1) A vessel underway; astern; 2) a vessel at anchor; less than 50 metres; 3) a sailing vessel less than 7 metres or vessel under oars; 4) power-driven vessel; less than 7 metres, speed does not exceed 7 knots; 5) power-driven vessel; less than 50 meters in distance 2 β 5 miles.
in COLREG - 72