Minimizing fire risks is something that business owners, homeowners and facility managers in New Zealand must be prepared for.

One of the key fire suppression tools available is the Fire Extinguisher. Of course, you need both the right type of extinguisher on hand and an extinguisher that receives regular maintenance. That starts with understanding the six main fire classes and the six types of available extinguishers to address each type of fire. The right extinguishers ensure that you protect lives and, in the case of businesses and facilities, protect assets and remain within the legal regulations.

Fire Classes

There are six fire classes. Each class is defined by the type of fuel in the fire. This approach lets you make better decisions about the kind of extinguisher you need based on the class of fire most likely in your location.

Class A: Paper, Wood, and Plastic

Class A fires are the most common class of fire because of the widespread use of paper, wood, and plastic. These fires can affect anything from rubbish to structures and even clothing. With the exception of carbon dioxide extinguishers and BE powder extinguishers, any fire extinguisher should work against this class.

Class B: Flammable and Combustible Liquids

Class B fires can involve a range of liquids. Common fuel sources include:

• Petrol
  • Kerosene
  • Paint
  • Wax
  • Oil
  • Alcohol
  • Cleaning supplies

Dry powder extinguishers work best against this fire class, along with foam and carbon dioxide suppressors. Do not use water extinguishers against this class of fire.

Class C: Flammable Gases

Class C fires start from a number of commonly used gases found in businesses and homes. Common sources include:

• Propane
  • Butane
  • Liquified petroleum gas
  • Liquified natural gas
  • Acetylene

Dry powder extinguishers are the only acceptable extinguisher type for this class of fire. Make sure you shut down the supply of gas prior to using the extinguisher.

Class D: Combustible Metals

Class D fires remain fairly uncommon and typically occur in industrial settings where high heat and the right kinds of metals appear together. Combustible metals include:

• Titanium
  • Magnesium
  • Aluminium
  • Sodium
  • Lithium
  • Plutonium
  • Calcium
  • Potassium

Class D fires require a special, Class D dry powder extinguisher.

Class E: Electrical

Class E fires can occur anywhere you find electricity but are typically caused by malfunctioning appliances or computer equipment. Vaporizing liquid extinguishers are designed to address this class of fire. 

Dry Powder extinguishers will also work on this type of fire but the powder will have a reaction with the electrical components meaning they will probably need to be replaced.

Class F: Cooking Oils and Fats

Class F fires occur most often in residential, restaurant, or facility kitchens. Common fuel sources include:

• Vegetable oil
  • Olive oil
  • Lard
  • Butter
  • Drippings

Wet chemical extinguishers are the best option for this class of fire. Never use water on Class F fires as it can make the fire worse.

We recommend a Fire Blanket is also installed near this type of hazard.

Types of Fire Extinguishers

While fire extinguishers cannot help you against a large fire, they can help you put out small fires. This limits the potential damage to equipment and the structure, as well as helps prevent injury. You must use the appropriate extinguisher, or you risk making the fire more destructive, rather than less destructive.

There are six commonly available types of fire extinguishers available in New Zealand. You can identify each type by a coloured band on the extinguisher.

Helpful table from FENZ.   https://www.fireandemergency.nz/assets/Documents/Business-and-Landlords/Protecting-your-business-or-Property/Fire-Extinguisher-Position.pdf

How To Identify Fire Extinguisher Types

• Red Coloured Band – Extinguishers with a red band use water as the suppressant. Only use these extinguishers for Class A fires.

• Blue Coloured Band – Extinguishers with a blue band use foam as the suppressant. Only use foam extinguishers for Class A or Class B fires.

• Black Coloured Band – Extinguishers with a black band use carbon dioxide as the suppressant. Only use carbon dioxide extinguishers for Class E fires.

• White Coloured Band – Extinguishers with a white band use dry powder as the suppressant. Only use dry powder extinguishers on Class A, Class B, (some Class C) and Class E fires.

• Oatmeal Coloured Band – Extinguishers with an oatmeal-coloured band use wet chemicals as the suppressant. Only use wet chemical extinguishers on Class A and Class F fires.

Please note that some extinguisher types are considered to have a limited effectiveness on some types of small fires in other fire classes. Check with the ratings on each extinguisher to confirm their suitability for each fire class.

Fire Extinguisher Ratings

Fire Extinguishers come with different ratings to tell you what type and size fire they are rated for. You will find the ratings on the side of each extinguisher but it is also listed below the description of the extinguishers in the shop area of this website.

For example if you have a 2.5kg Dry Powder ABE Extinguisher the rating is 4A:40B:E, This means that this extinguisher has a rating of 4 for an A class fire, 40 for a B class fire and can fight E class fires safely.

Most extinguisher types have multiple different ratings, are suitable for different fire hazard class, types and sizes so need to be carefully considered before purchase and installation.

Think about what your likely fire hazards are and check that the extinguisher type you have will cover those classes of fire.

If you need any help or advice feel free to ask.

We offer a full line of fire extinguishers for your needs.

We can also arrange for a technician to do a Fire Extinguisher inspection and certification (in the Auckland area) For more information, please contact us today.

thefireextinguisherwarehouse@gmail.com