🔍 Key Concepts

• Fixed Halon (or clean agent) fire extinguishing systems on vessels • Difference between an operating/control device vs a pressure‑relief or safety device • How cylinders are protected from burst if pressure rises due to heat

💭 Think About

• Which device is designed to open permanently or fail once when pressure is too high, rather than open and reseat repeatedly? • Which of these options is normally part of the actuation mechanism, and which are dedicated to protecting the cylinder from over‑pressure? • Think about what component is designed as a thin membrane or section that breaks at a set pressure.

✅ Before You Answer

• Identify which choices are specifically over‑pressure protection devices, not general operating parts • Recall that a control head is associated with how the system is actuated, not how it is protected from excess pressure • Distinguish between devices that reset themselves after venting and those that are one‑time use, non‑resetting pressure reliefs