How is the discharge time period defined for flame extinguishment when using clean agents?

• A. Time to discharge 95 percent of agent mass at 70F to achieve the minimum design concentration with a 20 percent safety factor
• B. Time to discharge 100 percent of agent mass at 68F
• C. Time to discharge 50 percent of agent mass at 60F
• D. Time to discharge 95 percent of agent mass at 80F

Answer: (B)

Discharge time is defined as the time it takes to discharge the entire design mass of clean agent into the protected space, measured at a standard reference temperature of 68°F. This provides a consistent basis for evaluating performance because both the amount of agent released and the temperature conditions are standardized. Releasing only a portion of the mass or using other temperatures would not guarantee that the required extinguishing concentration is achieved, and it would make comparisons between systems unreliable. Therefore, the defined discharge time uses 100 percent of the design mass at 68°F.