What characteristic distinguishes a curtain type of CR fire damper?

What characteristic distinguishes a curtain type of CR fire damper?

• A. Square duct connection
• B. Frame and Blades recessed out of airstream
• C. Vertical mounting position
• D. Manual operation

Answer: (B)

The characteristic that distinguishes a curtain type of CR fire damper is that the frame and blades are recessed out of the airstream. This design allows the damper to effectively seal off the duct during a fire, limiting the spread of smoke and flames. When the fire damper is closed, the blades are positioned away from the airstream, which helps to prevent any obstruction in airflow under normal conditions and minimizes resistance when the system is operating. This recessed design is crucial because it enables the damper to remain unobtrusive during regular HVAC operation while still providing reliable protection in the event of a fire. The mechanism ensures that the damper can close effectively when activated by heat, without the blades interfering with the flow of air during non-emergency situations. Thus, the design serves both functional and safety purposes, aligning with the performance requirements outlined in standards such as the NFPA (National Fire Protection Association).

The characteristic that distinguishes a curtain type of CR fire damper is that the frame and blades are recessed out of the airstream. This design allows the damper to effectively seal off the duct during a fire, limiting the spread of smoke and flames. When the fire damper is closed, the blades are positioned away from the airstream, which helps to prevent any obstruction in airflow under normal conditions and minimizes resistance when the system is operating.

This recessed design is crucial because it enables the damper to remain unobtrusive during regular HVAC operation while still providing reliable protection in the event of a fire. The mechanism ensures that the damper can close effectively when activated by heat, without the blades interfering with the flow of air during non-emergency situations. Thus, the design serves both functional and safety purposes, aligning with the performance requirements outlined in standards such as the NFPA (National Fire Protection Association).