes does Ohio offer for water operators?
Ohio offers Class I, II, III, and Class A water supply certifications, plus corresponding wastewater (water reclamation) certifications. Operators can also hold OIT (Operator-in-Training) status after passing the exam but before completing experience requirements.
How do I schedule the Ohio water operator exam?
Ohio EPA exams are administered through Water Professionals International (WPI) via the PSI online portal at test-takers.psiexams.com/abc-oh. The application fee is $45 non-refundable.
Can training reduce the Ohio experience requirement?
Yes — completing OTCO or Cal State Sacramento approved correspondence courses reduces the experience requirement from 1,040 hours (or 3 years) to 520 hours (or 1 year).