Air Systems Cleaning Specialist (ASCS) Practice Exam

The most common control release mechanism for fire dampers is fusible links. Fusible links are small mechanical devices designed to respond to heat; when a specific temperature is reached, usually due to a fire, the material within the link melts. This causes the damper to close automatically, preventing the spread of fire and smoke through ductwork and improving the safety of the building.

Fusible links are widely used due to their simplicity, reliability, and effectiveness in fire protection systems. They require no external power source, making them a practical choice for a variety of building types. The passive nature of fusible links aligns with the goal of maintaining safety and minimizing maintenance needs over time.

Other mechanisms like pneumatic controls and electromagnetic controls may also be used in modern HVAC systems but are not as common as fusible links for this specific application. They often involve more complexity, including the need for a compressed air source or electrical power, which can complicate system reliability during a fire event. Pulling the building fire alarm device does activate fire safety systems but is not a direct method for the control of fire dampers themselves.