IALA Buoyage System B

IALA Buoyage System Region B is one of the two regional lateral-mark conventions in the IALA Maritime Buoyage System (Recommendation R1001), used in North, Central, and South America, Japan, Korea, and the Philippines. In Region B a vessel entering harbor keeps red conical starboard-hand marks on its right and green can-shaped port-hand marks on its left (the mnemonic: red right returning). This is the reverse of Region A, where red marks the port hand on entry. Only the lateral marks differ between regions; cardinal, isolated-danger, safe-water, and special marks carry the same shapes, colors, and topmarks worldwide. The two-region split exists because earlier national systems could not agree a single lateral color sense.