🔍 Key Concepts

• Boiler fuel oil system layout – know where fuel is controlled closest to the burner • Difference between slow manual valve actions and emergency quick‑acting devices • Purpose of an emergency fuel shutdown in a fire situation

💭 Think About

• Which option directly and immediately stops fuel going to the burner, without relying on multiple valves or distant tanks? • In a fire or fuel leak, which device is specifically designed for rapid, emergency operation by one action? • Do any of the options describe something that merely redirects or recirculates oil instead of actually shutting the fuel off?

✅ Before You Answer

• Identify which choice is an emergency device rather than a normal operating valve. • Check which valves (settling tank or double bottom) are farther from the burner and slower to operate in an emergency. • Confirm whether any option does not stop fuel flow, but only changes where the oil goes.