Fire Extinguisher Servicing FAQ’s

Fire Extinguisher Servicing FAQ’s

We’ve put together a collection of Frequently Asked Questions FAQs about Fire Extinguishers and Fire Extinguisher Servicing. If you have a question or need further assistance with your fire extinguishers or any of our other services, please Contact Us.

What are the various classes of fire

• Class A – fires involving solid materials such as wood, paper or textiles
• Class B – fires involving flammable liquids such as petrol, diesel or oils
• Class C – fires involving gases
• Class D – fires involving metals such as potassium or magnesium
• Class E – fires involving live electrical apparatus*
• Class F – fires involving cooking oils such as in deep-fat fryers

* Technically ‘Class E’ doesn’t exist. Once you have turned off the electricity the fire becomes the same as any other. Before this classification system, there was a classification of electrical fires, but since electricity itself is a cause of fire, these types of fires have been incorporated into the main classes.

Why are there so many types of Fire Extinguisher?

As can be seen by the previous answer there are many types of fire extinguisher because there are many different types of fire. Each extinguisher is designed to be used on a specific class of fire. It is important to use the right extinguisher to ensure that your actions are as effective as possible and don’t further ignite the fire.

What are the different colour codes on fire extinguishers?

• Fire extinguishers have colour codes labelling the type of extinguisher they are. These are represented on a band at the top of the extinguisher.
• Their purpose is to make identification easier and faster for the user.
• Each extinguishing medium is assigned its own colour code:
  • Red for water,
  • Cream for foam,
  • Blue for dry power,
  • Black for carbon dioxide.
  • Yellow, is added for the new Wet Chemical type of fire extinguisher.

What chemicals are used in a fire extinguisher?

As you would probably expect different chemicals are used for each different type of fire.

• Dry chemical extinguishers use a powder-based agent which prevents chemical reactions involving heat, oxygen and fuel, this extinguishes the fire. The substances used for this are Monoammonium phosphate, sodium bicarbonate, potassium bicarbonate, potassium chloride and sodium bicarbonate based dry chemical (Foam compatible).
• Foam extinguishers use an aqueous film forming foam, alcohol-resistant foams, film-forming fluoroprotein and a compressed air foam system. These smother the fires and prevent oxygen from fuelling it.
• Water extinguishers use water to cool the burning material. This can be pump type water, air pressurized water and water mist
• Wet chemical and water additives extinguish a fire by forming a soapy foam blanket over burning oil and cooling the oil down below its ignition temperature. They use wetting agents, antifreeze and loaded stream (an alkali metal salt solution which when added to water lowers its freezing point).
• Carbon Dioxide extinguishers put out fires by displacing oxygen and removing heat from the combustion zone. They use halocarbon replacements, CO2, novec 1230, potassium aerosol and E-36 cryotec.
• WATERMIST – there are no chemicals in the water mist extinguisher, however guess what it does contain water. What makes water mist different or standard water extinguishers is the nozzle on the extinguisher disperses ‘dry’ water mist particles at a microscopic scale (ranging from 50 to 300µm, 50µm (micrometres) is 5/100ths of 1millimeter).

What type of fire can each Fire Extinguisher be used on?

• Dry chemical extinguishers can be used on all fire except oil fires (class F fires)
• Foam extinguishers are best used on combustible materials (class A) and flammable solids and liquids (class B)
• Water extinguishers can only be used on combustible materials such as wood, paper, cloth, trash, and plastics (class A)
• Wet chemical extinguishers can be used on combustible materials (class A) and oil fires (class F). These extinguishers have been specifically developed to tackle fires involving cooking oils and fats and contain potassium salts which both cool the flames and smother the fire’s oxygen content.
• CO2 extinguishers can be used on flammable liquids (class B) and electrical fires.
• Fire extinguishers with a Class C rating are suitable for fires in “live” electrical equipment. Both monoammonium phosphate and sodium bicarbonate are commonly used to fight this type of fire because of their nonconductive properties.

Are any Fire Extinguishers all purpose?

NO

Currently there aren’t any all-purpose fire extinguishers. However, dry chemical extinguishers can be used on the majority of fires with a few exceptions.

What happens if you use the wrong fire extinguisher?

Be Aware – Using the wrong extinguisher could worsen the situation. For example putting water on an oil/electric fire would cause the fire to get bigger.

Make sure you use the correct one as its safer

Can you repair a fire extinguisher?

NO – a fire extinguisher should only ever be serviced or repaired by a professional

How often should fire extinguishers be serviced?

Fire extinguishers must be serviced every 12 months or after each use by a BAFE SP101 certified service provider.

IMPORTANT : If an extinguisher is found to be leaking, it should be serviced immediately.

How do you dispose of a fire extinguisher that is no longer serviceable?

Fire extinguishers should be collected and disposed of in an environmentally sound way by your appointed Service Provider. A waste transfer note should be issued by your Service Provider to evidence that the extinguisher has been disposed of in accordance with regulations.

Is there a simple guide to Fire Extinguishers and there use?

Water Fire Extinguisher – the most common extinguisher that covers freely burning materials such as: Paper, Fabrics, Wood.
Water extinguishers are not safe on electrical risks or flammable liquids such as cooking oils, petroleum, and petroleum products.

Powder Fire Extinguisher – a multi-purpose extinguisher that covers the following types of fire:

• Freely burning materials such as paper, wood, curtains, etc.
• Flammable liquids such as petrol, diesel, white spirits, etc.
• Flammable gases such as Butane, Propane, etc.
• Electrical Risk fires

Not Suitable For use on cooking oil fires or indoor use.

Foam Fire Extinguisher – a dual purpose extinguisher that covers freely burning materials such as the water extinguisher does. It also provides cover for the following flammable liquids: Petrol, Diesel &
White Spirits

Not suitable for use on cooking oil.

CO2 Fire Extinguisher – predominantly used for electrical risk fires.

Wet Chemical Fire Extinguisher – designed for Cooking Oil fires only.

Fire Blanket – used to smother smaller fires, cutting off the oxygen supply. Typically used to cover fires on toasters, kettles, small electric domestic appliances, microwaves

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