What percentage inert agent loss requires refilling?

• A. 5%
• B. 1%
• C. 3%
• D. 7%

Answer: (A)

The main idea here is how much inert agent can be lost before you must recharge the system. Inert gas fire suppression systems are designed to maintain a specific agent concentration for effective protection, but small amounts can leak over time. A standard threshold used in practice is 5% of the nominal stored quantity. When the measured loss reaches 5% or more, the system should be refilled to its required total amount to ensure it can still deliver the intended concentration. This 5% limit balances the realities of minor leaks with the need to guarantee reliable performance. If the loss is less than 5%, maintenance monitors the system and plans for future recharge; if it’s 5% or more, recharge and then verify the system’s concentration after replenishment.