SOLAS 1974 — Safety of Life at Sea
The single most important international treaty for the safety of merchant ships. Interactive deep-dives into Fire Fighting (II-2), Personal Survival (III), GMDSS (IV), Safety of Navigation (V) and SAR — plus a full 14-chapter compliance walkthrough for Flag State and Port State inspections.
Welcome to the audio journey of SOLAS — the Safety of Life at Sea Convention.
From the Titanic to today
Adopted after the 1912 Titanic disaster and re-enacted in 1974 with the tacit-acceptance amendment procedure, SOLAS is the cornerstone treaty governing the construction, equipment and operation of ships. 14 chapters cover everything from hull subdivision to polar operations.
The five chapters every seafarer must master
Click through each tab to explore the SOLAS chapters that dominate STCW competence assessments, ISM internal audits and PSC inspections worldwide.
1. The Fire Tetrahedron
The modern Fire Tetrahedron adds a fourth face — the uninhibited chemical chain reaction — to the classical triangle. Click any face to remove it and see how that element is suppressed.
Hot-work permits, low-flame surfaces, separated fuel & ignition, oily-rag bins.
Smoke/heat detectors, manual call points, sample-extraction in cargo holds, alarm to bridge.
Fire main, fixed CO₂ / water-mist / foam, portable extinguishers, fireman's outfits, EEBDs.
2. Classes of fire — A, B, C, D, E, F
Each class has a specific fuel chemistry and a matching extinguishing agent. Picking the wrong agent makes the casualty worse — sometimes catastrophically.
Flammable liquids (HFO, diesel, lube oil, paint, solvents)
Hydrocarbon liquids — primary engine-room and tanker risk.
- • Foam (AFFF) — vapour seal
- • CO₂
- • Dry powder (PKP)
- • Water mist
- • Solid water jet (spreads burning oil)
3. Gas fires — LPG / LNG / IGC drill
Step through the IGC / IGF Code response on a gas carrier — the order of actions is what matters most.
🚨 Gas leak ignited on deck (LPG/LNG carrier)
A jet flame is venting from a manifold flange. What is your FIRST action?
4. Class D — Metal fires
Class D — Metal Fires
Magnesium swarf · Aluminium dust · Sodium · Titanium · Lithium-ion batteries
Hot metal + H₂O → metal oxide + H₂ gas → violent explosion. Magnesium burns at 2200 °C and will strip oxygen from the water molecule itself.
Burning metals reduce CO₂ to elemental carbon — the fire grows hotter, not smaller.
- • Class-D powder (graphite-based G-Plus, NaCl-based Met-L-X) — smothers and absorbs heat.
- • Dry sand — emergency smothering when nothing else is available.
- • Isolate combustible metal stowage from the seat of fire; cool surrounding structure with water spray only when no metal is exposed.
- • Lithium-ion (EV cars, battery rooms): copious water for cooling and thermal-runaway control IS now accepted (the cell chemistry is different) — but only with crew at safe distance and isolation of electrics.
5. Breaking the chemical chain reaction
Breaking the chain reaction
Combustion is sustained by free radicals (H•, OH•, O•) that propagate the reaction faster than heat alone can drive it. The 4th extinguishing principle is to chemically interrupt these radicals.
6. SOLAS Ch II-2 Requirements — Equipment by Ship Type
Chapter II-2 + FSS Code — the layered defence
SOLAS Chapter II-2 (Fire protection, detection and extinction) is implemented through the Fire Safety Systems (FSS) Code and the Fire Test Procedures (FTP) Code. The strategy is defence-in-depth: structural fire integrity (A/B/C class), early detection, fixed and portable extinction, personal protective equipment, and continuous drills. The specific requirements depend on ship type, gross tonnage and the space being protected.
1. Equipment & Systems — by Category
2. Requirements by Ship Type
3. Structural Fire Protection — A / B / C Class Divisions
Prevents flame & smoke for 60 min; un-exposed side ≤140 °C avg / 180 °C peak.
Prevents flame passage for 30 min; lower thermal limits.
Limited spread of flame only; cabins to corridors, etc.
Boundaries are determined by the FTP Code (MSC.307(88)) tests and shown on the Fire Control Plan (Reg II-2/15.2.4) posted at both ends of the accommodation.
4. Fire Drill & Maintenance Schedule (Reg II-2/15, II-2/14)
| Frequency | Drill / Maintenance | Applies to |
|---|---|---|
| Within 24 h of joining | Familiarization with fire alarm, muster, fire control plan, escape routes | All new joiners |
| Weekly | Fire alarm + GA test; emergency fire pump start; check all extinguishers in place | All ships |
| Monthly | Fire drill with at least one scenario; rotate crew & locations; record response time | All ships |
| Monthly | Inspect all portable extinguishers; check SCBA pressure ≥80% | All ships |
| Quarterly | Test fixed gas/foam system controls (NO discharge); test detection loops | All ships |
| Annually | Service portable extinguishers; weigh CO₂ cylinders (±10%); full fire-main pressure test | All ships |
| Every 2 years | Boundary cooling drill simulating ER fire; fireman's outfit donning timed | Cargo & passenger |
| Every 5 / 10 years | CO₂ cylinder hydraulic test (10 y); SCBA cylinder hydraulic test (5 y) | All ships |
First-Response Mnemonic — "RACE-PASS"
The SOLAS Codes Library — all mandatory codes in one place
SOLAS is the parent treaty; the technical 'how' lives in dozens of subsidiary codes. Each card below briefly explains the code, illustrates its scope, and lists what a prudent deck officer or engineer must do daily to stay compliant. Filter by chapter.
International Life-Saving Appliance Code
Sets the international performance, construction and testing standards for every life-saving appliance: lifejackets, immersion suits, lifebuoys, lifeboats, liferafts, rescue boats, MES, line-throwing apparatus, EPIRBs and SARTs.
- Verify SOLAS marking, expiry stickers and last service date on each LSA item before signing the weekly inspection.
- Confirm HRU, EPIRB battery and pyrotechnics expiry dates appear in the planned maintenance system.
- Conduct lifeboat lowering to embarkation deck monthly and a full launching every 3 months (Reg III/19).
- Ensure davit limit switches, brakes and on-load release gear are greased and tested per LSA Code Ch VI.
- Lifeboat engine: start test weekly ahead/astern; check fuel oil/coolant levels and seawater pump priming.
International Code for Fire Safety Systems
The technical 'how' for every fire safety system referenced by SOLAS II-2: fire main, fixed CO₂/water-mist/foam, detection & alarm, fixed gas analysers in tankers, fireman's outfits, EEBDs, low-location lighting and helicopter-deck arrangements.
- Test general alarm and PA from each station weekly; log on the fire equipment register.
- Inspect fire-control plans (in the wheelhouse and weatherproof box outside accommodation) for currency.
- Run fire drill weekly on passenger ships, monthly on cargo ships, within 24 h of ≥25% crew change.
- Weigh / level-check CO₂ bottles per FSS Ch 5 (loss > 5% = recharge).
- Verify fire pump capacity and emergency fire pump independent start at every PMS interval.
- Maintain quick-closing valves, ventilation flaps and oil-mist detectors on Cat-A machinery space.
International Code for Application of Fire Test Procedures
Standard fire-test procedures for non-combustible materials and structural fire divisions — defines A-60, A-30, A-15, A-0, B-15, B-0 and C-class divisions used throughout SOLAS II-2.
- Confirm any new insulation, panel, curtain or upholstery installed has an FTP type-approval certificate retained onboard.
- Never penetrate an A-class division without an approved fire-rated penetration sleeve.
International Maritime Dangerous Goods Code
Classifies, packages, marks, labels, stows and segregates dangerous goods in packaged form. 9 hazard classes, UN numbers, EmS and MFAG emergency response.
- Cross-check the DG manifest against the stowage plan and segregation table before sailing.
- Verify placards, marks and Container Packing Certificate before accepting a unit.
- Brief duty officers on EmS code(s) and have MFAG on the bridge for declared cargoes.
International Maritime Solid Bulk Cargoes Code
Mandatory for all solid bulk cargoes. Splits cargoes into Group A (may liquefy — TML/MC), Group B (chemical hazards) and Group C (not liable to either). Includes shipper's declaration, BLU Code reference and trimming requirements.
- Require an accurate Shipper's Declaration with moisture content vs TML for Group A (concentrates, fines, nickel ore).
- Refuse loading if visible moisture or 'can test' fails — liquefaction has sunk many bulkers.
- Monitor hold atmospheres for Group B (e.g. coal — methane, self-heating, O₂ depletion).
International Code for the Safe Carriage of Grain in Bulk
Governs stability when carrying grain in bulk. Requires Grain Loading Booklet and Document of Authorization, calculating assumed heeling moments from grain shift in full and partly filled holds.
- Use only the approved Grain Loading Booklet; secure partly filled holds (strapping, bagging or saucering).
- Submit Grain Loading Plan to surveyor before loading — calculation must show residual GM after heel.
Code of Safe Practice for Cargo Stowage and Securing
Principles for stowing and securing all cargoes other than solid/liquid bulk. Basis of every ship's Cargo Securing Manual (CSM). Annexes for containers, wheeled cargo, heavy items and cargo carried at deck.
- Follow the approved CSM exactly — additional lashings on heavy-weather routes (Annex 13 calculation).
- Inspect lashings within 24 h of departure and after heavy weather; record in the deck log.
International Bulk Chemical Code
Design, construction and equipment standards for ships carrying dangerous liquid chemicals in bulk. Defines ship type 1/2/3 by cargo hazard, segregation, gauging, vapour return and emergency cargo jettison.
- Verify the Certificate of Fitness lists every cargo you plan to load — non-listed = refuse.
- Check P/V valves, vapour return manifolds, inert gas/N₂ blanket and tank-cleaning compatibility.
- Maintain inert gas / nitrogen plants per IBC Ch 9; oxygen analyser calibration before each operation.
- Test cargo pump emergency stops and high-level alarms before every load/discharge.
International Gas Carrier Code
Construction and equipment of ships carrying liquefied gases (LNG, LPG, ethylene, ammonia) in bulk. Cargo containment systems Type A/B/C/membrane, secondary barrier, gas detection, ESD.
- Pre-arrival: confirm ESD link test with shore, gas detection calibration, cargo-tank pressure & temperature in range.
- Maintain custody-transfer documentation and IGC-required compatibility/handling information for cargo.
- Reliquefaction plant / BOG management routines current; safety valve set pressures verified.
- Cargo machinery space ventilation 30 air-changes/hr; gas alarms tested daily.
International Code of Safety for Ships using Gases or Other Low-flashpoint Fuels
Mandatory since 2017 for ships burning LNG, methanol and other low-flashpoint fuels (extending soon to ammonia/hydrogen). Covers fuel containment, bunkering, double-walled piping, ESD and crew training (STCW V/3).
- Bunker only with an approved Bunker Delivery Note, ship-shore safety checklist and ESD link in place.
- Crew must hold STCW V/3 basic (and advanced for officers) training certificates.
- Gas valve unit (GVU) leak test before each transfer; double-wall annular space ventilation verified.
- Cryogenic PPE for LNG operations; never isolate ESD chain without permit.
Code for the Safe Carriage of Irradiated Nuclear Fuel etc.
Classifies ships carrying packaged irradiated nuclear fuel, plutonium and high-level radioactive wastes (INF 1/2/3) and adds damage stability, fire protection, temperature control and emergency planning requirements.
- Carry an approved Shipboard Emergency Plan and notify coastal/port states per the route radiological plan.
International Safety Management Code
Establishes the Safety Management System (SMS) bridging shore and ship: Company DOC, Ship SMC, Designated Person Ashore (DPA), risk assessment, master's review, NCR/CAR cycle, drills and audits.
- Master's annual SMS review on file; raise NCRs/observations through the company without fear.
- All shipboard operations covered by a written procedure — follow it or formally deviate (Risk Assessment).
- Critical equipment list maintained; test routines for emergency generator, fire/bilge pumps, steering gear.
- Permit-to-Work (hot work, enclosed space, electrical isolation, working aloft) signed before any non-routine job.
International Ship and Port Facility Security Code
Post-9/11 security regime: Ship Security Plan (SSP), CSO/SSO, Declaration of Security, ISSC, last-10-ports record, SSAS, drills every 3 months, exercises annually.
- Maintain access control, restricted-area marking and visitor log at all times.
- Match operating security level to coastal state; raise to Level 2/3 immediately when notified.
International Code of Safety for High-Speed Craft
Applies to HSC built on/after 1 July 2002 (the 1994 HSC Code applies to earlier craft). Route-specific Permit to Operate, Category A/B passenger craft, special crew training and operational manuals.
- Verify Permit to Operate covers today's exact route, wave height and visibility envelope.
- Crew hold HSC Type Rating; daily 'pre-departure' equipment checklist completed.
International Code for Ships Operating in Polar Waters
Two parts: Part I-A (safety, mandatory under SOLAS XIV) and Part II-A (environment, under MARPOL). Polar Ship Certificate (Cat A/B/C), Polar Water Operational Manual (PWOM), STCW V/4 ice training for officers.
- PWOM onboard, customised to the voyage; PST (Polar Service Temperature) respected for all equipment.
- Ice navigator on bridge in ice; LRIT, satellite comms and EPIRB tested for polar functionality.
- Heated sea-chests, anti-icing arrangements, low-temperature fuel & lube oil grades in service.
- Increased survival craft & immersion suit capacity per Polar Code Ch 8 (5-day expected rescue time).
International Code on Intact Stability
Mandatory intact stability criteria for all ships ≥24 m: minimum GM, area under GZ curve, angle of maximum GZ, weather criterion, plus special criteria for passenger ships, OSVs, fishing vessels and grain.
- Use the approved stability booklet / loading computer for every condition; never sail outside the approved envelope.
- Recalculate after every change in tanks, ballast or significant deck cargo.
Enhanced Survey Programme Code
Mandatory close-up surveys, thickness measurements and tank testing for oil tankers (single/double hull) and bulk carriers. Survey plan, condition evaluation report (CER), thickness diminution criteria.
- Survey Plan agreed with class 6 months before renewal; enclosed-space safe-entry permits before each hold/tank inspection.
- Address corrosion / coating breakdown findings before next loaded voyage.
IMO Instruments Implementation Code
Audit standard for IMO Member State Audit Scheme — defines Flag, Port and Coastal State obligations. Underpins every SOLAS, MARPOL, STCW and Load Line responsibility.
- Ship's documentation supports the Flag's audit evidence: surveys, casualty reports, PSC follow-up.
ISM & ISPS — the two codes that underpin every PSC inspection
The Safety Management System (ISM) and the Ship Security Plan (ISPS) are the only two codes a Port State Control Officer can use to detain a ship for systemic — not just technical — failure. Master both.
ISM Code — International Safety Management Code
Adopted 1993, mandatory under SOLAS Ch IX since 1998. The Code translates the Herald of Free Enterprise, Scandinavian Star and Estonia lessons into a structured, auditable Safety Management System (SMS) bridging shore office and ship. Without a valid DOC and SMC, the ship cannot legally trade.
- • Verify SMS procedures are followed; record deviations with risk assessment.
- • Sign Master's Standing Orders and Night Orders nightly.
- • Hold monthly Safety Committee — minute every action item.
- • File Annual Master's Review of the SMS (Element §5).
- • Raise NCRs to the DPA without fear — protected reporting culture.
- • Maintain Critical Equipment register — alternative arrangements when down.
- • Permit-to-Work signed before hot work, enclosed-space entry, electrical isolation, working aloft.
- • PMS jobs closed on schedule; overdue items in risk register.
- • Monthly drill: emergency generator black-start, emergency fire pump, steering gear changeover.
- • Bunker / sludge / oily-water transfers logged with risk-assessed checklists.
ISPS Code — International Ship & Port Facility Security
Adopted December 2002 after 9/11, in force July 2004. Two parts: Part A (mandatory) and Part B (recommendatory but adopted as mandatory by most Flag States). Built around three pillars: the Ship Security Assessment (SSA), the Ship Security Plan (SSP), and the International Ship Security Certificate (ISSC).
Minimum protective measures maintained at all times. Routine access control, ID check, search of unattended bags, restricted-area patrols.
- Single access point manned; ID check 100% of visitors.
- Restricted areas locked and signed.
- Random ≥10% screening of stores/baggage.
- Crew aware of suspicious-behaviour reporting.
- • Maintain Continuous Synopsis Record (CSR) — every change reported to Flag.
- • Last 10 ports record + ship-to-ship activities log up to date.
- • SSAS test quarterly with CSO — covert button positions known to Master/SSO only.
- • Drill every 3 months; full exercise within 18 months (or as Flag requires).
- • Match operating MARSEC level to coastal state — raise to 2/3 within minutes of notification.
- • Pre-arrival 96/24 h security notification (USCG NOA equivalent).
- • Annual review of SSA + SSP; resubmit for approval after any major change.
- • Maintain 24/7 contact roster; Flag, RSO, P&I, insurers, BMP/HRA cells.
- • Vet shore service providers, riding crews, and superintendents before each visit.
- • Cyber security risk management integrated since IMO Res. MSC.428(98).
- • Lessons learned from PSC ISPS deficiencies fed back to fleet via SMS.
LSA & FFA — additional animated illustrations
Every visual on this page belongs to the Deep Blue Maritime Visual System — a standardized illustration language used across the site.
Chapter III — Life-Saving Appliances
Chapter II-2 — Fire Protection
All 14 SOLAS chapters at a glance
Each panel summarises scope, key points, and what Flag State and Port State inspectors will look for. The five chapters explored above are marked 'Deep-dive'.
Flag State vs Port State — who does what?
Understanding the division of responsibilities is essential for any officer preparing for an inspection, audit or oral exam.
| Aspect | Flag State Control (FSC) | Port State Control (PSC) |
|---|---|---|
| Authority | Flag State of registry — primary responsibility under UNCLOS Art. 94 & SOLAS I/6. | Port State where ship calls — verification role under SOLAS I/19 + regional MoUs (Paris, Tokyo, Indian Ocean, etc.). |
| Frequency | Statutory survey cycle: initial → annual → intermediate (2½ yr) → renewal (5 yr). | Random; targeted by risk profile. Re-inspection on detention or 'clear grounds'. |
| Scope | Full construction, equipment, manning, SMS, security — issuance of certificates. | Certificates + condition check + operational drills (fire, abandon ship, steering test). |
| Outcome | Certificate issuance / withdrawal; recognised organisation (RO) acts on Flag's behalf. | Deficiencies, detentions, banning from MoU region. |
- All certificates valid and posted (in date order)
- Crew list, manning certificate, STCW endorsements current
- ISM SMC + DOC originals onboard
- ISPS — SSP, last 10 ports, SSAS test record
- Fire & abandon-ship drills logged within last week
- Lifeboat on-load release test record
- GMDSS radio log + battery capacity test
- ECDIS chart cells up to date
- Garbage Record Book + Oil Record Book entries complete
- Hours of rest / hours of work records compliant (MLC)
Study reminder: SOLAS is amended frequently through MSC resolutions (tacit acceptance). Always cross-check the latest consolidated edition (IMO IB110E) and applicable Unified Interpretations before an inspection or oral exam.