There are 3 parts to a foam system: 1) The foam concentrate ( class A or B) 2) Nozzle (125 GPM) 3) Eductor

• A. The foam concentrate (Class A or B)
• B. The foam concentrate (Class A or B); Nozzle (125 GPM); Eductor
• C. The foam concentrate; Nozzle; Valve
• D. The foam concentrate; Hose; Eductor

Answer: (B)

In a foam system, three elements must work together: the foam concentrate, the nozzle, and the eductor. The concentrate provides the chemical foam solution and can be Class A or Class B depending on the fire scenario. The nozzle sets the water flow and delivery rate, and in many foam setups a 125 GPM nozzle is used to ensure the correct amount of water passes through the system to carry and mix the concentrate properly. The eductor is the device that uses Venturi action to draw the concentrate into the water stream and blend it into the foam solution.

Having all three components is essential because you need a source of concentrate, a means to deliver water at the proper rate, and a mechanism to mix the concentrate into that water. Omitting any of these parts means the foam system can’t function as intended.