Which feature best describes an Airborne Infection Isolation Room (AIIR) used for airborne pathogens?

• A. Negative pressure relative to surrounding areas
• B. Positive pressure relative to surrounding areas
• C. Neutral pressure with no air exchange
• D. Sealed glass room with no ventilation

Answer: (A)

Airborne pathogens spread is best controlled by creating a space where air flows into the room rather than out to the surrounding areas. An Airborne Infection Isolation Room is kept at negative pressure compared to adjacent spaces, so airflow moves toward the room from the hall and contaminated air is removed through a dedicated exhaust system, often treated with filtration or directed outside. This setup helps prevent pathogens from entering other rooms or areas of the facility.

Maintaining negative pressure, along with keeping doors closed and ensuring appropriate air changes, minimizes the chance that infectious aerosols escape the room. If the room were at neutral or positive pressure, contaminated air could leak into surrounding spaces, risking transmission. A sealed room with no ventilation would also fail to remove contaminants and could allow buildup of infectious particles.

So, the negative-pressure design is the key feature that makes the AIIR effective for airborne pathogens.