Gas Technician 2 Exam Study Guide PDF
2026/2027 | Gas Systems, Safety, Codes
& Certification Review
SECTION 1: CSA B149.1 & B149.2 CODE APPLICATION
Question 1: According to CSA B149.1, what is the minimum size of a gas service
pipe supplying a single-family dwelling with natural gas?
A) 1/2 inch
B) 3/4 inch
C) 1 inch
D) 1-1/4 inches
Correct Answer: B
Rationale: CSA B149.1 requires the gas service pipe supplying a single-family dwelling
to be a minimum of 3/4 inch nominal pipe size to ensure adequate capacity and
pressure for typical residential loads .
Question 2: According to CSA B149.1, the maximum allowable pressure drop for a
natural gas piping system serving a residence is:
A) 0.5 inch water column
B) 1.0 inch water column
C) 2.0 inches water column
D) 0.5 psi
Correct Answer: B
Rationale: CSA B149.1 specifies a maximum pressure drop of 1.0 inch water column
(0.25 kPa) for natural gas piping systems serving residential and light commercial
applications .
,Question 3: A propane cylinder installed outdoors must be placed at least how
many feet from a building opening?
A) 3 feet
B) 5 feet
C) 10 feet
D) 15 feet
Correct Answer: B
Rationale: CSA B149.2 Clause 5.4.8 requires a minimum separation distance of 5 feet
from building openings (windows, doors, vents) for propane cylinders .
Question 4: According to CSA B149.1, the maximum gas pressure for a residential
appliance is typically:
A) 7 inches water column
B) 14 inches water column
C) 2 psi
D) 5 psi
Correct Answer: A
Rationale: CSA B149.1 limits the gas pressure to 7 inches water column (1.74 kPa) for
most residential natural gas appliances, with some exceptions .
Question 5: What is the minimum clearance required from combustible material
for a single-wall metal vent connector?
A) 6 inches
B) 9 inches
C) 12 inches
D) 18 inches
Correct Answer: C
Rationale: CSA B149.1 requires a minimum clearance of 12 inches from combustible
materials for single-wall metal vent connectors. Type B vent has a 1-inch clearance .
Question 6: Under CSA B149.1, which of the following is NOT a permitted material
for natural gas piping?
A) Black steel pipe
B) Copper tubing
C) Polyethylene pipe
D) PVC pipe
, Correct Answer: D
Rationale: PVC pipe is NOT permitted for gas piping under CSA B149.1. Black steel pipe,
copper tubing (underground), and polyethylene pipe (outside only) are permitted .
Question 7: A gas appliance with a draft hood must be vented to:
A) The attic
B) An unoccupied area
C) The outdoors
D) A crawlspace
Correct Answer: C
Rationale: CSA B149.1 requires that all gas appliances be vented to the outdoors to
safely remove combustion products .
Question 8: According to CSA B149.2, a propane tank must be equipped with a
pressure relief valve set to open at what percentage of the design pressure?
A) 80%
B) 100%
C) 120%
D) 150%
Correct Answer: C
Rationale: CSA B149.2 Clause 5.2 requires the pressure relief valve to be set to open at
120% of the design pressure .
Question 9: A branch gas line may be reduced in size from the main run only if:
A) The appliance is less than 10 feet away
B) The reduced section does not exceed the allowable pressure drop
C) The appliance is a water heater
D) The pipe is black steel
Correct Answer: B
Rationale: CSA B149.1 allows pipe sizing reductions as long as the system's pressure
drop remains within acceptable limits for all connected appliances .
Question 10: The maximum capacity of a gas pipe is determined by the pipe
diameter, length, and:
A) The type of gas
B) The specific gravity of the gas
2026/2027 | Gas Systems, Safety, Codes
& Certification Review
SECTION 1: CSA B149.1 & B149.2 CODE APPLICATION
Question 1: According to CSA B149.1, what is the minimum size of a gas service
pipe supplying a single-family dwelling with natural gas?
A) 1/2 inch
B) 3/4 inch
C) 1 inch
D) 1-1/4 inches
Correct Answer: B
Rationale: CSA B149.1 requires the gas service pipe supplying a single-family dwelling
to be a minimum of 3/4 inch nominal pipe size to ensure adequate capacity and
pressure for typical residential loads .
Question 2: According to CSA B149.1, the maximum allowable pressure drop for a
natural gas piping system serving a residence is:
A) 0.5 inch water column
B) 1.0 inch water column
C) 2.0 inches water column
D) 0.5 psi
Correct Answer: B
Rationale: CSA B149.1 specifies a maximum pressure drop of 1.0 inch water column
(0.25 kPa) for natural gas piping systems serving residential and light commercial
applications .
,Question 3: A propane cylinder installed outdoors must be placed at least how
many feet from a building opening?
A) 3 feet
B) 5 feet
C) 10 feet
D) 15 feet
Correct Answer: B
Rationale: CSA B149.2 Clause 5.4.8 requires a minimum separation distance of 5 feet
from building openings (windows, doors, vents) for propane cylinders .
Question 4: According to CSA B149.1, the maximum gas pressure for a residential
appliance is typically:
A) 7 inches water column
B) 14 inches water column
C) 2 psi
D) 5 psi
Correct Answer: A
Rationale: CSA B149.1 limits the gas pressure to 7 inches water column (1.74 kPa) for
most residential natural gas appliances, with some exceptions .
Question 5: What is the minimum clearance required from combustible material
for a single-wall metal vent connector?
A) 6 inches
B) 9 inches
C) 12 inches
D) 18 inches
Correct Answer: C
Rationale: CSA B149.1 requires a minimum clearance of 12 inches from combustible
materials for single-wall metal vent connectors. Type B vent has a 1-inch clearance .
Question 6: Under CSA B149.1, which of the following is NOT a permitted material
for natural gas piping?
A) Black steel pipe
B) Copper tubing
C) Polyethylene pipe
D) PVC pipe
, Correct Answer: D
Rationale: PVC pipe is NOT permitted for gas piping under CSA B149.1. Black steel pipe,
copper tubing (underground), and polyethylene pipe (outside only) are permitted .
Question 7: A gas appliance with a draft hood must be vented to:
A) The attic
B) An unoccupied area
C) The outdoors
D) A crawlspace
Correct Answer: C
Rationale: CSA B149.1 requires that all gas appliances be vented to the outdoors to
safely remove combustion products .
Question 8: According to CSA B149.2, a propane tank must be equipped with a
pressure relief valve set to open at what percentage of the design pressure?
A) 80%
B) 100%
C) 120%
D) 150%
Correct Answer: C
Rationale: CSA B149.2 Clause 5.2 requires the pressure relief valve to be set to open at
120% of the design pressure .
Question 9: A branch gas line may be reduced in size from the main run only if:
A) The appliance is less than 10 feet away
B) The reduced section does not exceed the allowable pressure drop
C) The appliance is a water heater
D) The pipe is black steel
Correct Answer: B
Rationale: CSA B149.1 allows pipe sizing reductions as long as the system's pressure
drop remains within acceptable limits for all connected appliances .
Question 10: The maximum capacity of a gas pipe is determined by the pipe
diameter, length, and:
A) The type of gas
B) The specific gravity of the gas
