What device introduces foam concentrate into the water stream to form the foam solution?

• A. Foam nozzle
• B. Foam proportioner
• C. Venturi injector
• D. Mixer

Answer: (B)

Foam solution is formed when foam concentrate is added to water at the correct ratio. The device that does this addition in the water stream is the foam proportioner; it meters the proper amount of concentrate into the water so the mixture becomes the foam solution used for firefighting. A Venturi injector accomplishes the same task by using the Venturi effect to pull concentrate into the water, but it’s a specific type of proportioner. The foam nozzle shapes and discharges the foam, while a mixer isn’t typically used to inject concentrate into the live water line.