COLREG Rule 6 — Safe Speed
Every vessel shall proceed at a safe speed so she can take proper and effective action to avoid collision.
In practice
OOW reduces speed in restricted visibility, in heavy traffic, and around hazards. Pilots and masters often disagree about safe speed; the master's overriding authority applies.
Regulatory detail & full definition
COLREG Rule 6 — Safe Speed: 'Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions.' The rule lists the factors to be considered including state of visibility, traffic density, manoeuvrability, background lights, sea state, weather, and (for radar-equipped ships) the characteristics and limitations of the radar equipment. Safe speed is contextual; the open-ocean cruise speed is rarely safe in fog or restricted waters.
Authoritative source: COLREG 1972 ↗
Related
Source: COLREG 1972 Rule 6
High confidence
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