What type of device is used to capture grease and contaminants before they enter a duct system?

The correct answer is that a hood is specifically designed to capture grease and contaminants before they enter a duct system. In commercial kitchens and similar environments, hood systems, often referred to as exhaust hoods or kitchen hoods, are installed above cooking equipment to effectively trap airborne particles, grease, steam, and heat generated during cooking processes.

The functional design of the hood includes a series of filters that help in removing these contaminants from the air before it is expelled through the ductwork. Proper installation and maintenance of the hoods are critical for ensuring they perform effectively, maintaining air quality, and preventing fire hazards caused by built-up grease.

Other devices, such as filters and separators, play roles in air quality control and pollution management, but they do not directly capture contaminants at the source as effectively as hoods in a cooking environment. Ventilators are typically used for air circulation and might not specifically target grease or cooking-related contaminants. Thus, hoods are essential for ensuring that greasy air is captured right at the source, preventing it from entering the duct system and causing potential buildup or hazards.