Traffic Separation Scheme (TSS) (TSS)

A formally adopted routeing measure that separates opposing or crossing streams of vessel traffic into defined lanes and associated areas.

A TSS can include traffic lanes, a separation line or zone, inshore traffic zones, precautionary areas and recommended directions. IMO-adopted schemes and their charted details are governed by the applicable collision-rule provisions, particularly Rule 10. A scheme organises traffic but does not remove collision risk or give vessels in a lane unrestricted priority. Entry, crossing, joining, leaving, fishing, anchoring and use of inshore zones have specific requirements, and lookout, safe speed and the other steering and sailing rules still apply.