Snap-Back Zone
Area on deck within which a parted mooring line can whip back; standing in this zone has killed many seafarers.
In practice
Marked on deck by deck cadets with paint or tape during port stay; OCIMF MEG4 recommends marking the actual snap-back path rather than a generic arc. Crew briefed before each mooring operation that no one stands inside the marked zone during line-handling.
Regulatory detail & full definition
OCIMF MEG4 (2018) replaced the old fixed snap-back zone markings (often inaccurate) with a 'snap-back hazard area' covering the entire mooring deck — every line is treated as a potential snap-back source. Crew working mooring lines must keep all body parts out of the bight and direct line of fall. Required marking under MLC 2006 Reg. 4.3 + ISM Code Element 6.
Authoritative source: OCIMF MEG4 ↗
Related
Source: OCIMF Mooring Equipment Guidelines (MEG4) 2018
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