What is the function of a ventilation hood and where is it used?

• A. Filters general room air to improve odor; used in offices.
• B. Helps heat buildings by circulating air; used in boiler rooms.
• C. Captures contaminants at source; used in laboratories and industrial processes to protect workers.
• D. Provides cooling to exterior equipment; used in outdoor areas.

Answer: (C)

Ventilation hoods function as local exhaust devices that capture contaminants right at the source, before they can disperse into the room. They create a controlled airflow that draws vapors, fumes, or dust away from the operator and into an exhaust system (often outside or through filtration). This setup protects workers by keeping hazardous substances contained where they’re produced. That’s why hoods are used in laboratories and various industrial processes where volatile chemicals or particulates are generated. They’re not meant to filter the entire room like a general air purifier, nor to heat spaces or provide cooling to outdoor equipment.