Which gas is commonly used as a propellant in installed fire extinguishing systems?

In installed fire extinguishing systems, nitrogen is commonly used as a propellant due to its inert properties and effectiveness in various applications. When utilized in systems such as automatic fire extinguishers, nitrogen provides the necessary pressure to discharge fire-suppressing agents quickly and efficiently.

This inert gas does not contribute to combustion, making it a safe option for use in environments where fire suppression is required. By pressurizing a fire suppression agent, nitrogen ensures that the extinguishing substance reaches the fire effectively, covering the area and suppressing flames to help minimize damage and control the situation.

While other gases like carbon dioxide can also be used for fire extinguishing, in the context of installed systems where a propellant must facilitate the release of fire suppression agents, nitrogen is preferred for its non-flammable characteristics and reliability in displacing oxygen and smothering combustion.