Each AFFF mixing station has which valves?

• A. SOPV only
• B. PVR and Cross Valve
• C. SOPV and Powertrol Valve
• D. Ball Valve and Gate Valve

Answer: (C)

The mixing station relies on two key valves: a Solenoid Operated Proportioning Valve (SOPV) and a Powertrol valve. The SOPV precisely meters the foam concentrate into the water stream to achieve the correct foam solution ratio, regardless of changes in water flow. The Powertrol valve provides the main flow control and can be operated automatically or remotely as part of the system’s control logic, with manual override if needed. Together, they enable reliable, automatic mixing and safe operation of the AFFF system. Other options don’t provide this essential combination: a single SOPV lacks the main flow control, and the other pairings involve valves (like generic ball or gate valves, or components not standard to mixing stations) that don’t deliver the required proportioning and control.