What type of system does a fire curtain represent?

A fire curtain is classified as a passive fire protection system that serves as a barrier to smoke and flames. Passive fire protection systems are designed to prevent the spread of fire and smoke within a building, allowing for safe evacuation routes and potentially limiting damage to the structure. Fire curtains are typically made from non-combustible materials and are deployed to contain a fire within designated areas, preventing it from engulfing the entire structure. By effectively compartmentalizing spaces, fire curtains help to maintain safe environments during a fire incident, providing critical time for evacuation and reducing the risk of injury or loss of life.

In contrast, active fire protection systems, such as sprinklers or fire alarms, require action to function, while detection systems for fire hazards focus on identifying the presence of fire or smoke rather than containing it. Additionally, options that involve cooling the air during a fire are not relevant to the function of fire curtains, which specifically serve to block and contain smoke and flames rather than manipulating temperature.