IMO Convention
SOLAS Convention
International Convention for the Safety of Life at Sea — the most important international treaty concerning the safety of merchant ships, governing construction, equipment and operations across 14 technical chapters.
History and Background
The first SOLAS treaty was adopted in 1914 in response to the sinking of the RMS Titanic in 1912. Successive versions were adopted in 1929, 1948, and 1960. The current convention was adopted on 1 November 1974 by a conference at IMO headquarters in London and entered into force on 25 May 1980.
Rather than adopting a new convention each time amendments are needed, a tacit acceptance procedure has been used since 1974 — amendments enter into force automatically on a specified date unless a sufficient number of contracting states object. This has allowed SOLAS to remain current with evolving maritime technology and safety thinking.
The 1974 convention has been substantially amended by protocols in 1978 and 1988, and by numerous MSC resolutions. The consolidated text (2020 edition) incorporates all amendments in force as of 1 January 2020 and is the definitive working reference for maritime administrations and flag states.
Chapter Summaries
| Chapter | Scope | Key Requirements | Recent Changes |
|---|---|---|---|
| Ch I | All SOLAS ships | General Provisions Surveys, inspections, certificates, port state control | Continuous Synopsis Record updates |
| Ch II-1 | Ships >500 GT (generally) | Construction, Structure, Subdivision & Stability Subdivision, damage stability, machinery, electrical installations | SOLAS-2020 harmonised stability requirements |
| Ch II-2 | All SOLAS ships | Fire Protection, Detection & Extinction Fixed fire detection, suppression systems, fire doors, structural fire protection | MSC.404(96) — public spaces fire protection |
| Ch III | All SOLAS ships | Life-Saving Appliances & Arrangements Lifeboats, liferafts, EPIRBs, SARTs, immersion suits, LSA maintenance | Free-fall lifeboat and rescue boat requirements updated |
| Ch IV | All SOLAS ships | Radio Communications GMDSS — VHF DSC, MF/HF DSC, NAVTEX, EPIRB, SART by sea area | MSC.436(99) — GMDSS modernisation, in force 1 Jan 2024 |
| Ch V | ALL ships on ALL voyages | Safety of Navigation Voyage planning, lookout, safe speed, AIS, ECDIS, VDR, LRIT, charts | MSC.282(86) — ECDIS performance standards |
| Ch VI | Cargo ships | Carriage of Cargoes Stowage, securing, grain loading, cargo information, VGM verification | Verified Gross Mass (VGM) requirements in force 2016 |
| Ch VII | Ships carrying dangerous goods | Carriage of Dangerous Goods IMDG Code, IGC Code, IBC Code, INF Code | IMDG Code Amendment 40-20 |
| Ch VIII | Nuclear-powered ships | Nuclear Ships Special safety requirements for nuclear propulsion | No recent amendments |
| Ch IX | Ships >500 GT on international voyages | Management for Safe Operation (ISM Code) SMS, DOC for company, SMC for vessel, DPA appointment | MSC-MEPC.7/Circ.8 — ISM Code guidance updated |
| Ch X | High-speed craft | Safety Measures for High-Speed Craft HSC Code 1994 and 2000 — construction, stability, firefighting | HSC Code periodic revision |
| Ch XI-1 | All SOLAS ships | Special Measures to Enhance Maritime Safety Enhanced surveys, ship ID number marking, CSR, AIS carriage | Continuous Synopsis Record (CSR) requirements |
| Ch XI-2 | Ships >500 GT international + port facilities | Special Measures to Enhance Maritime Security (ISPS) ISSC, SSP, SSA, company/ship/port security officers, MARSEC levels | MSC.1/Circ.1601 — cyber security guidance |
| Ch XII | Bulk carriers | Additional Safety Measures for Bulk Carriers Structural requirements, hold flooding detection, hatch covers | Ongoing bulk carrier survey requirements |
| Ch XIII | IMO Member States | Verification of Compliance (IMSAS) IMO Member State Audit Scheme — implementation verification | Mandatory as of 2016 |
| Ch XIV | Ships operating in polar waters | Safety Measures for Ships in Polar Waters Polar Code (mandatory) — ice class, cold/ice performance, LSA for polar | Polar Code in force 1 January 2017 (MSC.385(94)) |
Recent Amendments
| Year | Resolution | Subject | In Force Date |
|---|---|---|---|
| 2024 | MSC.496(105) | GMDSS Modernisation (Ch IV) — in force | 1 Jan 2024 |
| 2023 | MSC.471(101) | Amendments to Ch II-1 (watertight integrity) | 1 Jan 2024 |
| 2022 | MSC.459(101) | CIU — Carbon Intensity Indicator linkage | 1 Nov 2022 |
| 2021 | MSC.421(98) | Polar Code amendments — non-SOLAS ships | 1 Jul 2024 |
| 2020 | MSC.404(96) | Fire protection in public spaces (Ch II-2) | 1 Jan 2022 |
| 2018 | MSC.436(99) | GMDSS modernisation — Ch IV revised | 1 Jan 2024 |
| 2016 | MSC.380(94) | Verified Gross Mass (VGM) — Ch VI | 1 Jul 2016 |
| 2014 | MSC.349(92) | Polar Code adoption | 1 Jan 2017 |
Key SOLAS Certificates
| Certificate | Abbr | Validity | Issued by | Notes |
|---|---|---|---|---|
| Cargo Ship Safety Construction Certificate | CSSCC | 5 years | Flag State / RO | Covers structural, machinery and equipment requirements |
| Cargo Ship Safety Equipment Certificate | CSSEC | 5 years | Flag State / RO | LSA, FFA, navigation equipment |
| Cargo Ship Safety Radio Certificate | CSSRC | 5 years | Flag State / RO | GMDSS equipment for sea area |
| Cargo Ship Safety Certificate | CSSC | 5 years | Flag State / RO | Consolidated — combines construction, equipment, radio |
| Passenger Ship Safety Certificate | PSSC | 1 year | Flag State / RO | Annual survey required for passenger vessels |
| Document of Compliance | DOC | 5 years (annual endorsement) | Flag State | Issued to company — covers specific ship types |
| Safety Management Certificate | SMC | 5 years (intermediate survey at 2.5 yr) | Flag State / RO | Issued to individual vessel under ISM Code |
| International Ship Security Certificate | ISSC | 5 years (annual verification) | Flag State / RSO | Issued under ISPS Code (SOLAS Ch XI-2) |
| Continuous Synopsis Record | CSR | Lifetime of ship | Flag State | Historical record of flag, company, class, name changes |
| Minimum Safe Manning Certificate | MSM | As issued | Flag State | Sets minimum crew for safe operation under SOLAS V |