🔍 Key Concepts

• Types of marine fire streams (solid stream, low-velocity fog, high-velocity fog, foam) and what each nozzle looks like • How foam is generated when mixed with water – difference between chemical foam and mechanical foam • The role of an inductor or pick‑up tube attached to a fire hose in producing a specific extinguishing agent

💭 Think About

• Look closely at the extra hose/tube marked C and the fitting at A – what does that suggest is being drawn into the water stream? • Compare what you see at the discharge end D with a typical fog nozzle – does it look like a fog pattern generator or something designed to mix air and solution to create bubbles? • Ask yourself: which of the answer choices requires a separate can or tank of liquid concentrate plus an eductor/pick‑up tube like the one shown?

✅ Before You Answer

• Identify whether the device is primarily a nozzle that shapes water spray (for fog) or a mixing device for water and concentrate (for foam) • Recall that chemical foam is produced by a chemical reaction in the agent itself, while mechanical foam is produced by water + foam concentrate + air passed through a nozzle • Before choosing, verify which agent type is commonly produced on ships by a foam nozzle with a pick‑up tube dipped into a foam concentrate container