SMACNA Air Duct Leakage Testing

SMACNA Air Duct Leakage Testing Certification Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of air duct leakage testing?

a) To verify duct insulation levels

b) To measure air loss through ductwork under test pressure

c) To determine airflow velocity

d) To balance the HVAC system

Rationale: The purpose of leakage testing is to quantify how much

air escapes through joints and fittings under controlled test pressure conditions.

• Which organization publishes the standard for duct leakage testing?

a) ASHRAE 1 / 4

b) AABC

c) SMACNA

d) AMCA

Rationale: The Sheet Metal and Air Conditioning Contractors'

National Association (SMACNA) issues the official duct leakage testing standards.

• What is the typical unit used to express duct leakage?

a) CFM per square foot

b) CFM per 100 square feet of duct surface area

c) Inches of water column

d) Cubic feet per minute per joint

Rationale: Leakage is standardized as cubic feet per minute (CFM)

per 100 square feet of duct surface area.

• What is the standard test pressure for low-pressure ducts?
• 10 in. w.g.
• 8 in. w.g.
• 1.0 in. w.g.
• 3.0 in. w.g.

Rationale: SMACNA defines 1 in. w.g. as the standard test pressure

for low-pressure duct systems. 2 / 4

• What is the standard test pressure for high-pressure rectangular

ducts?

• 1 in. w.g.
• 2 in. w.g.
• 10 in. w.g.
• 15 in. w.g.

Rationale: High-pressure ducts are tested at 10 inches of water

gauge to simulate operational pressure conditions.

• Which instrument measures air leakage rate?

a) Manometer

b) Pressure transducer

c) Flow hood or flowmeter

d) Anemometer

Rationale: A calibrated flowmeter or flow hood measures the

amount of air escaping the duct system during the test.

• What does "CFM" stand for?

a) Cubic Feet per Meter

b) Cubic Flow Measurement

c) Cubic Feet per Minute 3 / 4

d) Constant Flow Measurement

Rationale: CFM stands for cubic feet per minute, indicating airflow

rate.

• What type of duct system is typically tested for leakage?

a) Only exhaust ducts

b) Only low-pressure systems

c) Supply, return, and exhaust ducts depending on specification

d) Only new systems

Rationale: Testing may include any duct type specified in the design

documents or project standards.

• When should duct leakage testing be performed?

a) After all finishes are complete

b) Before ducts are insulated

c) Before the ceiling is closed or insulated

d) During system commissioning only

Rationale: Testing should occur before ducts are concealed to allow

access for sealing leaks.

• What is the maximum allowable leakage class for high-pressure

ducts per SMACNA?

• / 4