Ballast water
Sea water taken into ballast tanks to stabilise a vessel — subject to strict management under the BWM Convention to prevent invasive species transfer.
Regulatory detail & full definition
Ballast water is sea water taken into dedicated ballast tanks to provide stability + trim when a ship is empty, partially loaded, or transiting. On tankers + bulkers, ballast operations are constant — loaded/laden ballast, sea passage ballast, part-cargo ballast. See /glossary/ballast-water-management for the regulatory regime + /glossary/ballast-water-record-book for the documentation duty.
Authoritative source: IMO — BWM ↗
Related
Source: BWM Convention
High confidence
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