🔍 Key Concepts

• Carefully compare each numbered symbol in D039SA that shows piping or valves, not hoses or portable gear. • Remember that a fire main is the fixed water piping system running through the ship, with hydrants/valves connected to it. • Note that many symbols use letters like P, F, W, S to indicate portable, foam, water, or sprinkler — ask whether those letters fit a fire main with valves.

💭 Think About

• Which of the four numbers (17, 34, 51, 56) is drawn as a section of pipe with valves rather than as a nozzle, hydrant, or remote control? • Look at where similar shapes appear elsewhere on the sheet: do any of the four options match other obvious valve or pipeline symbols? • Does any option clearly represent a system component (part of a pipeline) instead of an individual piece of equipment like a monitor, nozzle, or extinguisher?

✅ Before You Answer

• Verify that the symbol you pick is part of a pipeline, not a stand‑alone device such as a hose, reel, or nozzle. • Check that the symbol suggests multiple valves or a controllable section of main, not just a single shutoff valve. • Make sure the symbol does not include letters like P (portable) or W (water nozzle), which would point to other types of equipment.