Florida Sheet Metal Contractor Licensing
Exam 2025/2026
Coverage: Florida Building Code (Mechanical), SMACNA standards, fabrication tolerances,
HVAC airflow, fire/smoke dampers, welding & fastening, insulation, corrosion protection,
safety, contracts, and project management.
1. Under the Florida Mechanical Code, supply air ducts in plenums must be
constructed of:
A. Any combustible material
B. Noncombustible materials or approved fire-resistant construction
C. PVC only
D. Flexible duct only
✅ Correct Answer: B
Rationale: Plenum spaces require noncombustible or fire-rated materials to limit fire spread.
2. Which fastening method is acceptable for longitudinal duct seams exceeding 20
inches in width?
A. Adhesive only
B. Standing seam with mechanical reinforcement
C. Tape only
D. Spot welding without reinforcement
✅ Correct Answer: B
Rationale: Large ducts require mechanically reinforced seams per SMACNA pressure class
tables.
3. Which gauge is typically required for rectangular ducts operating at higher
static pressures?
A. Thinner gauge
B. Thicker gauge
C. Any gauge
D. Plastic
,✅ Correct Answer: B
Rationale: Higher pressures require thicker metal to resist deformation and leakage.
4. Fire dampers must be installed:
A. Only in exterior walls
B. At rated wall and floor penetrations
C. Only above ceilings
D. Only in return ducts
✅ Correct Answer: B
Rationale: Dampers maintain fire-resistance of rated assemblies.
5. Which method best prevents galvanic corrosion between dissimilar metals?
A. Painting only
B. Electrical isolation using dielectric barriers
C. Increasing airflow
D. Thicker metal
✅ Correct Answer: B
Rationale: Isolating metals prevents electrochemical reaction.
6. When welding galvanized steel, the primary safety hazard is:
A. Noise
B. Zinc oxide fumes causing metal fume fever
C. Eye strain
D. Heat loss
✅ Correct Answer: B
Rationale: Vaporized zinc creates toxic fumes requiring ventilation and PPE.
7. Turning vanes in duct elbows primarily improve:
A. Noise only
B. Airflow efficiency and reduced pressure loss
,C. Structural strength
D. Insulation value
✅ Correct Answer: B
Rationale: Vanes guide airflow and minimize turbulence.
8. What is the main purpose of duct leakage testing?
A. Measure temperature
B. Verify system energy efficiency and code compliance
C. Test insulation thickness
D. Test noise
✅ Correct Answer: B
Rationale: Excess leakage wastes energy and violates code limits.
9. Flexible ducts in concealed spaces must be supported at intervals not
exceeding:
A. 2 feet
B. 4 feet
C. 6 feet
D. 10 feet
✅ Correct Answer: B
Rationale: Florida Mechanical Code requires support at 4-foot intervals to prevent sagging.
10. Which insulation vapor retarder placement prevents condensation in cooling
systems?
A. Inside liner
B. Exterior vapor barrier on insulation
C. No vapor barrier
D. Between metal layers
✅ Correct Answer: B
Rationale: Vapor barrier must be on warm side to block moisture infiltration.
, 11. Smoke dampers are required when ducts penetrate:
A. Any partition
B. Smoke barriers and smoke partitions
C. Only exterior walls
D. Mechanical rooms only
✅ Correct Answer: B
Rationale: Smoke dampers prevent smoke migration across smoke-rated assemblies.
12. Which joint sealing class provides the lowest allowable duct leakage?
A. Class A
B. Class B
C. Class C
D. No sealing
✅ Correct Answer: A
Rationale: Class A requires sealing of all seams and joints.
13. Which duct material is prohibited in environmental air plenums?
A. Aluminum
B. Galvanized steel
C. Fiberglass duct board without fire rating
D. Stainless steel
✅ Correct Answer: C
Rationale: Materials must meet flame spread and smoke-developed limits.
14. Which practice best controls vibration transmission to ductwork?
A. Rigid connections only
B. Flexible connectors and isolation hangers
C. Heavier gauge metal
D. Higher airflow
✅ Correct Answer: B
Rationale: Isolation prevents mechanical vibration transfer.
Exam 2025/2026
Coverage: Florida Building Code (Mechanical), SMACNA standards, fabrication tolerances,
HVAC airflow, fire/smoke dampers, welding & fastening, insulation, corrosion protection,
safety, contracts, and project management.
1. Under the Florida Mechanical Code, supply air ducts in plenums must be
constructed of:
A. Any combustible material
B. Noncombustible materials or approved fire-resistant construction
C. PVC only
D. Flexible duct only
✅ Correct Answer: B
Rationale: Plenum spaces require noncombustible or fire-rated materials to limit fire spread.
2. Which fastening method is acceptable for longitudinal duct seams exceeding 20
inches in width?
A. Adhesive only
B. Standing seam with mechanical reinforcement
C. Tape only
D. Spot welding without reinforcement
✅ Correct Answer: B
Rationale: Large ducts require mechanically reinforced seams per SMACNA pressure class
tables.
3. Which gauge is typically required for rectangular ducts operating at higher
static pressures?
A. Thinner gauge
B. Thicker gauge
C. Any gauge
D. Plastic
,✅ Correct Answer: B
Rationale: Higher pressures require thicker metal to resist deformation and leakage.
4. Fire dampers must be installed:
A. Only in exterior walls
B. At rated wall and floor penetrations
C. Only above ceilings
D. Only in return ducts
✅ Correct Answer: B
Rationale: Dampers maintain fire-resistance of rated assemblies.
5. Which method best prevents galvanic corrosion between dissimilar metals?
A. Painting only
B. Electrical isolation using dielectric barriers
C. Increasing airflow
D. Thicker metal
✅ Correct Answer: B
Rationale: Isolating metals prevents electrochemical reaction.
6. When welding galvanized steel, the primary safety hazard is:
A. Noise
B. Zinc oxide fumes causing metal fume fever
C. Eye strain
D. Heat loss
✅ Correct Answer: B
Rationale: Vaporized zinc creates toxic fumes requiring ventilation and PPE.
7. Turning vanes in duct elbows primarily improve:
A. Noise only
B. Airflow efficiency and reduced pressure loss
,C. Structural strength
D. Insulation value
✅ Correct Answer: B
Rationale: Vanes guide airflow and minimize turbulence.
8. What is the main purpose of duct leakage testing?
A. Measure temperature
B. Verify system energy efficiency and code compliance
C. Test insulation thickness
D. Test noise
✅ Correct Answer: B
Rationale: Excess leakage wastes energy and violates code limits.
9. Flexible ducts in concealed spaces must be supported at intervals not
exceeding:
A. 2 feet
B. 4 feet
C. 6 feet
D. 10 feet
✅ Correct Answer: B
Rationale: Florida Mechanical Code requires support at 4-foot intervals to prevent sagging.
10. Which insulation vapor retarder placement prevents condensation in cooling
systems?
A. Inside liner
B. Exterior vapor barrier on insulation
C. No vapor barrier
D. Between metal layers
✅ Correct Answer: B
Rationale: Vapor barrier must be on warm side to block moisture infiltration.
, 11. Smoke dampers are required when ducts penetrate:
A. Any partition
B. Smoke barriers and smoke partitions
C. Only exterior walls
D. Mechanical rooms only
✅ Correct Answer: B
Rationale: Smoke dampers prevent smoke migration across smoke-rated assemblies.
12. Which joint sealing class provides the lowest allowable duct leakage?
A. Class A
B. Class B
C. Class C
D. No sealing
✅ Correct Answer: A
Rationale: Class A requires sealing of all seams and joints.
13. Which duct material is prohibited in environmental air plenums?
A. Aluminum
B. Galvanized steel
C. Fiberglass duct board without fire rating
D. Stainless steel
✅ Correct Answer: C
Rationale: Materials must meet flame spread and smoke-developed limits.
14. Which practice best controls vibration transmission to ductwork?
A. Rigid connections only
B. Flexible connectors and isolation hangers
C. Heavier gauge metal
D. Higher airflow
✅ Correct Answer: B
Rationale: Isolation prevents mechanical vibration transfer.
