International Maritime Organization (IMO)
Structure of conventions, codes, and protocols with key concepts for maritime training.
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IMO["🏛️ IMO
International Maritime Organization
Established 1948 · Headquarters: London
175 member states"] IMO -.->|"Mission: safe navigation,
protection of the marine environment,
competent seafarers"| MISION(["🌍 Safe navigation · Clean seas · Competent seafarers"]) IMO ==>|"governs"| ASAMBLEA["📋 Assembly
Supreme body · Meets every 2 years
Approves budget and resolutions"] IMO ==>|"directs"| CONSEJO["🏢 Council
Executive body · 40 members
Supervises between Assembly sessions"] IMO ==>|"administers"| SECRETARIA["📝 Secretariat
Coordinates technical work
~300 international officers"] CONSEJO ==>|"safety"| MSC["⚓ MSC
Maritime Safety
Committee
Main technical committee"] CONSEJO ==>|"environment"| MEPC["🌿 MEPC
Marine Environment
Protection Committee"] CONSEJO ==>|"maritime law"| LEG["⚖️ Legal Committee
Liability and
compensation"] CONSEJO -->|"capacity-building for
developing states"| TC["🎓 Technical
Cooperation Committee"] CONSEJO -->|"simplification of
formalities"| FAL["📄 Facilitation
Committee"] MSC ==>|"most important
maritime safety convention"| SOLAS["🛡️ SOLAS 1974
Safety of Life
at Sea
14 chapters · Mandatory"] MSC ==>|"maritime professional
competence"| STCW["📚 STCW 1978/2010
Training, Certification
and Watchkeeping
Manila Amendments 2010"] MSC ==>|"rules of the road
at sea"| COLREG["🚦 COLREG 1972
International Regulations
for Preventing Collisions
38 Rules + 4 Annexes"] MSC -->|"search and rescue
coordination"| SAR["🆘 SAR 1979
Search and
Rescue
Global SAR plan"] MSC -->|"protection against
unlawful acts"| ISPS["🔒 ISPS Code
Ship and Port Facility
Security
Post-9/11 · Mandatory 2004"] MEPC ==>|"most complete
environmental convention"| MARPOL["🌊 MARPOL 73/78
Prevention of Pollution
from Ships
6 technical annexes"] MEPC -->|"invasive species through
ballast water"| BWM["🦠 BWM 2004
Ballast Water
Management
In force since 2017"] MEPC -->|"toxic antifouling
paints"| AFS["🎨 AFS 2001
Anti-Fouling
Systems
Bans TBT"] LEG -->|"who pays for
oil spill damage?"| CLC["💰 CLC 1969/92
Civil Liability for Oil
Pollution Damage
Strict shipowner liability"] LEG -->|"supplementary fund when
CLC is not enough"| FUND["🏦 FUND 1992
International Compensation
Fund
Financed by oil receivers"] LEG -->|"maximum compensation
limit"| LLMC["📏 LLMC 1976/96
Limitation of
Liability
Based on vessel GT"] SOLAS ==>|"structure"| SOLAS_CAP["14 SOLAS Chapters"] SOLAS_CAP -->|"structure and
stability"| CAP_II["Ch. II-1/II-2
Construction · Subdivision
Stability · Fire protection"] SOLAS_CAP -->|"boats, rafts,
lifejackets"| CAP_III["Ch. III
Life-Saving
Appliances"] SOLAS_CAP -->|"GMDSS"| CAP_IV["Ch. IV
Radiocommunications
GMDSS mandatory"] SOLAS_CAP -->|"charts, AIS,
VDR, ECDIS"| CAP_V["Ch. V
Safety of
Navigation"] SOLAS_CAP -->|"safety management"| CAP_IX["Ch. IX
ISM Code
SMS mandatory"] SOLAS_CAP -->|"security measures
after 9/11"| CAP_XI["Ch. XI-2
Special maritime
security measures"] CAP_IX -.-|"implements"| ISPS CAP_III -.-|"detailed by"| LSA CAP_V -.-|"requires competence under"| STCW MARPOL ==>|"6 technical
annexes"| ANEXOS_M["MARPOL Annexes"] ANEXOS_M -->|"crude oil and products
SOPEP · Oil record book"| ANX_I["Annex I
Oil
Special areas:
Mediterranean, Baltic..."] ANEXOS_M -->|"noxious liquid chemicals
Categories X,Y,Z,OS"| ANX_II["Annex II
Noxious Liquid
Substances in Bulk"] ANEXOS_M -->|"packaging,
marking, labelling"| ANX_III["Annex III
Harmful Substances
in Packaged Form"] ANEXOS_M -->|"treatment of
sewage"| ANX_IV["Annex IV
Sewage"] ANEXOS_M -->|"integrated garbage
management on board"| ANX_V["Annex V
Garbage
General discharge
prohibition"] ANEXOS_M -->|"SOx, NOx, CO2
ECA · EEDI · CII"| ANX_VI["Annex VI
Air Pollution
0.50% sulfur cap
since 2020"] STCW ==>|"mandatory and
recommended parts"| STCW_COD["STCW Code"] STCW_COD -->|"minimum competence
requirements"| PARTE_A["Part A
Mandatory standards
Competence tables
by function and level"] STCW_COD -->|"implementation
guidance"| PARTE_B["Part B
Recommended guidance
Assessment criteria"] STCW_COD -->|"standardized training
material"| CURSOS_M["IMO Model Courses
1.19 FBSM · 1.20 FSEI
1.21 PSM · 1.29 BP
2.03 ISPS · 7.04 OR"] PARTE_A -->|"defines 7 functions"| FUNCIONES["STCW Functions
1. Navigation
2. Cargo handling
3. Ship control
4. Marine engineering/electrical
5. Maintenance and repair
6. Radiocommunications
7. Security"] MSC ==>|"mandatory technical
codes"| OTROS["Associated Codes"] OTROS -->|"9 classes of
dangerous goods"| IMDG["☢️ IMDG Code
Dangerous Goods
Classification · Packaging
Stowage · Segregation"] OTROS -->|"LNG, LPG
and liquefied gases"| IGC["❄️ IGC Code
Gas Carriers
Tank types
1, 2, 3, membrane"] OTROS -->|"bulk chemical
products"| IBC["🧪 IBC Code
Bulk Chemicals
Product list and
requirements"] OTROS -->|"navigation in the
Arctic and Antarctic"| POLAR["🧊 Polar Code
Polar Waters
In force 2017
Categories A, B, C"] OTROS -->|"specifications for
life-saving equipment"| LSA["🛟 LSA Code
Life-Saving
Appliances"] OTROS -->|"fire detection and
extinguishing"| FSS["🔥 FSS Code
Fire Safety
Systems"] IMDG -.-|"complements"| ANX_III COLREG -.-|"competent navigator
under STCW"| STCW MARPOL -.-|"safe ship under"| SOLAS classDef imo fill:#061525,stroke:#00d4ff,color:#fff,font-size:14px classDef comite fill:#0a1e30,stroke:#357df9,color:#fff classDef convenio fill:#081a2d,stroke:#00d4ff,color:#e8f4f8,font-size:12px classDef codigo fill:#1d1808,stroke:#ffcd35,color:#fff2bf,font-size:11px classDef anexo fill:#08211a,stroke:#00b090,color:#dcfff6,font-size:11px classDef organo fill:#0a1e30,stroke:#7acbff,color:#e8f4f8 classDef mision fill:#08211a,stroke:#00b090,color:#dcfff6,font-size:12px classDef funcion fill:#1b1019,stroke:#fc5185,color:#ffe6ee,font-size:11px class IMO imo class MSC,MEPC,LEG,TC,FAL comite class ASAMBLEA,CONSEJO,SECRETARIA organo class SOLAS,STCW,COLREG,SAR,ISPS,MARPOL,BWM,AFS,CLC,FUND,LLMC convenio class IMDG,IGC,IBC,POLAR,LSA,FSS,CAP_II,CAP_III,CAP_IV,CAP_V,CAP_IX,CAP_XI codigo class ANX_I,ANX_II,ANX_III,ANX_IV,ANX_V,ANX_VI anexo class PARTE_A,PARTE_B,CURSOS_M codigo class SOLAS_CAP,ANEXOS_M,STCW_COD,OTROS convenio class MISION mision class FUNCIONES funcion
International Maritime Organization
Established 1948 · Headquarters: London
175 member states"] IMO -.->|"Mission: safe navigation,
protection of the marine environment,
competent seafarers"| MISION(["🌍 Safe navigation · Clean seas · Competent seafarers"]) IMO ==>|"governs"| ASAMBLEA["📋 Assembly
Supreme body · Meets every 2 years
Approves budget and resolutions"] IMO ==>|"directs"| CONSEJO["🏢 Council
Executive body · 40 members
Supervises between Assembly sessions"] IMO ==>|"administers"| SECRETARIA["📝 Secretariat
Coordinates technical work
~300 international officers"] CONSEJO ==>|"safety"| MSC["⚓ MSC
Maritime Safety
Committee
Main technical committee"] CONSEJO ==>|"environment"| MEPC["🌿 MEPC
Marine Environment
Protection Committee"] CONSEJO ==>|"maritime law"| LEG["⚖️ Legal Committee
Liability and
compensation"] CONSEJO -->|"capacity-building for
developing states"| TC["🎓 Technical
Cooperation Committee"] CONSEJO -->|"simplification of
formalities"| FAL["📄 Facilitation
Committee"] MSC ==>|"most important
maritime safety convention"| SOLAS["🛡️ SOLAS 1974
Safety of Life
at Sea
14 chapters · Mandatory"] MSC ==>|"maritime professional
competence"| STCW["📚 STCW 1978/2010
Training, Certification
and Watchkeeping
Manila Amendments 2010"] MSC ==>|"rules of the road
at sea"| COLREG["🚦 COLREG 1972
International Regulations
for Preventing Collisions
38 Rules + 4 Annexes"] MSC -->|"search and rescue
coordination"| SAR["🆘 SAR 1979
Search and
Rescue
Global SAR plan"] MSC -->|"protection against
unlawful acts"| ISPS["🔒 ISPS Code
Ship and Port Facility
Security
Post-9/11 · Mandatory 2004"] MEPC ==>|"most complete
environmental convention"| MARPOL["🌊 MARPOL 73/78
Prevention of Pollution
from Ships
6 technical annexes"] MEPC -->|"invasive species through
ballast water"| BWM["🦠 BWM 2004
Ballast Water
Management
In force since 2017"] MEPC -->|"toxic antifouling
paints"| AFS["🎨 AFS 2001
Anti-Fouling
Systems
Bans TBT"] LEG -->|"who pays for
oil spill damage?"| CLC["💰 CLC 1969/92
Civil Liability for Oil
Pollution Damage
Strict shipowner liability"] LEG -->|"supplementary fund when
CLC is not enough"| FUND["🏦 FUND 1992
International Compensation
Fund
Financed by oil receivers"] LEG -->|"maximum compensation
limit"| LLMC["📏 LLMC 1976/96
Limitation of
Liability
Based on vessel GT"] SOLAS ==>|"structure"| SOLAS_CAP["14 SOLAS Chapters"] SOLAS_CAP -->|"structure and
stability"| CAP_II["Ch. II-1/II-2
Construction · Subdivision
Stability · Fire protection"] SOLAS_CAP -->|"boats, rafts,
lifejackets"| CAP_III["Ch. III
Life-Saving
Appliances"] SOLAS_CAP -->|"GMDSS"| CAP_IV["Ch. IV
Radiocommunications
GMDSS mandatory"] SOLAS_CAP -->|"charts, AIS,
VDR, ECDIS"| CAP_V["Ch. V
Safety of
Navigation"] SOLAS_CAP -->|"safety management"| CAP_IX["Ch. IX
ISM Code
SMS mandatory"] SOLAS_CAP -->|"security measures
after 9/11"| CAP_XI["Ch. XI-2
Special maritime
security measures"] CAP_IX -.-|"implements"| ISPS CAP_III -.-|"detailed by"| LSA CAP_V -.-|"requires competence under"| STCW MARPOL ==>|"6 technical
annexes"| ANEXOS_M["MARPOL Annexes"] ANEXOS_M -->|"crude oil and products
SOPEP · Oil record book"| ANX_I["Annex I
Oil
Special areas:
Mediterranean, Baltic..."] ANEXOS_M -->|"noxious liquid chemicals
Categories X,Y,Z,OS"| ANX_II["Annex II
Noxious Liquid
Substances in Bulk"] ANEXOS_M -->|"packaging,
marking, labelling"| ANX_III["Annex III
Harmful Substances
in Packaged Form"] ANEXOS_M -->|"treatment of
sewage"| ANX_IV["Annex IV
Sewage"] ANEXOS_M -->|"integrated garbage
management on board"| ANX_V["Annex V
Garbage
General discharge
prohibition"] ANEXOS_M -->|"SOx, NOx, CO2
ECA · EEDI · CII"| ANX_VI["Annex VI
Air Pollution
0.50% sulfur cap
since 2020"] STCW ==>|"mandatory and
recommended parts"| STCW_COD["STCW Code"] STCW_COD -->|"minimum competence
requirements"| PARTE_A["Part A
Mandatory standards
Competence tables
by function and level"] STCW_COD -->|"implementation
guidance"| PARTE_B["Part B
Recommended guidance
Assessment criteria"] STCW_COD -->|"standardized training
material"| CURSOS_M["IMO Model Courses
1.19 FBSM · 1.20 FSEI
1.21 PSM · 1.29 BP
2.03 ISPS · 7.04 OR"] PARTE_A -->|"defines 7 functions"| FUNCIONES["STCW Functions
1. Navigation
2. Cargo handling
3. Ship control
4. Marine engineering/electrical
5. Maintenance and repair
6. Radiocommunications
7. Security"] MSC ==>|"mandatory technical
codes"| OTROS["Associated Codes"] OTROS -->|"9 classes of
dangerous goods"| IMDG["☢️ IMDG Code
Dangerous Goods
Classification · Packaging
Stowage · Segregation"] OTROS -->|"LNG, LPG
and liquefied gases"| IGC["❄️ IGC Code
Gas Carriers
Tank types
1, 2, 3, membrane"] OTROS -->|"bulk chemical
products"| IBC["🧪 IBC Code
Bulk Chemicals
Product list and
requirements"] OTROS -->|"navigation in the
Arctic and Antarctic"| POLAR["🧊 Polar Code
Polar Waters
In force 2017
Categories A, B, C"] OTROS -->|"specifications for
life-saving equipment"| LSA["🛟 LSA Code
Life-Saving
Appliances"] OTROS -->|"fire detection and
extinguishing"| FSS["🔥 FSS Code
Fire Safety
Systems"] IMDG -.-|"complements"| ANX_III COLREG -.-|"competent navigator
under STCW"| STCW MARPOL -.-|"safe ship under"| SOLAS classDef imo fill:#061525,stroke:#00d4ff,color:#fff,font-size:14px classDef comite fill:#0a1e30,stroke:#357df9,color:#fff classDef convenio fill:#081a2d,stroke:#00d4ff,color:#e8f4f8,font-size:12px classDef codigo fill:#1d1808,stroke:#ffcd35,color:#fff2bf,font-size:11px classDef anexo fill:#08211a,stroke:#00b090,color:#dcfff6,font-size:11px classDef organo fill:#0a1e30,stroke:#7acbff,color:#e8f4f8 classDef mision fill:#08211a,stroke:#00b090,color:#dcfff6,font-size:12px classDef funcion fill:#1b1019,stroke:#fc5185,color:#ffe6ee,font-size:11px class IMO imo class MSC,MEPC,LEG,TC,FAL comite class ASAMBLEA,CONSEJO,SECRETARIA organo class SOLAS,STCW,COLREG,SAR,ISPS,MARPOL,BWM,AFS,CLC,FUND,LLMC convenio class IMDG,IGC,IBC,POLAR,LSA,FSS,CAP_II,CAP_III,CAP_IV,CAP_V,CAP_IX,CAP_XI codigo class ANX_I,ANX_II,ANX_III,ANX_IV,ANX_V,ANX_VI anexo class PARTE_A,PARTE_B,CURSOS_M codigo class SOLAS_CAP,ANEXOS_M,STCW_COD,OTROS convenio class MISION mision class FUNCIONES funcion
Key IMO concepts and its main conventions
🏛️ IMO — International Maritime Organization
UN specialized agency responsible for the safety and security of shipping and the prevention of marine pollution from ships.
- Foundation: Convention adopted in 1948, in force since 1958
- Headquarters: London, United Kingdom
- Members: 175 states + 3 associate members
- Guiding principle: “Safe navigation, clean seas, competent seafarers”
- Instruments: Conventions, codes, guidelines, and binding resolutions
- Amendments: Tacit acceptance procedure
🛡️ SOLAS — Safety of Life at Sea
The most important international maritime safety treaty. Its origin dates back to the sinking of the Titanic (1912). Current version: 1974 with the 1988 Protocol and continuing amendments.
- Objective: Minimum standards for construction, equipment, and ship operation
- Scope: Ships on international voyages
- Structure: 14 chapters
- Certificates: Passenger Ship Safety, Construction, Equipment, and Radio
- Control: Port State Control (PSC)
🌊 MARPOL 73/78 — Pollution Prevention
The main convention for preventing pollution of the marine environment caused by ships.
- 6 Annexes: Oil (I), Noxious liquid chemicals (II), Packaged harmful substances (III), Sewage (IV), Garbage (V), Emissions (VI)
- Special areas: Mediterranean, Baltic, North Sea, Caribbean, Red Sea
- ECA: Emission Control Areas with strict SOx and NOx limits
- 2020 milestone: Global sulfur limit reduced to 0.50%
- Decarbonization: IMO strategy to reduce GHG emissions from shipping
📚 STCW — Training, Certification and Watchkeeping
International minimum training standards for seafarers. Legal basis for HydroAbyss training content.
- Origin: 1978, revised in 1995, Manila Amendments 2010
- Code: Part A (mandatory) + Part B (recommended)
- 7 Functions: Navigation, Cargo, Control, Engineering, Maintenance, Radio, Security
- 3 Levels: Support, Operational, Management
- Model Courses: 1.19 FBSM, 1.20 FSEI, 1.21 PSM, 1.29 BP
🚦 COLREG — Collision Prevention Regulations
The “rules of the road at sea”. They regulate navigation conduct, lights, shapes, and sound signals.
- Structure: 38 Rules in 5 Parts + 4 Annexes
- Part B: Steering and sailing rules
- Part C: Lights and shapes
- Part D: Sound and light signals
- Rule 5: Proper lookout — one of the most cited rules in casualty investigations
🆘 SAR — Search and Rescue
International search and rescue plan dividing oceans into SAR regions with MRCC coordination centers.
- Complement: IAMSAR Manual (3 volumes)
- SRR: Regions assigned to each coastal state
- SOLAS: Chapter V requires assistance to persons in distress
🔒 ISPS — Ship and Port Facility Security
Post-9/11 code to protect maritime transport against unlawful acts.
- Implementation: SOLAS Chapter XI-2, mandatory since July 2004
- 3 Levels: Normal (1), Heightened (2), Exceptional (3)
- Roles: PFSO, SSO, CSO
- Plan: Each ship and facility must have an approved plan
☢️ IMDG — Dangerous Goods Code
It regulates the safe carriage of dangerous goods by sea through nine hazard classes.
- 9 Classes: Explosives, gases, flammable liquids, flammable solids, oxidizers, toxics, radioactive, corrosives, miscellaneous
- Content: Classification, packaging, marking, labelling, stowage, and segregation
- Mandatory: Since 2004
- Updates: Every 2 years