Iran Deck Officer (STCW II/2) Certificate of Competency Examination key terms

When two power-driven vessels meet on reciprocal or nearly reciprocal courses so as to involve risk of collision, each must alter course to starboard and pass port side to port side.

When two power-driven vessels cross so as to involve risk of collision, the vessel with the other on her own starboard side must keep out of the way and normally avoid crossing ahead of the stand-on vessel.

The give-way vessel must take early and substantial action to keep well clear; the stand-on vessel keeps course and speed but must act if collision cannot otherwise be avoided by the give-way vessel alone.

A situation assessed by using all available means, including radar plotting and compass bearing observation; a steady bearing with decreasing range indicates that risk of collision exists and requires action.

The speed at which a vessel can take proper and effective action to stop within a distance appropriate to the prevailing circumstances, including visibility, traffic density, draught, and stopping distance.

Continuous observation by sight and hearing and by all available means appropriate to the circumstances, maintained to make a full appraisal of the situation and the risk of collision.

Rules requiring vessels to keep to the starboard side of a narrow channel, avoid anchoring, and follow traffic lanes, separation zones, and inshore traffic zones in an adopted traffic separation scheme.

Two worldwide systems for lateral marks: Region A uses red to port and green to starboard when entering from seaward; Region B reverses this, with red to starboard and green to port.

Buoys and beacons indicating the safe side to pass by their direction from a hazard, using north, east, south, and west combinations of black and yellow colour and topmarks.

The low-water reference level from which depths and drying heights on a nautical chart are measured, normally lowest astronomical tide, so charted depths are minimum expected depths.

The predicted rise or fall of water at a standard port or secondary port, calculated from tide tables and adjusted for time and height differences to give the actual depth at a place and time.

The vertical distance between the lowest point of the vessel's hull and the seabed, allowing for squat, tide, swell, and chart accuracy, kept positive throughout the passage.

The reduction in under-keel clearance and increase in draught caused by water flow around a moving hull, greatest in shallow water and at higher speed, and larger for full-form vessels.

The tendency of a vessel to be drawn toward a nearby bank or toward another vessel in close proximity, causing sheering and loss of control in confined or shallow waters.

The distance a vessel travels from the order to stop engines until she is stopped through the water, including the time for engine response and the distance run during that time.

The system and procedure for transmitting and acknowledging propulsion orders between bridge and engine room, including emergency orders and the requirement to record orders and times.

Presentation modes in which own ship is fixed and targets move relative to her, or in which own ship moves across a stabilised display; each affects how risk of collision is assessed.

Automatic radar plotting aid functions that acquire targets, calculate course, speed, closest point of approach, and time to closest point of approach, and warn of collision risk.

A computer-based navigation system displaying official vector or raster charts with position, route, and safety settings, subject to type approval and backup arrangements under SOLAS.

Satellite positioning used for fixing position, vulnerable to jamming, spoofing, and outages; watchkeepers must cross-check satellite positions by independent means such as visual bearings and radar.

Two aligned marks or lights, or a bearing taken on two objects, that indicate the vessel is on a known line of position, used to confirm track and monitor cross-track error.

The position obtained by advancing a known position through the water using course and speed, corrected for current and leeway, used as a check on satellite or visual fixes.

The formal transfer of the navigational watch, including position, course and speed, traffic, weather, machinery status, and standing orders, confirmed by both officers before responsibility changes.

Written instructions from the master defining the conditions under which the officer of the watch must call the master or take action, reviewed and signed at the start of each watch.

Drills and procedures for steering gear failure, changeover to emergency steering, and the associated signals, communications, and speed reduction required under SOLAS.

The table or graph relating a vessel's mean draught to her displacement and deadweight, used to calculate loading limits and verify that load line and structural limits are met.

Marks on the ship's side showing the minimum permissible freeboard in different seasons and zones, assigned under the International Convention on Load Lines to preserve reserve buoyancy.

Trim is the difference between forward and aft draughts; list is a permanent transverse inclination caused by off-centre weight, both affecting stability, handling, and cargo distribution.

The distance between the centre of gravity and the metacentre; positive GM gives initial transverse stability, small GM gives a tender ship, and large GM gives a stiff, quick-rolling ship.

The loss of effective metacentric height caused by liquid moving freely in partly filled tanks, reducing stability; minimised by pressing up or emptying tanks and by longitudinal subdivision.

The requirement under the International Grain Code to limit heeling moments from grain shift, ensuring the angle of heel stays within permitted limits and stability remains adequate.

The ability of a ship to survive specified damage, assessed by subdivision, permeability, and floodable length, with the requirement to keep the margin line or permitted heel within limits.

A watertight bulkhead near the forward end designed to limit flooding after collision, part of a system of watertight doors, hatches, and closures that must be maintained and tested.

Movement of liquid or bulk cargo within a tank or hold due to ship motion, causing dynamic forces on structures and heeling moments; controlled by filling limits, baffles, and securing.

The rules of the IMDG Code governing classification, packing, marking, stowage, segregation, and documentation of dangerous goods, including the segregation table and special requirements.

The system of twistlocks, rods, and lashings that holds containers to the deck or to each other, checked against the cargo securing manual and stack weight limits before departure.

The approved document giving securing arrangements and the calculation of forces from ship motion, used to confirm that cargo will not shift and that lashings are adequate for the voyage.

Procedures and interlocks that prevent starting or running the main engine when the turning gear is engaged or the shaft is locked, avoiding serious damage to the propulsion plant.

Equipment required to treat bilge water so that discharges contain no more than 15 parts per million of oil, recorded in the oil record book under MARPOL Annex I.

Shipboard plans required by MARPOL giving procedures, equipment, and reporting arrangements for responding to oil pollution and for managing and recording garbage disposal.

Measures under the Ballast Water Management Convention to treat or exchange ballast to prevent transfer of harmful aquatic organisms, recorded in the ballast water record book.

The posted list assigning each crew member a station and duties for fire, abandon ship, and other emergencies, supported by regular drills and familiarisation training.

Fixed systems such as CO2, foam, and water spray, together with portable extinguishers and a posted plan showing fire boundaries and controls, inspected and maintained under SOLAS.

The permit and procedure requiring atmosphere testing for oxygen, hydrocarbons, and toxic gases, ventilation, standby personnel, and rescue equipment before entry into tanks or voids.

Distress alerting equipment and the Global Maritime Distress and Safety System, including digital selective calling, satellite communication, and the sea areas in which each is required.

The standardised vocabulary and phraseology used for navigation and safety communications, designed to reduce ambiguity in ship-to-ship and ship-to-shore exchanges.

The practice of using pressure, wind shifts, and swell to locate a tropical cyclone and alter course to keep clear of the dangerous semicircle and the storm's projected track.

A scale relating wind speed to observable effects at sea, used with wave height and period descriptions to report weather and assess conditions affecting navigation and cargo operations.

Inspection of foreign ships by port authorities for compliance with conventions, and the flag State's duty to survey, certify, and ensure that its ships meet international requirements.

The International Safety Management Code requires a documented safety management system covering policy, procedures, emergency preparedness, and internal audit, verified by certification.

The standards for training, certification, and watchkeeping, including sea service, examination, medical fitness, and rest-hour limits required to serve as officer of the watch or master.