A fire requires a combination of oxygen, fuel and heat. This is commonly called the fire or combustion triangle and is a simple model for understanding the three elements required to start a fire To put a fire out, it must be deprived of one or more of these three elements, but using the wrong extinguisher can make the situation worse.
A fires involving solids such as paper, wood, or textiles
B fires involving liquids such as oil, diesel and petrol
C fires involving gases
D fires involving metals
F fires involving cooking oil and fat
Fires involving live electrical equipment are not included in this list because once the electrical source has been isolated the combustible material fuelling the fire falls into one of the categories above. However, you may see these referred to as Class E fires elsewhere.
Different media are used to fight different types of fire. The most common are water, dry powder, foam and Carbon Dioxide (CO2). Table 1 (below) provided information on which type of extinguisher should be used on each class of fire.
When first sold or put into use, vessels built for the UK market in compliance with the UK Recreational Craft Regulations 2017 (RCR2017) and for the EU market in compliance with Directive 2013/53/EU (the Recreational Craft Directive - RCD), must ensure they do not endanger the health and safety of persons, property or the environment. That includes protection from risk and spread of fire and the provision of fire-fighting equipment appropriate to the fire hazard.
Both the UK and the EU recognise that conformity with the fire protection requirements can be achieved by applying ISO 9094, Small craft - Fire Protection which specifies, among other things, the minimum requirements for firefighting equipment. However, further means of firefighting may be necessary (or required by law). This applies particularly to UK registered private pleasure vessels over 13.7m, which fall under UK Merchant Shipping Regulations, those that are required to comply with the UK Boat Safety Scheme certificate and those that are used for commercial purposes such as training and charter.
On board, it’s good practice to stow fire extinguishers at the exits from each area of the accommodation spaces – by the door of each cabin and by the companionway – so you can fight the fire and keep escape routes clear.
In an ideal world there would not be any flammable liquids on a vessel. But the reality is that most boats will carry spare diesel for the main engine, petrol for an outboard motor and perhaps chemicals for general maintenance. It’s important that these are stowed in areas that are well ventilated. Petrol and other fuels should be kept in a dedicated locker that vents and drains outboard.
It should be possible to tackle an engine room blaze without allowing air to enter the space, as this could make the fire worse. A small hole through which a fire extinguisher can be aimed is one solution, but many owners choose to fit a dedicated automatic extinguisher in the engine bay. The fire rating required will depend on the space in question and advice should be sought from the manufacturer. For larger spaces there are specialist fire systems available, often using inert gases as the fire-extinguishing media.
Table 1 – The Different types of fire extinguisher:
|Media||Advantages||Disadvantages||Suitable for fire groups|
Good cooling properties
|Should never be used on liquid, gas or electrical fires||Type A only|
Leaves a residue
Effectiveness can be reduced by wind
Can cause breathing difficulties
|This is dependent on the type of powder with options of D only, B&C or A B C which is commonly found onboard boats|
Good cooling properties
Can create a heat barrier
Not suitable for electrical fires
|A and sometimes B - suitability varies between different manufacturers|
Does not cause damage or leave a residue
Can be used on live electrical fires
Can cause cold injuries if used incorrectly
Can cause an asphyxiant atmosphere if used in a confined space
Disperses rapidly in open spaces
|Most effective for small class B fires|
Table 2 - Extinguisher recommendations by boat size:
|Approximate length of vessel||Number of fire extinguishers (consider one for each sleeping cabin)||Combined fire rating|
7 - 11m
11 - 13.7m
First published in the RYA Magazine, Summer 2020. Revised 05/2021