What does a manual release cause when activated?

• A. It triggers the alarm only.
• B. It closes all valves.
• C. It disables the system.
• D. It causes simultaneous operation of automatically operated valves controlling agent release and distribution.

Answer: (D)

When you activate a manual release on a clean agent system, you are initiating the release sequence rather than just sounding an alarm. The manual release provides a direct control input to the system that energizes the actuators for the release valves and the distribution valves. In other words, it makes the automatically operated valves that control agent release and the distribution network open at the same time, delivering the agent to the protected spaces in a coordinated way. This is why the correct concept is that the manual release causes simultaneous operation of valves that control both agent release and distribution.