Certificate of Qualification Sheet Metal Worker
(308A) Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. Which material is most commonly used for residential ductwork?
A. Stainless steel
B. Aluminum
C. Galvanized steel
D. Copper
Answer: C
Galvanized steel is durable, corrosion-resistant, and cost-effective
for duct systems.
2. What gauge number indicates thicker sheet metal?
A. 30
B. 28
C. 26
D. 24
Answer: D
Lower gauge numbers indicate thicker metal.
3. Which tool is primarily used to cut straight lines in sheet metal?
A. Aviation snips
B. Hand seamer
C. Folding bar
D. Rivet gun
, Answer: A
Aviation snips are designed for cutting sheet metal accurately.
4. What does S-cleat connect in duct installation?
A. Round ducts
B. Flexible ducts
C. Rectangular duct joints
D. Dampers
Answer: C
S-cleats are used to join rectangular duct sections.
5. What is the purpose of a drive cleat?
A. Seal air leaks
B. Hold duct corners together
C. Support vertical duct runs
D. Reduce vibration
Answer: B
Drive cleats lock duct sections into the S-cleats.
6. Which metal is most resistant to corrosion?
A. Mild steel
B. Aluminum
C. Galvanized steel
D. Stainless steel
Answer: D
Stainless steel has high corrosion resistance.
7. What layout tool is used to mark parallel lines?
A. Square
B. Divider
C. Compass
, D. Scriber
Answer: B
Dividers are used to mark equal spacing and parallel lines.
8. What fitting changes duct direction by 90 degrees?
A. Transition
B. Elbow
C. Tee
D. Offset
Answer: B
Elbows redirect airflow at angles.
9. What is the main function of duct insulation?
A. Increase airflow
B. Improve appearance
C. Reduce heat loss and noise
D. Prevent corrosion
Answer: C
Insulation helps control temperature and sound.
10. Which fastener is commonly used in sheet metal work?
A. Wood screw
B. Machine bolt
C. Sheet metal screw
D. Lag bolt
Answer: C
Sheet metal screws are designed for thin metals.
11. What does SMACNA stand for?
A. Sheet Metal Association of Canada
B. Sheet Metal and Air Conditioning Contractors’ National
(308A) Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
1. Which material is most commonly used for residential ductwork?
A. Stainless steel
B. Aluminum
C. Galvanized steel
D. Copper
Answer: C
Galvanized steel is durable, corrosion-resistant, and cost-effective
for duct systems.
2. What gauge number indicates thicker sheet metal?
A. 30
B. 28
C. 26
D. 24
Answer: D
Lower gauge numbers indicate thicker metal.
3. Which tool is primarily used to cut straight lines in sheet metal?
A. Aviation snips
B. Hand seamer
C. Folding bar
D. Rivet gun
, Answer: A
Aviation snips are designed for cutting sheet metal accurately.
4. What does S-cleat connect in duct installation?
A. Round ducts
B. Flexible ducts
C. Rectangular duct joints
D. Dampers
Answer: C
S-cleats are used to join rectangular duct sections.
5. What is the purpose of a drive cleat?
A. Seal air leaks
B. Hold duct corners together
C. Support vertical duct runs
D. Reduce vibration
Answer: B
Drive cleats lock duct sections into the S-cleats.
6. Which metal is most resistant to corrosion?
A. Mild steel
B. Aluminum
C. Galvanized steel
D. Stainless steel
Answer: D
Stainless steel has high corrosion resistance.
7. What layout tool is used to mark parallel lines?
A. Square
B. Divider
C. Compass
, D. Scriber
Answer: B
Dividers are used to mark equal spacing and parallel lines.
8. What fitting changes duct direction by 90 degrees?
A. Transition
B. Elbow
C. Tee
D. Offset
Answer: B
Elbows redirect airflow at angles.
9. What is the main function of duct insulation?
A. Increase airflow
B. Improve appearance
C. Reduce heat loss and noise
D. Prevent corrosion
Answer: C
Insulation helps control temperature and sound.
10. Which fastener is commonly used in sheet metal work?
A. Wood screw
B. Machine bolt
C. Sheet metal screw
D. Lag bolt
Answer: C
Sheet metal screws are designed for thin metals.
11. What does SMACNA stand for?
A. Sheet Metal Association of Canada
B. Sheet Metal and Air Conditioning Contractors’ National
