Hood: Collects contaminants at the source

Hood: Collects contaminants at the source

• A. LEV Components
• B. Local Exhaust Ventilation (LEV)
• C. Measuring Velocity
• D. Total Pressure (TP)

Answer: (A)

Capturing contaminants at the source is the primary role of a hood within a ventilation system. A hood is a capture device designed to intercept pollutants as soon as they are generated, pulling them into the system before they spread. In practice, this capture function is one part of a local exhaust ventilation (LEV) system, which also includes ductwork, a fan, and filtration or discharge components. The hood’s effectiveness depends on its design and the face velocity at the opening, which determine how well it pulls contaminants into the system. The term LEV describes the whole system, not just the hood, while measuring velocity or total pressure relate to performance checks or pressures in the ductwork, not the hood’s purpose of capturing at the source.

Capturing contaminants at the source is the primary role of a hood within a ventilation system. A hood is a capture device designed to intercept pollutants as soon as they are generated, pulling them into the system before they spread. In practice, this capture function is one part of a local exhaust ventilation (LEV) system, which also includes ductwork, a fan, and filtration or discharge components. The hood’s effectiveness depends on its design and the face velocity at the opening, which determine how well it pulls contaminants into the system. The term LEV describes the whole system, not just the hood, while measuring velocity or total pressure relate to performance checks or pressures in the ductwork, not the hood’s purpose of capturing at the source.