🔍 Key Concepts
• Fire class definitions (Class A, B, C, D and what each one involves)
• Special extinguishing agents used on metal fires
• Why common water or foam agents can be dangerous on certain types of fires
💭 Think About
• Think about what kind of materials sodium chloride (salt) and graphite are meant to cover or smother. Are they more suitable for wood/paper, flammable liquids, energized electrical equipment, or burning metals?
• Ask yourself: which fire class involves materials that may react violently with water or standard extinguishers, requiring special dry agents?
• Consider where you are most likely to find this type of extinguisher on a ship: in an office space, near fuel, near electrical panels, or near areas with special metal components?
✅ Before You Answer
• Review the definition of each fire class (A, B, C, D) and match them to typical cargo or materials on board.
• Verify which fire class specifically involves combustible metals such as magnesium, sodium, potassium, aluminum powder, etc.
• Confirm which extinguishing agent mixture of graphite and sodium chloride is designed for, and why it would NOT be used on ordinary combustibles, liquids, or just electrical fires.