Classification or Rating a fire related to use of Fire Extingushers

Most every fire is different; they are classified according to the type of fuel that is burning and can be rated by size 1 through 10.   If you use the wrong type of fire extinguisher  or agent on the wrong class of fire, you can in fact, make matters worse.  This is why understanding Portable Fire Extinguisher and good training is very important to understand the different fire classifications and fire extinguishers to prevent a mistake and  to help you successful extinguish a fire safely.

The Classification of a fire, and the rating of portable fire extinguisher in the United States America shows the size,a Class A, B, C, D, and K fire extingusher unit can be expected to put out on what type and size of fire.  These rating  are controlled by  laboratory testing (by Underwriters' Laboratories and/or Your Local Fire Marshall, UL or FM) determines classification before a manufacturer puts a model on the market.  The higher the fire extinguisher rating or classification, the greater the extinguishing capacity.  For example, a unit classified 4A can be expected to extinguish twice as much class A fire as one classified 2A. When comparing units of similar physical size, compare classifications to be sure which unit will provide the greatest fire fighting potential.  

Extinguisher international classification chart above..

NFPA Classification of Hazards for Portable Fire Extinguishers

Extra (High) Hazard. Extra hazard occupancies are locations where the total amount of Class A combustibles and Class B flammables present, in storage, production, use, finished product, or combination thereof, is over and above those expected in occupancies classed as ordinary (moderate) hazard. These occupancies could consist of woodworking, vehicle repair, aircraft and boat servicing, cooking areas, individual product display showrooms, product convention center displays, and storage and manufacturing processes such as painting, dipping, and coating, including flammable liquid handling. Also included is warehousing of or in-process storage of other than Class I and Class II commodities as defined by NFPA 13, Standard for the Installation of Sprinkler Systems. Light (Low) Hazard. Light hazard occupancies are locations where the total amount of Class A combustible materials, including furnishings, decorations, and contents, is of minor quantity. This can include some buildings or rooms occupied as offices, classrooms, churches, assembly halls, guest room areas of hotels/motels, and so forth. 

Who is the NFPA?  (National Fire Protection Association) is highly involved help in developing a set standards for firefighting in the United States other countries  through out the world.  This includes the classification of Fires and use of portable fire extinguishers portable fire extinguishers. 

The National Fire Protection Association, NFPA, a private non-profit organization, is the leading authoritative source of technical background, data, and consumer advice on fire protection, problems and prevention. Their web site is  http://www.nfpa.org/.

The primary goal of NFPA is to reduce the worldwide burden of fire and other hazards on the quality of life by providing and advocating scientifically-based consensus codes and standards, research, training, and education.

What does UL (Underwriters Lavatories) do?  UL is the trusted source across the globe for product compliance such as Portable Fire Extinguishers.   Benefiting a range of customers - from manufacturers and retailers to consumers and regulating bodies - they have tested multitudes of products for public safety and consistency.  Their web site is

UL can offer one of the conformity assessment industry’s broadest portfolios of capabilities and certification marks. Their unique mix of local expertise in global markets and deep industry knowledge helps bring safer consistent products to markets for the public, encluding fire extinguisher classifications.  Web site is  http://www.ul.com.

 What does FM Global (Factory Mutual Insurance Company) do?   FM Approvals: Setting the Standard in Third-Party Certification of equipment.  Customers demand quality, and a manufacture position in the marketplace depends on producing quality products.  Ensure the quality of your products and protect your market share by obtaining third-party certification from FM Approvals. Industrial and commercial companies around the world rely on products and services that are FM Approved and specification tested to standards manufacture set and NFPA recommends. . The FM APPROVED mark, which is backed by scientific research and testing, tells customers your product conforms to the highest standards such as on a Portable Fire Extinguisher.   Their Web site is http://www.fmglobal.com/

 Types of Fire Classifications

Fire Classifications for Portable Fire Extinguishers

Types of Fuels that Classifies Fires

International Fire Extinguisher Classification Symbols

Class A

ORDINARY COMBUSTIBLES:
Solid combustible materials that are not metals. (Class A fires generally leave an Ash.) wood, paper, cloth, trash, plastics and other ordinary materials

CLASS B

FLAMMABLE LIQUIDS & GASES: such as: gasoline, oils, paint lacquer and tar.  Any non-metal in a liquid state, on fire, this classification also includes flammable gases.   (Class B fires generally involve materials that  Boil or Bubble.)

CLASS C

FIRES INVOLVING LIVE ELECTRICAL EQUIPMENT  As long as it's "plugged in," it would be considered a class C fire.  (Class C fires generally deal with electrical Current.)

CLASS D

COMBUSTIBLE METALS OR METAL ALLOYS such as: potassium, sodium, titanium, magnesium.  Unless you work in a laboratory or in an industry that uses these materials, it is unlikely you'll have to deal with a Class D fire. It takes special extinguishing agents (Metal-X, foam) to fight such a fire.