During an extended discharge, how should additional agent be applied?

• A. At a reduced rate
• B. At the same rate as the initial discharge
• C. At a variable rate depending on occupancy
• D. Only after AHJ approval

Answer: (C)

During an extended discharge, you adjust the additional agent delivery rather than keep it at the initial surge rate. The aim is to maintain the required design concentration in the space as conditions change—such as people occupying or vacating the area and the fire evolving—so you deliver more agent when needed to keep protection, and less when occupancy or fire conditions demand it. This makes the discharge rate variable and responsive to occupancy and fire progress.

Why this approach fits better than a fixed rate: a fixed reduced rate might under-protect if the space still requires suppression, and a fixed rate that mirrors the initial discharge could overexpose occupants or waste agent. Relying on AHJ approval to proceed would delay protection and isn’t how extended- discharge control is typically managed.