Which gas is most commonly used for inerting in fire safety?

Nitrogen is the gas most commonly used for inerting in fire safety due to its properties and availability. Inerting is a process that involves displacing oxygen in a given environment with an inert gas to prevent the ignition of flammable materials or to suppress combustion. Nitrogen is particularly effective because it is non-flammable, non-toxic, and makes up a significant portion of the Earth's atmosphere, which makes it readily available and economical.

By reducing the concentration of oxygen below the levels required for combustion, nitrogen helps create an atmosphere where fires cannot easily start or spread. Its inert nature means it does not react with other substances, which is crucial in preventing the risk of a fire. Other gases like carbon dioxide and argon can also be used for inerting purposes; however, nitrogen is preferred in many applications due to its cost-effectiveness and sufficient ability to displace oxygen.

Oxygen, on the other hand, is essential for combustion and would not be used in inerting applications, while carbon dioxide, while sometimes used for fire suppression, can be hazardous in certain concentrations. Argon, though inert, is less commonly utilized than nitrogen for practical and economic reasons in fire safety contexts.