How to Prevent Fires on Ships: A Maritime Safety Guide

Fire prevention on a commercial vessel is a regulatory obligation, not a recommendation. SOLAS Chapter II-2 dedicates three regulations (4, 5, and 6) specifically to preventing fire before it starts, and port state control inspectors treat prevention deficiencies, from fuel leaks left unattended to expired firefighting equipment, as seriously as they treat structural failures. For fleet managers and safety officers, fire prevention is the area where compliance effort delivers the most return, because a fire that never starts costs nothing to suppress.

What SOLAS Requires for Fire Prevention

SOLAS Chapter II-2 organizes its fire safety regulations around a scenario-based sequence: prevent ignition first, then detect, suppress, contain, and escape. Prevention sits at the front of that chain, in Part B of the chapter, and covers three specific regulations.

Regulation 4, "Probability of ignition," requires means to control leaks of flammable liquids, limit the accumulation of flammable vapors, restrict ignition sources near fuel-handling areas, and separate high-fire-risk spaces from the rest of the vessel through ventilation and structural measures. Regulation 5, "Fire growth potential," addresses the restricted use of combustible materials in construction and outfitting, including surface-finish and insulation standards that limit how fast a fire can spread once started. Regulation 6, "Smoke generation potential and toxicity," reduces the hazard from smoke and toxic products in spaces where crew or passengers live and work.

Together, these three regulations form the prevention layer that every vessel's Safety Management System (SMS) must implement. The FSS Code, 2026 Edition and the Fire Test Procedures (FTP) Code then provide the engineering and testing standards that prove compliance.

The Five Operational Causes of Shipboard Fires

Prevention regulations are only as effective as the daily practices that support them. Across flag state casualty reports and P&I Club loss data, the same five operational causes appear repeatedly.

Fuel and Oil System Leaks

Leaking fuel lines, purifier overflows, and cracked flexible hoses put flammable liquid in contact with hot surfaces. Machinery space fires account for a disproportionate share of shipboard fire incidents, and fuel-on-hot-surface ignition is the primary mechanism. Prevention means regular inspection of fuel and lubricating oil piping, replacement of deteriorated flexible connections on schedule, and prompt repair of any observed seepage. SOLAS II-2 Regulation 4 requires means to control such leaks.

Electrical Faults

Overloaded circuits, loose terminal connections, damaged cable insulation, and non-marine-rated equipment introduce arcing or resistive heating into spaces filled with combustible materials. Prevention includes thermographic surveys of switchboards and distribution panels, torque-checking of terminal connections, and enforcing that only marine-type-approved equipment is installed aboard. Electrical maintenance logs should record inspection dates and findings.

Hot Work Without Proper Controls

Welding, burning, and grinding outside designated hot-work spaces are a leading cause of fire during maintenance periods, both at sea and during port stays and dry-dock. A formal hot-work permit system, with fire watches, atmosphere testing in adjacent spaces, and verification that combustible materials are removed or shielded, is required under the vessel's ISM Code procedures and reinforced by SOLAS II-2 Regulation 4.

Galley and Accommodation Hazards

Deep fryers, cooking ranges, and laundry driers generate heat in spaces surrounded by combustible finishes and ventilation ducting. Prevention includes regular cleaning of grease traps and exhaust ducting, functional testing of galley suppression systems, and enforcing no-smoking rules outside designated areas. SOLAS II-2 Regulation 5 limits combustible material in accommodation construction specifically to contain fires originating in these spaces.

Cargo-Related Ignition

Certain cargoes generate heat through oxidation, chemical reaction, or friction. Containers loaded with undeclared or mis-declared dangerous goods add an invisible risk. Prevention for cargo-related ignition relies on proper cargo documentation review against the IMDG Code, stowage planning per the vessel's Document of Compliance, atmosphere monitoring in cargo holds, and functioning ventilation systems.

Fire Drills and Crew Readiness

Prevention extends beyond hardware to crew competence. SOLAS Chapter III, Regulation 19.3.2 requires every crew member to participate in at least one fire drill every month. If more than 25% of the crew have not participated in the previous month, a drill must take place within 24 hours of leaving port. SOLAS Chapter II-2, Regulation 15 adds that on-board training in the use of fire-extinguishing systems and appliances must be planned and recorded.

Effective drill practice means simulating realistic scenarios (machinery space fire, accommodation fire, galley fire) rather than repeating the same script. The crew should demonstrate correct use of fire safety equipment including SCBA, fire hoses, portable extinguishers, and fixed-system release procedures. Drill records are checked during both ISM audits and port state control inspections, and gaps in the record are a detainable deficiency.

The Fire and Safety Plan

Every SOLAS vessel must carry a fire and safety plan that shows the location of every fire detection panel, suppression system, extinguisher, fire main, hydrant, SCBA storage point, and means of escape. The plan uses IMO fire control symbols in accordance with IMO Resolution A.952(23) and ISO 17631 for vessels constructed after January 2004, or Resolution A.654(16) for earlier vessels. A copy must be permanently displayed in a prominent location, and a duplicate kept in a weathertight enclosure outside the deckhouse for shore-based fire parties.

Keeping the plan current after any equipment change, accommodation refit, or system upgrade is a regulatory requirement that is easy to overlook and frequently cited during surveys. ANS supplies the IMO fire control symbol sets and safety signs needed to update the plan and the corresponding on-board signage.

Prevention Starts Before the Voyage

A vessel that departs with leaking fuel lines, expired extinguishers, untested detection panels, or a crew that has not drilled in weeks is not compliant with SOLAS and is not safe. Fire prevention is not one regulation or one piece of equipment; it is the combined effect of design, maintenance, training, and operational discipline.For vessel operators, safety officers, auditors, and maritime training organizations, the Fire Safety Systems (FSS) Code 2026 Edition provides the current IMO requirements supporting fire prevention, detection, and suppression under SOLAS Chapter II-2. Keeping the latest edition onboard helps support regulatory compliance and inspection readiness.

Frequently Asked Questions

Q. What SOLAS regulations cover fire prevention on ships?

SOLAS Chapter II-2, Regulations 4, 5, and 6 address fire prevention specifically. Regulation 4 covers probability of ignition, Regulation 5 covers fire growth potential, and Regulation 6 covers smoke generation and toxicity. Together, they form Part B of the chapter.

Q. How often are fire drills required on ships?

SOLAS Chapter III, Regulation 19.3.2 requires every crew member to participate in at least one fire drill every month. If more than 25% of the crew have not drilled in the previous month aboard that vessel, a drill must take place within 24 hours of leaving port.

Q. What is the most common cause of fire on ships?

Fuel and lubricating oil leaks onto hot engine-room surfaces are consistently reported as the leading cause of machinery space fires aboard commercial vessels. Electrical faults and uncontrolled hot work are the next most common causes.

Q. What should the fire and safety plan include?

The plan must show the location of every fire detection panel, fixed suppression system, portable extinguisher, fire main, hydrant, SCBA point, and means of escape, using IMO fire control symbols per Resolution A.952(23) or A.654(16). A copy must be displayed prominently and a duplicate stored outside the deckhouse.

Q. What is a hot-work permit and why does it matter?

A hot-work permit is a formal authorization to perform welding, burning, or grinding outside designated hot-work spaces. The permit system requires fire watches, atmosphere testing, and removal of combustibles before work begins, and is required under the vessel's ISM Code safety management procedures.

Q. Does fire prevention affect port state control inspections?

Yes. Port state control officers check fire prevention measures including fuel-system condition, extinguisher service dates, detection panel functionality, fire drill records, and the accuracy of the fire and safety plan. Deficiencies in any of these areas can result in detention.