Certification practice exams
Every exam includes free practice questions with explanations, topic-by-topic drills and timed mock exams.
5 exams
Commercial Driver's License (CDL) Knowledge Tests
Federal knowledge tests for Class A, Class B and Class C: General Knowledge, Air Brakes, Combination Vehicles, plus Hazmat, Tanker and Passenger endorsements.
- Questions
- 95questions
- Mock exams
- 6topics
- Difficulty
- Intermediatedifficulty
EPA 608 Technician Certification
Federal certification required to buy refrigerant and service stationary air-conditioning and refrigeration equipment. Covers Core, Type I, Type II and Type III.
- Questions
- 104questions
- Mock exams
- 4topics
- Difficulty
- Intermediatedifficulty
Wastewater Collection System Operator — Grade 1
Entry-level certification for operators who maintain sewers, manholes, and lift stations. Covers pipe materials, inspection and cleaning, lift station operation, infiltration and inflow, confined space safety, and the math behind pipe volume and slope.
- Questions
- 14questions
- Mock exams
- 5topics
- Difficulty
- Intermediatedifficulty
Wastewater Treatment Operator — Grade 1
Entry-level certification for operators of wastewater treatment plants. Covers preliminary and primary treatment, activated sludge basics, disinfection, lab sampling, safety, and the math behind flow, detention time, and chemical dosing.
- Questions
- 14questions
- Mock exams
- 5topics
- Difficulty
- Intermediatedifficulty
Water Treatment Operator — Grade 1
Entry-level certification for operators of drinking water treatment plants. Covers source water, coagulation and flocculation, sedimentation, filtration, disinfection, water quality rules, and the math behind dosing and detention time.
- Questions
- 14questions
- Mock exams
- 5topics
- Difficulty
- Intermediatedifficulty