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Ontario G3 Gas Technician exam preparation

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G3 Gas Code and Piping (B149.1): What's Tested and How to Study It

CSA B149.1 installation requirements, pipe materials, joints, supports and sizing.

Code questions are where well-prepared candidates lose marks, because the answers are specific and cannot be reasoned out. CSA B149.1 is the main reference for the G3 exam, and the questions tend to test whether you have actually read it.

What this topic covers

How to study it

Treat the numbers as the exam does — exactly. "NPS 2-1/2 and larger" is not approximately anything. Pipe sizing deserves its own session; it looks intimidating and is mechanical once the four steps are automatic.

The four-step pipe sizing method →

Sample questions

Five real questions from this topic, with the answers shown. The app holds 177 in this area alone, out of 1,184 across the whole syllabus.

How many inches of free conductor must be left at each outlet box for connections?

After appliance installation, what is the minimum time the gas pressure must be maintained during the low-pressure leak test?

In which code would you find the valve train requirements for a one-of-a-kind appliance requiring field approval?

When purging a gas piping system, which appliance should be purged first?

What is the maximum gas pressure allowed inside a one family dwelling?

Practise this topic free →

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