Emergency Shutdown
Abbreviation: ESD
Automated/manual system that stops cargo transfer in seconds when a high-level alarm, leak, or other unsafe condition is detected.
In practice
Tested before every cargo operation as part of the ship/shore checklist. The cargo control room operator verifies ESD-1 and ESD-2 functions; the terminal does the same shore-side. Activation during cargo flow stops pumps within 30 seconds; pressure surge in the cargo line is the primary risk.
Regulatory detail & full definition
On gas carriers ESD-1 closes ship valves; ESD-2 also closes shore valves via the Ship/Shore Link. Activated by tank high-high level, manifold leak detection, manual buttons at strategic points (CCR, manifold, accommodation). Shut-down sequence is typically completed within 30 seconds to avoid pressure surge in cargo lines.
Authoritative source: IACS Unified Requirements ↗
Related
Source: OCIMF Ship/Shore Interface Guidelines; IACS UR Z14 (gas carrier ESD)
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