The Ontario G2 gas technician exam, explained
How many questions, how long you get, what you need to pass and how the marks are split by module, so you know exactly what you’re walking into.
How many questions come from each module
This is the split on the real exam, taken from an actual G2 score report. Spend your study time where the marks are: Meters, Regulators & Valves alone is 20 questions, while Gas Refrigeration, Conversion Burners and Space Heating are only 5 each.
| Module | Topic | Questions | Share |
|---|---|---|---|
| M10 | Piping & Tubing | 15 | 9% |
| M11 | Electricity | 15 | 9% |
| M12 | Controls | 12 | 7% |
| M13 | Building Systems | 12 | 7% |
| M14 | Domestic Appliances | 8 | 5% |
| M15 | Meters, Regs & Valves | 20 | 12% |
| M16 | Dom. Gas Refrigeration | 5 | 3% |
| M17 | Conversion Burners | 5 | 3% |
| M18 | Water Heaters | 13 | 8% |
| M19 | Warm Air Systems | 10 | 6% |
| M20 | Hydronic Heat | 10 | 6% |
| M21 | Space Heating | 5 | 3% |
| M22 | Venting | 15 | 9% |
| M23 | Forced Air | 10 | 6% |
| M24 | Air Systems | 10 | 6% |
| Total | 165 | 100% | |
What exam day looks like
- You write on a computer at a Prometric test centre, after applying through TSSA.
- Every question is multiple choice. There’s no penalty for guessing, so never leave one blank.
- You get your pass or fail on screen at the end, with a score for each module.
- With 3.5 hours for 165 questions you have about 75 seconds each. Answer what you know, flag the hard ones, and come back.
How to study for it
- Find your weak modules first. Take a mixed test across all 15 modules so you know where you stand.
- Weight your time by the exam split. A module worth 20 questions deserves four times the attention of one worth 5.
- Drill the questions you get wrong until you get them right, and read why each answer is correct.
- Practise the math. Meter clocking, temperature rise, pressure conversions and pipe sizing all show up. Our free gas tech calculators show the formulas.
- Sit a full timed practice exam of 165 questions in 3.5 hours before the real thing, and aim well above 75%.
Common questions
How many questions are on the G2 exam?
165 multiple-choice questions, split across the 15 G2 modules (M10 to M24). The table above shows how many come from each module.
How long is the G2 exam?
You get up to 3.5 hours. That works out to just over a minute per question, so there’s time to read carefully and look things up in your head, but not to get stuck on one question.
What mark do I need to pass?
75%. On a 165-question exam that means at least 124 correct answers.
Where do I write it?
The exam is delivered on a computer at a Prometric test centre. You apply through TSSA and then book your seat.
Do I get my result right away?
Yes. You see pass or fail at the end, with a score for every module. TSSA then sends an official result letter.
What happens if I fail?
Your score report shows how you did in each module, so you know exactly what to work on. You can’t apply for another attempt until TSSA officially issues your result, so use that time to drill your weakest modules.
Do I need my G3 first?
In Ontario, gas technicians normally progress from G3 to G2 to G1. Check TSSA’s current requirements for your situation before you apply.
Practise exactly like the real exam
Pass Your Gas has 785 exam-style questions, a timed 165-question exam split by module just like TSSA’s, and a readiness score that shows which modules are costing you marks.
Pass Your Gas is an independent study tool, not affiliated with TSSA or Prometric. Exam details can change; always check TSSA for the current requirements before you apply.