Duct systems shall not be interconnected with any other building _______ or _______ systems.

Duct systems shall not be interconnected with any other building _______ or _______ systems.

• A. Ventilation, Return
• B. Supply, Return
• C. Ventilation, Exhaust
• D. Combustion, Exhaust

Answer: (C)

Duct systems must be kept isolated from other air paths to prevent cross-contamination and pressure problems. If a ventilation duct were connected to an exhaust duct or to another building’s air system, contaminants, odors, or exhaust gases could flow into spaces that are supposed to receive fresh air, bypass filtration, or upset the intended pressure balance. Keeping ventilation and exhaust paths separate ensures that air delivery and contaminant removal stay controlled and safe, with appropriate filtration and ventilation performance. That’s why the requirement specifies ventilation and exhaust.

Duct systems must be kept isolated from other air paths to prevent cross-contamination and pressure problems. If a ventilation duct were connected to an exhaust duct or to another building’s air system, contaminants, odors, or exhaust gases could flow into spaces that are supposed to receive fresh air, bypass filtration, or upset the intended pressure balance. Keeping ventilation and exhaust paths separate ensures that air delivery and contaminant removal stay controlled and safe, with appropriate filtration and ventilation performance. That’s why the requirement specifies ventilation and exhaust.