What do I need to sit Grade 3?

MT Grade 2 in good standing. 4 years of experience, or 3 years with a bachelor's or water/wastewater associate degree.

How is the Grade 3 exam weighted?

Inspection, Maintenance, Installation and Repair 28%; Tools and Equipment 18%; Records, Reports and supervisory control and data acquisition (SCADA) 13%; Safety 18%; Administration and Communication 12%; Math 11%.

What score do I need to pass Grade 3?

There is no fixed percentage. CWEA sets the pass point for each exam form by the Modified Angoff method, so it varies with the difficulty of the form. The exam is 100 points in 3 hours.

CWEA Mechanical Technologist Grade 3 Practice Test

Administered by California Water Environment Association (CWEA)

At Grade 3 the largest block is Inspection, Maintenance, Installation and Repair (28% of the exam).

For the technicians who keep pumps, blowers, motors, drives and mechanical plant equipment running.

Start studying Grade 3

Official formula sheet

Formula sheet (in the CWEA candidate handbook) (opens in a new tab)California Water Environment Association (CWEA) · Shown onscreen during the exam.

Grade 3 eligibility

To sit the Grade 3 exam

Mechanical Technologist (MT) Grade 2 in good standing.
4 years of experience, or 3 years with a bachelor's or water/wastewater associate degree.

Related outside-industry experience can count for up to half at Grade 2 and up to a quarter at Grades 3 and 4.

How Grade 3 is weighted

Content area	% of the exam
Inspection, Maintenance, Installation and Repair	28
Tools and Equipment	18
Records, Reports and SCADA	13
Safety	18
Administration and Communication	12
Math	11

Grade 3 exam format

Format: computer-based multiple choice through Pearson VUE, at a test center or online proctored
Length: 3 hours, 100 points
Pass score: not a fixed percentage; CWEA sets it for each exam form by the Modified Angoff method
Scheduling: four exam windows per year, each with an application deadline

Grade 3 sample question

Records and reports: reliability · an original practice item written only from publicly available sources, not a real exam question

Maintenance records show a pump failed 6 times in 18,000 run hours. What is its mean time between failures (MTBF)?

0.00033 h
3,000 h
18,000 h
108,000 h

Answer and working

B. 3,000 h

MTBF = operating hours ÷ number of failures = 18,000 ÷ 6 = 3,000 hours. 0.00033 is the failure rate (failures per hour), the inverse of MTBF; 18,000 is the total run time with the failures ignored; 108,000 multiplies instead of dividing.

Grade 3 questions answered

What do I need to sit Grade 3?: MT Grade 2 in good standing. 4 years of experience, or 3 years with a bachelor's or water/wastewater associate degree.
How is the Grade 3 exam weighted?: Inspection, Maintenance, Installation and Repair 28%; Tools and Equipment 18%; Records, Reports and supervisory control and data acquisition (SCADA) 13%; Safety 18%; Administration and Communication 12%; Math 11%.
What score do I need to pass Grade 3?: There is no fixed percentage. CWEA sets the pass point for each exam form by the Modified Angoff method, so it varies with the difficulty of the form. The exam is 100 points in 3 hours.

What this exam covers

Inspection, Maintenance & Repair
Tools & Equipment
Records, Reports & SCADA
Mechanical Safety
Administration & Communication
Math for Mechanics

How to study for it here

Practice quizzes — filter to any topic above and work through it with explanations.
Flashcards — spaced repetition over terms, formulas and regulations.
Mock exam — a timed run at this grade.
Official formula sheet — a link to the sheet the certifying body publishes for this exam, where it publishes one, so you study from the real thing.

Free, no account, and progress stays in your browser.

Other grades in this track

Grade 1 · Grade 2 · Grade 4 · All Mechanical Technologist grades

Sources

MT Candidate Handbook, CWEA (effective May 2026 (2021 blueprint))

Topic coverage follows Mechanical Technologist Candidate Handbook, Version 2026.01 (California Water Environment Association, effective May 2026). Practice questions are written only from publicly available sources (that outline and the regulations and references it cites); they are not real exam questions, which are confidential. Check current application requirements, fees and exam dates on the certifying body's own page: official certification page.

Questions, flashcards, and explanations are AI-written from publicly available sources only: the exam content outlines and candidate materials each certifying body publishes without restriction, and the regulations and technical references they cite. No confidential material is used, including actual exam questions, recollections of any exam sat by the author, or any handbook or document released under a confidentiality agreement. Content is then put through repeated review — regulatory values checked against primary sources, every calculation recomputed, and errors corrected — plus spot checks by the author, who holds California water operator certifications and a California civil engineering licence. Those spot checks are sampling, not a professional review: nothing here is stamped, sealed, or offered as engineering advice, and not every item has been individually verified, so mistakes can still slip through.