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Here are some typical extinguishers and their uses: Water extinguishers not pictured and not found in laboratories are suitable for class A paper, wood etc. In these cases, the flames will be spread or the hazard made greater! Water mist extinguishers are suitable for class A and C; see below. Water extinguishers are effective on pool chemicals provided that they are correctly stored away from electrical hazards and equipment; see the blue box below for more on pool chemicals. Dry chemical extinguishers are useful for either class ABC or class BC fires check the label and are your best all around choice for common fire situations.
They have an advantage over CO2 and "clean agent" extinguishers in that they leave a blanket of non-flammable material on the extinguished material which reduces the likelihood of reignition. They also make a terrible mess - but if the choice is a fire or a mess, take the mess!
Note that there are two kinds of dry chemical extinguishers: Type BC fire extinguishers contain sodium or potassium bicarbonate. Type ABC fire extinguishers contain ammonium phosphate. When to use or not use Dry Chemical Extinguishers? Dry chemical extinguishers can be quite corrosive to metals such as aluminum and are also potentially abrasive. ABC extinguishers are much more corrosive than BC extinguishers because the ammonium phosphate agent can undergo hydrolysis to form phosphoric acid and because the molten agent flows into minute cracks.
For this reason, dry chemical ABC extinguishers are not recommended for use on aircraft or electronics such as computers, MRI scanners, and scientific instruments.
Boeing has stated in a service letter "Dry chemical extinguishers can cause extensive corrosion damage to airplane structure, electrical systems, and electronic equipment Dry chemical fire extinguishers should only be used for airplane firefighting if there are no other extinguishers available and there is imminent danger to property or personnel. BC dry chemical agents are incompatible with strong acids , lithium metal and sodium-potassium alloy NaK , and monoammonium dihydrogen phosphate also called "ammonium phosphate", NH4H2PO4.
Mixing of fire fighting agents with incompatible materials can release toxic byproducts or pose other dangers. Alternative extinguishing agents should be used in areas where incompatible materials are likely to be used or encountered.
For example, pool chemicals should be stored separate from other hazards and water extinguishers see above or carbon dioxide units should be provided. Proper planning can avoid situations where you might have to make a choice between extinguisher types.
Ensure that the extinguishers closest to your aircraft, computers, and pool chemicals are of an approriate type if local fire codes permit and that workers in those areas are trained on when and how to use them. It takes effective training to recognize if your computer or airplane is fully engulfed in flames or a person is in danger, then possible added damage from an ABC extinguisher is moot, but using one on pool chemicals is likely to increase the peril.
CO2 carbon dioxide extinguishers are for class B and C fires. They don't work very well on class A fires because the material usually reignites. CO2 extinguishers have an advantage over dry chemical in that they leave behind no harmful residue. That makes carbon dioxide or Halotron I or FE; see below a good choice for an electrical fire involving a computer or other delicate instrument. Note that CO2 is a bad choice for a flammable metal fires such as Grignard reagents, alkyllithiums and sodium metal because CO2 reacts with these materials.
CO2 extinguishers are not approved for class D fires! To get an idea for what could happen, take a look at this General Chemistry demonstration page that includes a QuickTime movie of a magnesium metal fire contained inside a block of solid CO2! Carbon dioxide extinguishers do not have pressure gauges because carbon dioxide is a condensable gas.
Thus, pressure does not tell you how much agent remains in the cylinder. Instead, the extinguisher should have a tare empty weight stamped on it. To determine the amount of carbon dioxide remaining in the extinguisher, subtract the tare weight from the current weight. The most common extinguishing agent in this class is sodium chloride, but there are a variety of other options. You should have an approved class D unit if you are working with flammable metals.
The following types of class D extinguishing units are available through our on-line store, Safety Emporium.
Heat from the fire causes the agent to cake and form a crust that excludes air and dissipates heat. Powdered copper metal Cu metal is preferred for fires involving lithium and lithium alloys.
Developed in conjunction with the U. Navy, it is the only known lithium fire fighting agent which will cling to a vertical surface thus making it the preferred agent on three dimensional and flowing fires.
Graphite-based powders are also designed for use on lithium fires. This agent can also be effective on fires involving high-melting metals such as zirconium and titanium. Electrical fires are common in industries that deal with energy or make use of heavy electrically-powered equipment.
However, electrical fires can occur on smaller scales in all businesses i. To extinguish such fires you cut the power off and use non-conductive chemicals to extinguish the fire.
Class D The Class D fire is defined as one that uses a combustible metal as its fuel source. Examples of such combustible metals include titanium, magnesium, aluminum, and potassium. Note that there are also other metals with combustive properties you may encounter. Class D fires are a danger in laboratory environments.
However, be aware that combustible metals are used as part of production and other industry processes, and you need to be certain of what materials you are using for day-to-day operations.
When confronted with such a fire, common extinguishing agents such as water are ineffective and can be hazardous. To extinguish a Class D fire, use a dry powder agent. This absorbs the heat the fire requires to burn and smothers it as well. Class K A Class K fire is defined as a cooking fire involving combustion from liquids used in food preparation.
Technically a type of liquid fire, Class K fires are distinct enough to warrant their own classification.
Types of fire extinguisher – all you need to know, explained in our simple guide.
Cooking fires are fueled by a wide range of liquid cooking materials. The common fire extinguisher is one of the most well known and widely used safety tools. However, you cannot download the first fire extinguisher you see and expect it to keep your business safe.
Every business is different and so are the potential dangers they face. Fire extinguishers are specialized pieces of equipment that are designed to put out fires of different classes. Fire extinguisher ratings are based on the five classes of fires.
Understanding the Different Types and Uses of Fire Extinguishers
Do you have the right fire extinguishers for your unique risks? There are several different classifications of fires based primarily on the fuel source. By understanding what each fire class means, you can understand which fire types are a safety hazard at your business.
Once you are aware of what types of fires your business may encounter, you can download the proper extinguisher for protecting against them. Class A Class A fires are defined as ordinary combustibles. These types are fires use commonly flammable material as their fuel source.
Wood, fabric, paper, trash ,and plastics are common sources of Class A fires. This is essentially the common accidental fire encountered across several different industries.
Trash fires are one such example.The nozzle or other parts are not obstructed. L2 is suitable for all types of metal fires, whereas M28 cannot be used on lithium need a way to remember that? Warning: do not use on burning fat and oil fires and electrical appliances. Smothering these types of fires to remove oxygen is a common solution as are chemical reactions that produce similar effects. Also, bear in mind that water should not be allowed to come in to contact with burning metal.