Rule 10

Traffic Separation Schemes.

(a) This Rule applies to traffic-separation schemes adopted by the Organization, and does not relieve any vessel of her obligation under any other rule.

(b) A vessel using a traffic-separation scheme shall:

(i) proceed in the appropriate traffic lane in the general direction of traffic flow for that lane;

(ii) so far as practicable keep clear of a traffic-separation line or separation zone;

(iii) normally join or leave a traffic lane at the termination of the lane, but when joining or leaving from either side shall do so at as small an angle to the general direction of traffic flow as practicable.

(c) A vessel shall, so far as practicable, avoid crossing traffic lanes, but if obliged to do so shall cross on a heading as nearly as practicable at right angles to the general direction of traffic flow.

(d) (i) A vessel shall not use an inshore traffic zone when she can safely use the appropriate traffic lane within the adjacent traffic-separation scheme. However vessels of less than 20m (66ft) in length, sailing vessels and vessels engaged in fishing may use the inshore traffic zone.

(ii) Notwithstanding subparagraph (d) (i), a vessel may use an inshore traffic zone when en-route to or from a port, offshore installation or structure, pilot station or any other place situated within the inshore traffic zone, or to avoid immediate danger.

(e) A vessel other than a crossing vessel or a vessel joining or leaving a lane shall not normally enter a separation zone or cross a separation line except:

(i) in cases of emergency to avoid immediate danger;

(ii) to engage in fishing within a separation zone.

(f) A vessel navigating in areas near the terminations of traffic-separation schemes shall do so with particular caution.

(g) A vessel shall so far as practicable avoid anchoring in a traffic-separation scheme or in areas near its terminations.

(h) A vessel not using a traffic-separation scheme shall avoid it by as wide a margin as is practicable.

(i) A vessel engaged in fishing shall not impede the passage of any vessel following a traffic lane.

(j) A vessel of less than 20m (66ft) in length or a sailing vessel shall not impede the safe passage of a power-driven vessel following a traffic lane.

(k) A vessel restricted in her ability to manoeuvre when engaged in an operation for the maintenance of safety of navigation in a traffic-separation scheme is exempted from complying with this Rule to the extent necessary to carry out the operation.

(l) A vessel restricted in her ability to manoeuvre when engaged in an operation for the laying, servicing or picking-up of a submarine cable within a traffic-separation scheme, is exempted from complying with this Rule to the extent necessary to carry out the operation.

A Traffic Separation Scheme (TSS) is marked very clearly on all relevant charts.  Several exist in north European waters, primarily to introduce motorway-style traffic control, for areas heavily populated by commercial shipping.

There are three very important parts of Rule 10.

The first is found in paragraph (a), which confirms that vessels using a TSS are not absolved of their responsibilities under the other Rules.  This means, that at the end of the day, the Steering and Sailing Rules still apply, when navigating within a TSS.  If there is another vessel crossing the TSS and it is on a steady bearing with the attendant risk of collision associated with this, then you still have to do something.  Just because you are in a TSS does not give you any rights, whatsoever.  There are some, who think that because they are in a TSS and have another vessel on their own Starboard side, they do not have to give way.  This is a totally false understanding of the regulations, as they are still obliged to give way, even if it means leaving the TSS for a short period of time.  Remember also, most TSS’s around the world are monitored by radar and you could subsequently receive a heavy fine or even be imprisoned with your livelihood taken away, should you infringe any of the rules in a TSS.

The second important point is found in paragraph (j), which clearly states that all craft under 20 metres (or 66 feet in length) must not impede power driven vessels following a traffic lane.  In practice, given the relative manoeuvrability of small craft, there is no reason why they should do so.  A vessel forced to make a course correction for a small vessel might in turn, come into conflict with another vessel in the same lane.

The third important point is paragraph (d).  Vessels of less than 20m in length, sailing vessels and vessels engaged in fishing are able to make coastal passages along inshore traffic zones and should encounter a TSS, only when crossing one.

The rule for crossing a TSS paragraph (c) is very simple: set a course, which is at 90 degrees to the flow of the traffic within the lanes.  You must NOT make any allowance for the tide in a TSS.  The aim is to provide an aspect, which is at right angles to the ships you are likely to encounter, not to achieve a track over the ground, which is 90 degrees to the charted lane. 

When approaching a TSS, you should be very careful as ships may not notice you or their intentions may not be detected in time. Collisions still occur between commercial ships, which in many instances can only have come about because of poor watchkeeping and/or poor visibility from the bridge.  Some of them even manage to hit large stationary objects, on a regular basis.

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