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Shipboard Operations

Practical Q&A for watchkeeping, safety, maintenance routines and onboard documentation.

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Current Answers

What should be checked during engine-room watchkeeping rounds?

How to make an engine-room round count — comparing live readings against normal ranges and catching trends before they become failures.

WatchkeepingBilgeLogbookPurifier

What is a toolbox talk and when is it done?

What a toolbox talk is, when it happens before shipboard work, and how it turns the risk assessment and permit into a shared plan.

Toolbox talkRisk assessmentPermit to workPPE

What must be checked before enclosed space entry?

The core precautions before entering an enclosed space — atmosphere testing, permit, ventilation, standby and communications — because these spaces still kill seafarers.

Enclosed spaceEntry permitOxygen contentStandby person

What are the key steps in a safe bunkering operation?

The essentials of safe bunkering — the agreed plan and checklist, scuppers and SOPEP readiness, communication, monitoring and verifying the figures.

BunkeringSOPEPScupperBunker delivery note

How do I prepare for a Port State Control inspection?

How to be ready for Port State Control — certificates, drills, maintenance evidence and housekeeping — so a routine inspection does not become a detention.

Port State ControlDetentionISM CodePlanned maintenance

What is the man overboard (MOB) procedure on a ship?

When someone falls overboard, immediate, drilled actions — raising the alarm, marking the position and turning the ship back — give the best chance of recovery.

Man overboardRescue boatGMDSSWatchkeeping

What is a permit to work (PTW) system on ships?

A permit to work is a formal written authorisation that controls hazardous, non-routine jobs by confirming the hazards are assessed and the right precautions are in place.

ISM CodeEnclosed spaceRisk assessmentHot work

What is an inert gas system on a tanker and why is it needed?

An inert gas system fills a tanker's cargo tanks with oxygen-poor gas so the atmosphere cannot support combustion, preventing explosions in and around the cargo.

TankerSOLASScrubberTank cleaning

What is a Shipboard Oil Pollution Emergency Plan (SOPEP)?

SOPEP is the Shipboard Oil Pollution Emergency Plan, a MARPOL-required plan that tells the crew how to report and respond to an oil spill from the ship.

MARPOLBunkerOily water separatorPort State Control

What are the SOLAS lifeboat and abandon ship drill requirements?

SOLAS requires regular abandon-ship and fire drills, with musters, equipment checks and the lowering and manoeuvring of lifeboats at defined intervals.

SOLASLife-saving appliancesMusterRescue boat

What is a snap-back zone and why is mooring so dangerous?

A snap-back zone is the area a mooring line may whip through if it parts under tension — mooring decks are among the most dangerous places on a ship.

MooringBerthRisk assessmentPilotage

What is a risk assessment on a ship and how is it done?

A shipboard risk assessment systematically identifies the hazards of a task, evaluates the risk and puts controls in place before the work begins.

ISM CodeRisk assessmentEnclosed spaceToolbox talk

What is a hot work permit and when is it needed?

A hot work permit controls any work involving heat, flame or sparks outside a designated safe area, confirming the space is gas-free and fire precautions are in place.

Hot workEnclosed spaceISM CodeTanker

What is the abandon ship procedure and when is it ordered?

Abandoning ship is the last resort when a vessel can no longer be saved — it follows a drilled sequence of muster, boarding survival craft and summoning rescue.

SOLASLife-saving appliancesEPIRBMuster

Why are enclosed spaces on ships so dangerous?

Enclosed spaces kill because their atmosphere can be oxygen-deficient, toxic or flammable with no outward sign — and rescuers who rush in become the next victims.

Enclosed spacePermit to workInert gasRisk assessment

What is the correct enclosed space rescue procedure?

Enclosed space rescue must never be attempted by rushing in — it demands raising the alarm and using a trained team with breathing apparatus and retrieval equipment.

Enclosed spaceBreathing apparatusPermit to workMuster

What is the procedure for anchoring a ship?

Anchoring safely means preparing the gear, approaching the chosen spot slowly against wind and tide, letting go with controlled cable, and keeping an anchor watch.

AnchorAnchorageWindlassPilotage

How is a navigation (bridge) watch properly handed over?

A bridge watch handover requires the relieving officer to be fully oriented — position, traffic, course and dangers — before accepting the watch, and never mid-manoeuvre.

WatchkeepingSTCWCOLREGSPassage planning

What are the four stages of passage planning (appraisal, planning, execution, monitoring)?

Passage planning follows four stages — appraisal, planning, execution and monitoring — that together prepare and carry out a safe voyage from berth to berth.

Passage planningECDISSOLASPilotage

What is a garbage management plan and what does MARPOL require?

A garbage management plan sets out how a ship collects, separates, stores and disposes of its garbage in line with MARPOL Annex V, which bans plastics disposal at sea.

MARPOLGarbage record bookPort State ControlSOPEP

How is cargo secured and lashed on a ship?

Cargo is secured against the forces of the ship's motion using lashings, twistlocks and dunnage, in accordance with the ship's approved Cargo Securing Manual.

Cargo securing manualContainer shipStabilityBreakbulk

How does marine radar and ARPA work?

Marine radar detects other ships and land by transmitting radio pulses and timing their echoes; ARPA automatically tracks targets and calculates the risk of collision.

AISCOLREGSECDISWatchkeeping

What is the difference between magnetic variation and deviation?

Variation is the angle between true and magnetic north caused by the Earth's field; deviation is the compass error caused by the ship's own magnetism. Together they make up compass error.

CompassGyrocompassNautical chartWatchkeeping

What is dead reckoning in navigation?

Dead reckoning is estimating a ship's present position from a known past position by applying the course steered and the distance run, without reference to external fixes.

Passage planningNautical chartCompassKnot

What is a gyrocompass and how does it differ from a magnetic compass?

A gyrocompass is a navigation instrument that uses a fast-spinning gyroscope to find and hold true north, unaffected by the ship's magnetism, providing a true heading to the ship's systems.

CompassECDISAISWatchkeeping

How do you read a nautical chart?

A nautical chart is a map of the sea showing depths, dangers, aids to navigation and the coastline, read using its scales of latitude and longitude, soundings, symbols and compass rose.

Nautical chartECDISPassage planningCompass

What is a draught survey and how is cargo weight calculated?

A draught survey determines the weight of bulk cargo loaded or discharged by measuring the ship's draughts and calculating the change in its displacement.

DraftDisplacementDeadweight tonnageBallast

What is crude oil washing (COW) on a tanker?

Crude oil washing cleans a tanker's cargo tanks during discharge by spraying them with the crude cargo itself, which dissolves clingage and reduces residue, sludge and pollution.

TankerMARPOLInert gasTank cleaning

How is a cargo tank cleaned on a tanker?

Cargo tanks are cleaned with fixed or portable washing machines using water or crude oil, followed by draining, gas-freeing and ventilation, before a change of cargo, entry or repair.

Tank cleaningInert gasEnclosed spaceMARPOL

How is ballast water managed and treated on board a ship?

Under the Ballast Water Management Convention, ships manage ballast water either by mid-ocean exchange or, increasingly, by treating it through an approved system before discharge.

BallastBallast Water Management ConventionBiofoulingPort State Control

What are the classes of fire and which extinguishers are used on ships?

Fires are grouped into classes by what is burning, and each class needs the right extinguishing agent — using the wrong one can be ineffective or dangerous.

Fire triangleSOLASCO2 floodingMuster

How does a fixed CO2 flooding fire-extinguishing system work?

A fixed CO2 system extinguishes a fire in a protected space such as the engine room by flooding it with carbon dioxide, which displaces the oxygen the fire needs — after everyone is evacuated.

CO2 floodingSOLASFire triangleEnclosed space

What is a muster list on a ship?

A muster list is the SOLAS-required document that assigns every crew member their duties and muster station for each emergency, and sets out the alarm signals.

MusterSOLASLife-saving appliancesLife-saving appliances

What precautions does a ship take in heavy weather?

In heavy weather a ship reduces speed and adjusts course to ease its motion, secures everything for sea, manages ballast and stability, and guards against dangerous rolling.

StabilityBeaufort scaleCargo securing manualPassage planning

What are safe pilot boarding arrangements and pilot ladder requirements?

Pilot boarding arrangements must let a pilot get on and off a moving ship safely, chiefly by a correctly rigged pilot ladder meeting SOLAS requirements, attended by an officer.

PilotageSOLASGangwayFreeboard

What is a Safety Management System (SMS) on a ship?

A Safety Management System is the documented set of policies and procedures, required by the ISM Code, by which a company manages the safe operation of its ships and prevention of pollution.

ISM CodeRisk assessmentPort State ControlMaster

What is a near miss on a ship and why is reporting it important?

A near miss is an event that could have caused injury, damage or pollution but happened not to — reporting them lets a ship correct hazards before they cause a real accident.

ISM CodeRisk assessmentToolbox talkSafety management system

What is lock-out tag-out (LOTO) and why is it used aboard ship?

Lock-out tag-out is the practice of isolating a machine's energy sources and physically locking and tagging them off before maintenance, so it cannot be started or energised while someone is working on it.

Permit to workISM CodeRisk assessmentEnclosed space

What safety precautions are taken for working aloft on a ship?

Working aloft — up the mast, funnel or high structures — demands a permit, a safety harness, secured tools, and control of hazards such as radar, whistle and overside work.

Permit to workRisk assessmentISM CodeMuster

What is bridge resource management (BRM) and why does it matter?

Bridge resource management is the effective use of all the people, equipment and information available on the bridge to navigate safely, reduce human error and prevent accidents.

WatchkeepingCOLREGSPassage planningPilotage

What is under keel clearance and why is it important?

Under keel clearance is the vertical gap between the lowest point of a ship's keel and the seabed — a safety margin that must be maintained to avoid grounding.

DraftSquat effectPassage planningNautical chart