Classification of fire; types and sources of ignition
Governing: STCW Table A-VI/1-2; UK classification (BS EN 2). Builds on: L1.1.
Classes of fire
The UK classification groups fires by fuel. The class tells you which extinguishing agents are safe and effective.
| Class | Fuel | Yacht examples |
|---|---|---|
| A | Solids, usually organic: wood, paper, fabric, plastics | Furnishings, linen, teak, rope, cardboard in stores |
| B | Flammable liquids | Diesel, petrol, lube oil, paint, solvents, alcohol |
| C | Flammable gases | LPG for barbecues and galley, acetylene |
| D | Metals | Magnesium, aluminium swarf, some battery materials |
| F | Cooking oils and fats | Galley fryers, woks, pans |
| Electrical (symbol, not a letter) | Live electrical equipment | Switchboards, AV racks, chargers, dryers |
Electrical equipment is not itself a fuel; the danger is the live current. Isolate it and the fire becomes whatever class of material is burning.
Lithium-ion battery fires do not fit neatly into any class; they are covered in L4.3.
Types of ignition
Table A-VI/1-2 asks you to know types and sources of ignition. The usual groupings:
| Type | Mechanism | Examples |
|---|---|---|
| Chemical | Reactions that release heat | Oily rags oxidising, reactive cleaning chemicals mixed, battery thermal runaway |
| Biological | Organic decay generating heat | Damp stored organic material |
| Physical: thermal | Hot surfaces and flames | Exhaust manifolds, galley ranges, irons, heaters |
| Physical: friction | Moving parts | Overheating bearings, slipping belts |
| Physical: electrical | Arcs, sparks, overheating | Loose connections, overloaded sockets, damaged cables |
| Physical: sparks | Hot work, grinding | Welding and cutting during refit |
Where fires start on a yacht
- Galley: unattended pans, fat build-up in hoods and ducts, fryers.
- Laundry: lint in dryers and ducting; the classic crew-area fire.
- Electrical: overloaded extension leads in crew cabins, AV and IT racks, shore power connections.
- Engine room: fuel or oil spray onto hot surfaces, oily bilges, insulation soaked in oil.
- Garage: petrol tenders and jet skis, and increasingly lithium-ion toys on charge.
- Refit and hot work: sparks falling through openings, fires found hours later.
- Smoking: discarded cigarettes on deck cushions or in bins.
- Guest areas: candles, heaters, hair dryers, phone chargers left on bedding.
CAUTION — Spontaneous combustion Rags soaked in oil, varnish or teak oil can self-heat and ignite hours later. Keep them in a closed metal bin, spread out to dry outdoors, or dispose of them ashore.
Flammable materials and spread
Yachts are full of fire load: fabrics, foam, veneers and plastics in guest areas. The REG Yacht Code restricts materials and requires fire-resisting divisions, but those only work if doors are kept closed and penetrations sealed.
TIP — Look like an inspector On rounds, ask of each space: what could ignite here, what would it ignite, and how would it spread? That habit is the whole of prevention.