ASCS ASCS Equipment and Tools 2 — Questions and Answers
Question 1: What is the purpose of a video inspection camera system in air duct cleaning?
- To inspect duct interiors for debris, damage, and cleanliness before and after cleaning (Correct answer)
- To record employee work hours
- To check electrical wiring inside walls
- To measure ambient CO2 levels
Correct answer: To inspect duct interiors for debris, damage, and cleanliness before and after cleaning
Video inspection cameras allow technicians to visually document interior duct conditions, confirm cleaning effectiveness, and identify physical defects that require repair.
Question 2: Which instrument is used to measure airflow velocity inside ductwork during an HVAC assessment?
- Anemometer or pitot tube manometer (Correct answer)
- Hygrometer
- Thermographic camera
- Particle counter
Correct answer: Anemometer or pitot tube manometer
An anemometer measures air velocity directly, while a pitot tube with manometer measures velocity pressure to calculate airflow, both being standard tools for HVAC assessment.
Question 3: What is the role of a HEPA vacuum during duct cleaning?
- To capture fine particulates that are disturbed or dislodged during the cleaning process (Correct answer)
- To pressurize ducts for leak detection
- To sanitize surfaces with heat
- To measure filter efficiency
Correct answer: To capture fine particulates that are disturbed or dislodged during the cleaning process
A HEPA vacuum collects fine particles that are loosened during mechanical agitation or compressed air cleaning, preventing them from becoming airborne in the occupied space.
Question 4: What type of access tool is used to create openings in sheet metal ductwork when manufacturer-installed access doors are not present?
- Sheet metal cutters or aviation snips to create access panels that are later resealed (Correct answer)
- Standard drill bits only
- Angle grinder with cutting disc only
- Reciprocating saw without any cover
Correct answer: Sheet metal cutters or aviation snips to create access panels that are later resealed
Aviation snips or sheet metal cutters create clean-edged access openings that can be properly covered with sheet metal patches or access panels after cleaning is complete.
Question 5: Why is it important to select the correctly sized negative air machine for a specific duct cleaning job?
- An undersized unit cannot maintain negative pressure while an oversized unit may damage flexible ductwork (Correct answer)
- Size only affects noise level, not performance
- All negative air machines perform identically regardless of CFM
- Larger units always provide better results without risk
Correct answer: An undersized unit cannot maintain negative pressure while an oversized unit may damage flexible ductwork
Matching machine capacity to system size ensures adequate negative pressure is maintained without creating pressure differentials that could collapse flexible ductwork sections.
Question 6: Which personal protective equipment (PPE) should ASCS technicians wear when cleaning systems with visible mold contamination?
- N95 or higher respirator, gloves, and protective coveralls at minimum (Correct answer)
- Safety glasses only
- Steel-toed boots only
- Standard dust mask and work gloves
Correct answer: N95 or higher respirator, gloves, and protective coveralls at minimum
Visible mold requires respiratory protection at N95 or higher, plus gloves and coveralls to prevent skin contact and inhalation of mold spores during disturbance.
ASCS ASCS Equipment and Tools 2
What is the purpose of a video inspection camera system in air duct cleaning?