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Fire Extinguisher Ratings - Learn About Fire Classifications and Fire Extinguisher Ratings

Fire extinguisher ratings are designed to indicate the kind of fires they ought to be employed on, and to provide an indication of how powerful they'll be. Each and every fire extinguisher rating in expressed as a series of numbers and letters which indicate the classes of fire they are able to be made use of around the size of fire they are suitable for.


Diverse types of fires are classified by distinct letters, and fire extinguishers ratings may possibly show various letters since they're able to be utilized on more than one particular type of fire. With regards to the size of fires the extinguisher could be employed on, the number gives an indication of this, and generally speaking, the bigger the number, the bigger the fire that the appliance can take care of.


The numerical a part of the fire extinguisher ratings relate straight to tests carried out to measure their effectiveness. A wooden crib test is 1 test that may be used to measure how substantial a fire an appliance can handle. A rating of 13A, as an example, indicates that the extinguisher was in a position to put out 1.3m in the fire. The number on a fire extinguisher rating is as a result an extremely accurate indication of what each and every extinguisher can cope with.

As yet another instance of the numerical rating, the test for measuring the effectiveness of extinguishers for use on flammable liquids refers to the approximate location of fire in square feet that it can be in a position to extinguish. The specific tests differ together with the different fire kinds, but the basic method of accurately measuring the extinguisher's effectiveness may be the identical.


It would appear obvious to believe that the quantity on a fire extinguisher would boost together with the size of it. This can be commonly correct, but size just isn't the only element that effects the quantity within the fire extinguisher rating. With water extinguishers, additives are often mixed together with the water to raise their effectiveness, as a result you might have two appliances that are exactly the same size, but which have distinct numerical ratings, simply because a single is more efficient than the other.


Fire Classifications - The UK and US Differences


As already pointed out, the letters employed in fire extinguisher ratings refer to the classes of fire that they could be safely made use of on. We therefore have to have to look at these fire classifications very first, just before taking a look at the actual ratings for the many types of appliance.


The classifications for the UK and US are comparable, but you'll find some variations, so I will show both. Europe and Australasia also use the exact same classification technique as the UK. The following would be the most important classifications of fires, with US classes shown in brackets:


Class A (also Class A in US)


Any fire involving solid supplies such as wood, card, paper, fabric, etc.


Class B (also Class B in US)


Class B fires involve flammable liquids including kerosene, oils, petrol, paints, diesel, and so on.


Class C (comes under Class B in US)

A separate classification except in US, this category is for flammable gases, which includes butane, methane, etc.


Class D (also Class D in US)


The D Classification is for combustible metals or alloys, for example potassium, magnesium or titanium.


Electrical (Class C in US)


Electrical fires are sometimes referred to as Class E inside the UK, but that is an error as there's no separate classification for electrical fires inside the UK.


Class F (Class K in US)


Particularly relates to fires involving deep fat fryers (fats and oils).

Fire Extinguisher Ratings:


The following information shows the classes of fires covered by the various ypes of appliance:


Primary fire extinguisher ratings shown refer to UK, with US ratings in brackets.


Water Extinguishers:


Classes of fire: A (class A in US)


Carbon Dioxide Extinguishers:


Classes of fire: Electrical, A, B and C (A, B and C in US)

Dry Powder Extinguishers:


Classes of fire: A, B, C and Electrical (A, B and C in US)

Wet Chemical Extinguishers:


Classes of fire: A, F


Foam Extinguishers:


Classes of fire: A and B (A and B in US)


Fire Extinguisher Ratings - Conclusions


Understanding fire classes and extinguisher ratings is vital so that you can be certain of applying the appropriate kind of appliance on any fire inside your workplace. It might be incredibly risky to make use of the wrong type of appliance on some fires, one of the most obvious examples being the usage of water on an electrical fire. Because of this right staff coaching is important for any employees who're needed to use fire fighting equipment.


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