Fixed installations
Governing: STCW Table A-VI/1-2 ("instruction in fixed installations"); REG Yacht Code Part A, 15A.7 and Table 15A.1; MGN 681 (M) Amendment 1, section 8. Builds on: L3.1.
Portable extinguishers deal with small fires. Spaces where a fire would grow too fast or burn too hot to fight by hand are protected by fixed systems. As a basic training candidate you will not design or maintain them, but you must know what they are, where they are, and what happens when they operate.
Where fixed systems are required
REG Yacht Code Table 15A.1 requires, for every Category A machinery space, a fixed fire-extinguishing system approved under the Fire Safety Systems (FSS) Code. A machinery space with an oil-fired boiler or oil fuel unit needs one too (15A.7). Larger yachts, Chapter 14.1 garages and battery stowage have further requirements.
Types
| System | How it works | Typical yacht use | Key hazard |
|---|---|---|---|
| CO2 total flooding | Floods the space, reducing oxygen | Engine rooms, older yachts | Lethal to anyone inside |
| Clean agents (chemical gases) | Chemical and physical action on the flame | Engine rooms, technical spaces | Decomposition products; oxygen reduction varies |
| Water mist | Very fine droplets absorb heat and displace oxygen locally | Engine rooms, garages, accommodation | Electrical equipment exposure |
| Sprinklers | Heat-activated heads spray water | Accommodation on larger yachts | Water damage |
| Galley hood systems | Wet chemical discharged into the hood and duct | Galley ranges and fryers | Must be manually activated if detection fails |
| Local application | Water mist or gas aimed at a specific hazard | Generators, purifiers | – |
Older yachts may still have systems using agents now phased out; the SMS will say.
Releasing a gas system
Release is a command decision. The usual sequence:
- Evacuate the space and complete a head count.
- Stop ventilation and close fire dampers.
- Stop fuel: quick-closing valves, fuel pumps.
- Close all doors, hatches and skylights.
- Release from the protected release station, following the posted instructions.
- Keep boundaries cool and monitor temperatures.
- Wait. Opening the space too soon re-admits air and can re-ignite the fire.
Pre-discharge alarms sound in the space before a gas system releases. If you hear one, get out immediately.
WARNING — Never re-enter without authority After a gas release the atmosphere may be lethal. Re-entry is ordered by the master, made with breathing apparatus, after ventilation and testing. MGN 681 requires portable atmosphere testing instruments aboard.
Water mist
Water mist is increasingly common on yachts. It cools strongly, uses little water, and is generally safer for people than gas flooding. MGN 681 notes that water-mist systems have been shown to be the most effective solution for battery-fire suppression and recommends automatic water-based systems in battery compartments.
Your role
- Know which spaces on your yacht have fixed systems and where the release stations are.
- Know the pre-discharge alarm.
- Never obstruct nozzles, detectors or release points with stowed gear.
- Report any accidental damage to pipework or heads.
CAUTION — Accidental release Refit work near CO2 cylinders or release cables has caused accidental discharges. Treat release stations as off limits unless you are trained and ordered.