🔍 Key Concepts

• Function of the handle-operated diaphragm valve as shown in the cutaway • How a flushometer valve controls a high-pressure water flush using inlet pressure and a diaphragm chamber • Differences between pressure-control devices like relief valves/back pressure regulators and manually operated discharge valves

💭 Think About

• Look closely at the flow path: where is the INLET, where is the OUTLET, and what happens when the handle is moved? Does this look like something that protects a system from overpressure, or something that releases a measured slug of water? • Focus on the large diaphragm chamber (I) and the small passage (H). What is the purpose of slowly venting and refilling that chamber in real-world plumbing devices? • Compare each answer choice to the parts shown: which of these devices normally has a handle (E) for manual operation and is mounted directly on a supply line to discharge straight down?

✅ Before You Answer

• Verify which of the listed devices commonly includes a manual handle and diaphragm assembly arranged vertically with flow straight down. • Confirm which option is specifically designed for rapid, timed discharge of water rather than continuous pressure regulation or overflow protection. • Eliminate any device types that do not typically use a manual operating handle or that are purely automatic pressure-control valves.