ASCS ASCS Equipment and Tools

Question 1

What is the primary function of a negative air machine used during duct cleaning?

Accepted Answer

To create negative pressure inside the duct system so contaminants are captured rather than released

Answer

A negative air machine draws air through the duct system under controlled negative pressure, ensuring dislodged contaminants flow into a HEPA filtration unit rather than into occupied spaces.

Question 2

What type of filter should a negative air machine use to capture fine particulates during duct cleaning?

Accepted Answer

HEPA filter rated to capture 99.97% of particles at 0.3 microns

Answer

HEPA filters capture 99.97% of particles at 0.3 microns, ensuring that fine dust, mold spores, and other contaminants do not escape back into the building.

Question 3

Which type of brush is most commonly used for mechanical agitation of debris inside rectangular sheet metal ducts?

Accepted Answer

Rotary or spinning brush attached to a flexible rod or drill

Answer

Rotary brushes attached to flexible extension rods allow technicians to agitate debris along the full length of rectangular ductwork from a single access point.

Question 4

What is the purpose of an air whip or skipper ball tool in duct cleaning?

Accepted Answer

To use compressed air to propel the tool through ducts and dislodge debris with air jets

Answer

Air whips and skipper balls use compressed air jets to propel themselves through ductwork while simultaneously blasting debris loose toward the collection point.

Question 5

What is the minimum CFM (cubic feet per minute) capacity typically recommended for a negative air machine used in commercial duct cleaning?

Accepted Answer

At least 1,000 CFM to maintain adequate negative pressure in larger systems

Answer

A minimum of 1,000 CFM is typically required for commercial systems to maintain sufficient negative pressure and capture dislodged debris effectively.

(ASCS) Air Systems Cleaning Specialist Certification Practice Test

(ASCS) Air Systems Cleaning Specialist Certification Practice Test

ASCS ASCS Equipment and Tools