Which component is essential in a local exhaust system?

In a local exhaust system, the duct plays a crucial role. Its primary function is to capture and transport airborne contaminants directly from the source to the outside atmosphere or to a filtration system. This is fundamental in maintaining air quality and protecting the health of workers by reducing their exposure to harmful substances that might be generated during processes such as welding, grinding, or chemical handling.

The effectiveness of the local exhaust ventilation depends significantly on the design and integrity of the ductwork, which needs to be appropriately sized, installed, and sealed to minimize leaks and ensure efficient airflow. Without an effective duct system, the local exhaust system would fail to perform its intended function, thus compromising worker safety and regulatory compliance.

While the other components listed can play supportive roles in creating a comfortable environment (such as temperature control) or maintaining good air quality, they do not directly contribute to the exhaust of hazardous fumes or particles from a specific source. Therefore, they are not essential to the operation of a local exhaust system in the same way that ducts are.