Officer on watch Duties – Knowledge Of Sea (2024)

Duties of an Officer on Watch (OOW) on the bridge

The primary duties of an Officer on Watch are:

(i) Watchkeeping,

(ii) Navigation and

(iii) GMDSS radio watchkeeping.

Officer on Watch is a representative of the master and is primarily responsible at all times for the safe navigation of the ship and for complying with COLREGS. As Officer on Watch, he is in charge of the bridge team for that watch, until properly relieved of his duty. The Officer on Watch shall ensure that master’s standing orders are fully complied with and bridge watch manning levels are safe at all times under prevailing circ*mstances and conditions.Watchkeeping duties include but are not limited to the following:

• maintaining a proper look out and general surveillance of the ship;

• collision avoidance in accordance with COLREGS;

• recording bridge activities and making periodic checks on all navigational equipment in use;

• follow procedures for handing over watch as per shipboard operation procedures;

• calling for support on the bridge as and when required;

• execute the passage plan safely and monitor the progress;

• maintain continuous GMDSS radio watch including distress signals if any;

• be conversant thoroughly with the speed, handling characteristics, stopping distances and turning circle of the ship;

• must not hesitate to use helm, engines or sound signalling apparatus at any time;

• must be fully conversant with all safety equipment on board and their usage particularly with reference to prevention of pollution and emergency situations;

• should not leave the bridge unattended at any time.

There are additional duties for the Officer on Watch that will be entrusted to him depending on his rank. He must be fully familiar with them e.g. cargo monitoring, general communications, control of machinery, supervision and control of safety systems etc. These additional duties must not interfere with the primary duties of the Officer on Watch.

Maintaining a lookout

COLREG places a mandatory provision for keeping a proper lookout on ship at all times. It must serve the following purpose:

• maintaining a continuous state of vigilance by sight and hearing as well as by all other available means in order to assess any significant change in the operating environment;

• appraising at all times the risk of collision, stranding and other dangers to navigation;

• detecting ships or aircraft in distress, shipwrecked persons, wrecks, debris or other hazards to safe navigation.

Lookout duties cannot be shared with other works e.g. a helmsman on duty, while steering should not be considered a lookout man unless the ship is small and he has the unobstructed all round view from the steering position.

Ships with fully enclosed bridges should have such provisions that sound reception from all audible sounds on the open deck is clear at all times inside the bridge.

Special precautions are to be taken by the OOW

The OOW must maintain a very high level of general awareness of day-to-day operation of the ship. It will include general watch over the ship’s decks to monitor, where possible people working on deck, and any cargo or cargo handling equipment. Special care and additional watches are to be kept in places where there is risk of piracy or armed attack.

Whenever people are working aloft or in the vicinity of radar antennae, radio aerials and sound signalling apparatus, the OOW should be particularly observant. Warning notices are to be posted at appropriate places and all concerned should be informed to take adequate precautions and inform the OOW once the assigned work is completed.

OOW compliance with the provisions of the COLREGS

Compliance of the provisions of the COLREGS means not only the conduct of the vessels under steering and sailing rules, but displaying the correct lights, shapes and making the correct sound and light signals. Vessels may not be displaying their correct lights/ shapes or the lights/ shapes may not be visible due certain restrictions of the ship’s structure when approached from a certain direction. It is therefore always prudent to allow extra searoom as long as it is safe to do so.

In all cases early and positive action should be taken when close quarter situation exists and to avoid collision. Once an action is taken the OOW must ensure that the action so taken has the desired effect. Valuable time should not be wasted in trying to contact the other vessel seeking collision avoidance action from the other party. It is not possible to have confirmed and positive identification of the other party and even so misunderstanding in communication could arise leading to disastrous results.

Risk of collision in a clear weather can be detected by taking frequent compass bearings of the other approaching vessel/s. If the bearings are study risk of collision exist. However risk of collision may still be there when approaching very large ships, ships under tow or ships at close range even when there is an appreciable bearing change.

In restricted visibility radar and radar plotting can be effectively used to assess risk of collision. However over reliance on electronic gadgets can be dangerous and the OOW should take every opportunity in clear weather to practice radar plotting and check and improve on his efficiency.