🔍 Key Concepts

• Difference between cartridge-operated and stored-pressure dry chemical extinguishers • What can realistically be done aboard ship for maintenance/recharging • How operating pressure is supplied and controlled in each type

💭 Think About

• Think about which design lets you restore the extinguisher to service using simple tools and spare parts that could reasonably be carried on board. • Ask yourself: in normal portable extinguishers, which factor (time, range, weight, recharge method) is MOST affected by how the propellant (compressed gas) is stored? • Consider which option would be a practical reason a vessel might choose cartridge-operated units specifically for shipboard use.

✅ Before You Answer

• Verify how a cartridge-operated unit stores its propellant (separate gas cartridge vs. all pressure in main cylinder). • Check which features are typically almost the same between these two extinguishers (e.g., size, nozzle, agent quantity) so you don’t pick a difference that doesn’t really exist. • Confirm which design makes it easier to restore pressure after use without sending the extinguisher to a shore facility.