New Mexico (NM) JSM Journeyman Sheet
Metal Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf
1. Which organization publishes the primary installation standards
commonly referenced for HVAC duct construction and sheet
metal fabrication?
A. OSHA
B. ASHRAE
C. SMACNA
D. EPA
Rationale: SMACNA (Sheet Metal and Air Conditioning Contractors'
National Association) develops widely accepted standards for HVAC
duct construction, fabrication, and installation. Journeyman sheet metal
workers frequently rely on SMACNA manuals for proper workmanship
and code compliance.
2. The primary purpose of a turning vane in a rectangular duct elbow
is to:
,A. Increase duct pressure
B. Reduce airflow velocity
C. Reduce turbulence and pressure loss
D. Eliminate balancing dampers
Rationale: Turning vanes guide air smoothly around duct elbows,
reducing turbulence, minimizing pressure losses, and improving
airflow efficiency.
3. Which gauge number represents the thicker sheet metal?
A. 30 gauge
B. 28 gauge
C. 18 gauge
D. 26 gauge
Rationale: As gauge numbers decrease, metal thickness increases.
Therefore, 18-gauge steel is significantly thicker than 26-, 28-, or 30-
gauge steel.
4. Before beginning hot work, what is typically required?
A. A completed timecard
B. A duct leakage report
C. A hot work permit
D. A balancing report
,Rationale: Hot work involving welding, brazing, or cutting requires a
hot work permit to ensure fire hazards are controlled and safety
precautions are implemented.
5. Which measuring tool provides the highest precision for
measuring sheet metal thickness?
A. Tape measure
B. Combination square
C. Micrometer
D. Chalk line
Rationale: A micrometer provides highly accurate measurements of
material thickness, making it ideal for verifying sheet metal gauges.
6. The purpose of duct insulation is primarily to:
A. Increase airflow
B. Reduce heat transfer and prevent condensation
C. Increase duct pressure
D. Reduce fan speed
Rationale: Insulation minimizes heat gain or loss while also preventing
condensation on cold ducts, improving system efficiency and
protecting building materials.
, 7. Which fastener is commonly used for joining light-gauge sheet
metal?
A. Lag screw
B. Carriage bolt
C. Pop rivet
D. Expansion anchor
Rationale: Blind (pop) rivets provide a strong mechanical connection
where access is available from only one side of the material.
8. A Pittsburgh seam is commonly used to:
A. Join copper tubing
B. Install duct insulation
C. Connect longitudinal edges of rectangular duct
D. Connect flexible duct
Rationale: The Pittsburgh seam is one of the most common
longitudinal duct seams because it provides strength and an airtight
joint.
9. OSHA requires fall protection in construction when workers are
exposed to falls of:
A. 4 feet
B. 6 feet
Metal Exam Questions and Correct Answers
(Verified Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf
1. Which organization publishes the primary installation standards
commonly referenced for HVAC duct construction and sheet
metal fabrication?
A. OSHA
B. ASHRAE
C. SMACNA
D. EPA
Rationale: SMACNA (Sheet Metal and Air Conditioning Contractors'
National Association) develops widely accepted standards for HVAC
duct construction, fabrication, and installation. Journeyman sheet metal
workers frequently rely on SMACNA manuals for proper workmanship
and code compliance.
2. The primary purpose of a turning vane in a rectangular duct elbow
is to:
,A. Increase duct pressure
B. Reduce airflow velocity
C. Reduce turbulence and pressure loss
D. Eliminate balancing dampers
Rationale: Turning vanes guide air smoothly around duct elbows,
reducing turbulence, minimizing pressure losses, and improving
airflow efficiency.
3. Which gauge number represents the thicker sheet metal?
A. 30 gauge
B. 28 gauge
C. 18 gauge
D. 26 gauge
Rationale: As gauge numbers decrease, metal thickness increases.
Therefore, 18-gauge steel is significantly thicker than 26-, 28-, or 30-
gauge steel.
4. Before beginning hot work, what is typically required?
A. A completed timecard
B. A duct leakage report
C. A hot work permit
D. A balancing report
,Rationale: Hot work involving welding, brazing, or cutting requires a
hot work permit to ensure fire hazards are controlled and safety
precautions are implemented.
5. Which measuring tool provides the highest precision for
measuring sheet metal thickness?
A. Tape measure
B. Combination square
C. Micrometer
D. Chalk line
Rationale: A micrometer provides highly accurate measurements of
material thickness, making it ideal for verifying sheet metal gauges.
6. The purpose of duct insulation is primarily to:
A. Increase airflow
B. Reduce heat transfer and prevent condensation
C. Increase duct pressure
D. Reduce fan speed
Rationale: Insulation minimizes heat gain or loss while also preventing
condensation on cold ducts, improving system efficiency and
protecting building materials.
, 7. Which fastener is commonly used for joining light-gauge sheet
metal?
A. Lag screw
B. Carriage bolt
C. Pop rivet
D. Expansion anchor
Rationale: Blind (pop) rivets provide a strong mechanical connection
where access is available from only one side of the material.
8. A Pittsburgh seam is commonly used to:
A. Join copper tubing
B. Install duct insulation
C. Connect longitudinal edges of rectangular duct
D. Connect flexible duct
Rationale: The Pittsburgh seam is one of the most common
longitudinal duct seams because it provides strength and an airtight
joint.
9. OSHA requires fall protection in construction when workers are
exposed to falls of:
A. 4 feet
B. 6 feet
