What type of water-based fire protection system uses a proportioning valve?

What type of water-based fire protection system uses a proportioning valve?

• A. Deluge System
• B. Wet Pipe System
• C. Foam System
• D. Dry Pipe System

Answer: (C)

Foam systems incorporate a foam concentrate into the water stream to create a foam solution that blankets the fire. A proportioning valve (or similar proportioning device) is used to mix the foam concentrate with the water at the correct ratio before it leaves the system. That blending capability is what defines a foam system. The other options simply deliver water through the pipes: deluge systems have all discharge openings open, wet pipes are filled with water, and dry pipes are charged with pressurized air until release. None of these introduce a foam concentrate, so they don’t use a proportioning valve.

Foam systems incorporate a foam concentrate into the water stream to create a foam solution that blankets the fire. A proportioning valve (or similar proportioning device) is used to mix the foam concentrate with the water at the correct ratio before it leaves the system. That blending capability is what defines a foam system.

The other options simply deliver water through the pipes: deluge systems have all discharge openings open, wet pipes are filled with water, and dry pipes are charged with pressurized air until release. None of these introduce a foam concentrate, so they don’t use a proportioning valve.