Which option describes the correct location for introducing foam concentrate into the system?

• A. Injected into the nozzle
• B. Added at the pump
• C. Inducted into the line
• D. Dripped into the water

Answer: (C)

Foam concentrates must be mixed with water in a controlled proportion as the water flows, so the foam solution is stable and effective when it reaches the fire area. Introducing the concentrate into the line uses a foam proportioner or eductor that draws the concentrate into the moving water, creating a consistent, properly mixed foam solution before the water reaches the nozzle. This method ensures the right foam-to-water ratio and reliable performance across the system.

Injecting into the nozzle can disrupt the spray pattern and risk nozzle blockage or poor foam quality. Adding at the pump may work in some setups but doesn’t guarantee correct distribution through the entire line. Dripping into the water would yield an inconsistent, unreliable mixture and poor foam performance.