Fire dampers shall meet the requirements set forth in which UL standard?

• A. 263
• B. 555
• C. 555C
• D. 555S

Answer: (B)

Fire dampers must meet the requirements set forth in UL Standard 555, which specifically addresses the testing and performance criteria for fire dampers in HVAC systems. This standard outlines how fire dampers are to be constructed and tested to ensure they can effectively prevent the spread of fire through ductwork, thus maintaining the integrity of fire-rated walls and ceilings. The UL 555 standard is crucial for ensuring that these devices will close securely in the event of a fire, thereby playing a vital role in fire protection systems.

The other UL standards mentioned focus on different aspects of fire protection or testing procedures. For instance, UL 263 pertains to the fire-resistance ratings of various building components, while UL 555C covers smoke dampers specifically and their ability to control smoke movement. UL 555S, on the other hand, relates to the operational testing of smoke dampers. These distinctions emphasize that UL 555 is the proper standard specifically for fire dampers, ensuring they meet safety and performance requirements when fire emergencies occur.