Which statement about negative air machines is true?

Which statement about negative air machines is true?

• A. They increase the flow of contaminated air into clean areas.
• B. They help create and maintain negative pressure by moving air and filtering it.
• C. They are used only for ventilation of outdoor spaces.
• D. They replace PPE for workers.

Answer: (B)

Negative air machines create and maintain a negative-pressure environment by moving room air through filtration and exhausting it away from clean areas. They draw air from the space, filter it (typically with HEPA filters), and exhaust it outside or into a dedicated exhaust path. By moving more air out than is supplied, they reduce the room’s pressure relative to surrounding spaces, which helps keep contaminated aerosols from flowing into adjacent, cleaner areas. This containment is essential during renovations, in containment zones, or whenever airborne contaminants need to be controlled. They don’t work by increasing contaminated air into clean spaces, aren’t used solely for outdoor ventilation, and do not replace PPE—the protective gear for workers is still required.

Negative air machines create and maintain a negative-pressure environment by moving room air through filtration and exhausting it away from clean areas. They draw air from the space, filter it (typically with HEPA filters), and exhaust it outside or into a dedicated exhaust path. By moving more air out than is supplied, they reduce the room’s pressure relative to surrounding spaces, which helps keep contaminated aerosols from flowing into adjacent, cleaner areas. This containment is essential during renovations, in containment zones, or whenever airborne contaminants need to be controlled. They don’t work by increasing contaminated air into clean spaces, aren’t used solely for outdoor ventilation, and do not replace PPE—the protective gear for workers is still required.