Fixed CO2 fire-extinguishing system
SOLAS-required fixed gaseous fire-extinguishing system used to flood machinery + cargo spaces with CO2 to suppress fire by oxygen displacement.
Regulatory detail & full definition
SOLAS Chapter II-2 requires a fixed gaseous fire-extinguishing system for enclosed machinery spaces + cargo spaces + emergency generator room. The most common gas is CO2; alternatives include high-pressure water mist + inert gas (nitrogen / IG-541). Activation is a two-step deliberate release (release-cabinet key + pin) with automatic evacuation alarm + interlocks that shut engine-room ventilation before discharge. Fatal-to-humans in the flooded space; SMS and drills must exclude release with personnel inside.
Authoritative source: IMO — Fire Safety ↗
Related
Source: SOLAS II-2 + FSS Code
High confidence
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