NIMASA STCW Tanker Familiarization cheat sheet

Oil tanker cargo is petroleum in bulk; chemical tanker cargo is liquid chemicals in bulk; liquefied gas tanker cargo is liquefied gas in bulk, carried at low temperature and/or under pressure.

Crude oil carriers commonly use inert gas and crude oil washing; product carriers carry refined products and often need segregated cargo systems and tank cleaning between grades.

Chemical tankers are defined by IBC Code ship types 1, 2 and 3, reflecting the hazard of the cargoes they may carry; type 1 is the most severe.

Liquefied gas carriers are defined by IGC Code ship types 1G, 2G and 3G, reflecting the hazard of the cargoes they may carry; 1G is the most severe.

Gas carrier containment systems include independent tanks (Type A, B, C), membrane tanks and internal insulation tanks; Type C is a pressure vessel designed for pressure and low temperature.

Chemical tanker cargo containment uses integral tanks, independent tanks or gravity tanks, with coatings or stainless steel to suit cargo corrosivity.

Oil tankers are commonly described by deadweight, cargo tank arrangement (centre and wing tanks) and whether they are double-hulled; MARPOL Annex I requires double hulls for new oil tankers.

Combination carriers (OBO, OO) can carry oil, bulk or ore; their cargo hold and piping arrangements create specific hazards during cargo changeover.

Flammability is characterised by flashpoint, auto-ignition temperature and flammable range (lower and upper explosive limits); a concentration between LEL and UEL can ignite.

Flashpoint below 60 degrees Celsius (closed cup) is the general threshold for a flammable liquid; cargoes with lower flashpoints present greater fire hazard.

Health hazards include acute toxicity, corrosivity, irritation, sensitisation and long-term effects; consult the SDS and the IBC/IGC Code data sheets.

Cargo hazards also include reactivity, self-reaction, polymerisation, and reaction with water, air or other cargoes; segregation rules prevent unsafe mixtures.

Safety culture is reflected in reporting near misses, following permit-to-work and enclosed space entry procedures, and stopping unsafe work without fear of blame.

Human factors such as fatigue, complacency and poor communication are recurring causes of tanker incidents; toolbox talks and pre-job briefings address these.

A hazard is a potential source of harm; risk is the combination of likelihood and severity of harm; control measures reduce risk to as low as reasonably practicable.

STCW Convention sets minimum standards for training, certification and watchkeeping; tanker familiarization is required for seafarers on tankers and is supplemented by advanced tanker training for officers.

MARPOL Annex I covers oil pollution, Annex II noxious liquid substances in bulk, Annex III harmful substances in packaged form, Annex IV sewage, Annex V garbage and Annex VI air pollution.

SOLAS covers ship construction, fire protection, life-saving appliances, radio communications and the ISM Code for safe management.

ISGOTT provides guidance for oil tanker and terminal safety, including ship/shore safety checklists, cargo operations and inert gas practice.

The IBC Code governs chemical tankers and the IGC Code governs liquefied gas carriers, setting design and equipment requirements for cargo hazard.

National requirements, such as flag State and port State regulations, may add to or exceed international conventions and must be followed in addition.

The ISM Code requires a Safety Management System with documented procedures, designated person ashore and emergency preparedness arrangements.

Certificates such as the International Oil Pollution Prevention Certificate and the Certificate of Fitness for chemical and gas carriers document compliance.

The Shipboard Oil Pollution Emergency Plan (SOPEP) is required under MARPOL Annex I and sets out response actions and reporting to authorities.

Emergency procedures typically cover fire, collision, grounding, cargo spill, personnel injury, enclosed space rescue and abandon ship, with muster lists and drills.

Drills and exercises must be conducted at intervals required by SOLAS and recorded; they test alarm response, communication and equipment readiness.

Emergency shutdown (ESD) systems stop cargo transfer and isolate the ship from the shore in a hazardous situation; the ESD sequence should be agreed at the ship/shore meeting.

Reporting of pollution incidents follows the SOPEP and local requirements, notifying the port authority, coast guard and flag State as appropriate.

Emergency teams are assigned roles such as fire team, first aid team and boundary cooling; the muster station and duties are posted on the muster list.

Contingency planning includes identifying escape routes, emergency lighting, breathing apparatus availability and the location of safety equipment.

Ignition sources on deck include smoking, naked flames, non-certified electrical equipment, hot work, sparks from tools and internal combustion engine exhausts.

Static electricity builds up during loading and from flow, filtration and water mist; bonding and grounding the ship to shore, and reducing flow rate at start, limit the risk.

Inert gas is used to keep cargo tank oxygen content low, typically below 8 percent by volume, to prevent flammable mixtures; inert gas must be maintained during cargo operations.

Toxic cargoes require monitoring of the atmosphere, supplied-air or self-contained breathing apparatus, and exclusion of personnel from contaminated areas.

Before entry into an enclosed space, the atmosphere must be tested for oxygen, flammable gas and toxic gas, and a permit-to-work must be issued.

Personal gas detectors and fixed gas detection systems should be calibrated and tested; alarms should be responded to immediately.

Static accumulator cargoes (low conductivity) require a settling period after loading before sampling or dipping, and sampling equipment must be bonded.

MARPOL Annex I prohibits discharges of oil except under strictly defined conditions, including limits on oil content and distance from land.

Oil Record Book entries must be made for ballasting, cleaning, discharge and disposal of oily residues; entries must be accurate and signed.

MARPOL Annex II controls discharge of noxious liquid substances and requires a Cargo Record Book and procedures for tank washing and disposal.

MARPOL Annex V prohibits discharge of garbage into the sea except for permitted categories; garbage must be segregated and recorded in the Garbage Record Book.

MARPOL Annex VI limits sulphur content of fuel oil and regulates emissions of nitrogen oxides and ozone-depleting substances, with requirements for the sulphur cap.

Ballast water management is regulated by the Ballast Water Management Convention to prevent transfer of invasive aquatic species.

Shipboard contingency plans and pollution prevention equipment, such as oil-water separators and containment booms, support response to spills.

Before cargo operations, a ship/shore safety checklist is completed and a pre-transfer meeting confirms cargo, rates, pressures, communications and emergency signals.

Cargo operations require continuous watch, monitoring of tank levels and pressures, and agreed communication between ship and shore.

Line clearing and draining must be done to prevent overpressure or spillage, and valves must be correctly set before starting transfer.

Cargo tank cleaning and gas freeing follow procedures to avoid flammable or toxic atmospheres; crude oil washing requires inert gas and specific procedures.

Chemical tanker cargo segregation prevents dangerous reactions; incompatible cargoes must be separated by cofferdams or distance according to the IBC Code.

Loading rates and line velocities are controlled to limit static generation and pressure surges; the maximum rate is agreed with the terminal.

Cargo sampling and gauging are done with closed or restricted equipment where required, and tank openings are kept closed during operations.

Liquefied gas cargoes are carried at low temperature, under pressure or both; cargo tanks must be kept within design pressure and temperature limits.

Cargo containment and insulation must be monitored for boil-off gas, and reliquefaction or burning of boil-off gas is managed to control tank pressure.

Low-temperature cargoes require protective clothing and care to avoid cold burns; materials must be suitable for cryogenic temperatures.

Cargo transfer involves vapour return lines and pressure control; the ship/shore interface must agree on vapour return and emergency shutdown.

Gas detection and inert gas or dry air padding are used to prevent flammable mixtures, depending on the cargo and containment system.

Loading and discharge rates are limited by the containment system and the terminal; rapid changes can cause thermal stress or pressure excursions.

Cargo tank atmosphere control and sampling are required before entry or maintenance, with the atmosphere tested for oxygen, flammable gas and toxicity.

PPE on tankers includes protective clothing, safety helmet, safety shoes, gloves, eye protection and, where required, breathing apparatus and chemical suits.

Life jackets and immersion suits are required for abandon ship and man overboard situations, and their location is shown on the muster list.

Personal gas detectors, escape sets and resuscitation equipment should be available and checked before use in hazardous areas.

Enclosed space entry requires a permit, atmosphere testing, a standby person and rescue equipment; never enter alone or without authorization.

Working at height, over the side or in machinery spaces requires risk assessment, permits and appropriate fall protection.

Fatigue and alcohol or drug impairment increase accident risk; rest hours and fitness for duty are regulatory and safety requirements.

Handling of chemicals and cargo samples requires use of SDS information, correct labelling and immediate cleanup of spills.