G3 Piping and Tubing Systems 2

Question 1

What is the standard test pressure for new residential gas piping?

Accepted Answer

15 psi

Answer

The standard is 15 psi, well above normal operating pressure of about 0.25 psi.

Question 2

What type of pipe thread sealant is approved for gas connections?

Accepted Answer

Yellow Teflon tape or approved gas-rated pipe dope

Answer

Only sealants rated for gas service should be used, such as yellow Teflon tape.

Question 3

What is a drip leg (sediment trap) on a gas line?

Accepted Answer

Collects moisture, dirt, and debris before they reach appliance controls

Answer

A drip leg collects contaminants that could damage the gas valve.

Question 4

What is CSST and its special installation requirement?

Accepted Answer

Corrugated Stainless Steel Tubing; proper bonding/grounding

Answer

CSST is flexible gas piping requiring electrical bonding to protect against lightning.

Question 5

What is the minimum burial depth for underground gas piping in Ontario?

Accepted Answer

18 inches (450 mm)

Answer

CSA B149 requires 18 inches (450 mm) below finished grade.

G3 - Gas Technician Level 3 Certification Practice Test