Fire Extinguisher Types

A fire extinguisher is usually a vessel containing an agent that can actively control a fire. It is an emergency measure to mitigate small occurrences in a small area. They are not designed to fight fires that have gotten out of control or those that endanger the user. These items are installed in many locations as a safety precaution especially in high risk zones. The classification of fire extinguisher types will depend on the criteria used to differentiate them. Having the right information on what type to purchase or use in case of various types of fires is important can mitigate risks. You also need to ensure that any fire extinguisher service has the appropriate fire extinguisher maintenance contract in place.

Classification by Operation

There are two fire extinguisher types depending on how they are operated. This is a technical division that is not commonly used colloquially.

Stored pressure: These are commonly used units where the expellant and the agent that extinguishes the fire are stored in the same chamber. Different kinds of propellants are used for every agent to enhance the effectiveness of the extinguisher.

Cartridge-Operated: These are units that have the expellants and the agent in separate chambers. They are easy to use and require only puncturing of the expellant chamber to perform the task. Because of this, they are found in high-risk areas where small fires are commonly experienced such as industrial sites.

Classification by Type of Fire

The causes of fire vary and they cannot all be controlled using the same agent. For instance the use of water to extinguish a fire fuelled by oil will only help it in spreading. This is the most popular criteria because it is easy to understand and the information is straight-forward. There are alphabetical indicators for this type of rating and the colored shapes within which the letters are displayed can also help you distinguish them. This is the most reliable criterion in identification of the right extinguisher and should be known by everyone.

Class A: This is an indicator label for a fire that has ordinary combustible material such as paper, wood and even plastics. The indicator shape is a green triangle and a handy mnemonic to recall is Ash’. There are different agents used in these cases but primarily, monoammonium phosphate is used. They have a numerical rating that shows the amount of water within the vessel.

Class B: This is an extinguisher usually used to deal with fires resulting from flammable liquids. For easy recall, the letter is in a red square and one can think of a “Barrel”. The common liquids are kerosene, gasoline and grease among others. These fires are quite dangerous and there are two agents commonly used as agents for control. Monoammonium phosphate and sodium bicarbonate smothers the fire and extinguishes respectively. The rating that is presented is usually an approximation of the area that the extinguisher can cover.

Class C: These fires are caused by live “Current” and can therefore not be extinguished by any agent that is capable of conducting electricity. The frequency of electrical equipment catching fire is quite high and should be dealt with safely. Similar agents to the Class B are commonly used since they are not conductors. The symbol used is a blue circle and no ratings are used for this class.

Class D: This is one of the special fire extinguisher types that cannot be used for multiple purposes like in the A, B and C. The indicator symbol is a yellow pentagram and a good mnemonic to recall its use is Dynamite’. They are usually found in laboratories and are useful for combustible metals such as potassium, sodium and even titanium. Unlike the first three, Class D vessels are not red but a distinctive yellow color.

Class K: This is found primarily in Kitchen’ environments and is identified by the black hexagon symbol. Like Class D, they are not red; the vessel is usually silver or white. They deal with fires that result from cooking oils and fats especially in restaurant environments.


Recognition of these separate classes is more important than knowing exactly what is inside the canister. It is important to have at least a single fire extinguisher at home in case of emergency. When buying one, consider the likely cause of fire for the place that you will install it. When an incident occurs, it is vital to remember that using the wrong type could be potentially fatal. Consider retaining the helpful information to avoid being at risk.

How to Service Your Fire Alarm System

Fire alarm systems are actually designed to protect people, property and assets in general by notifying people of fire outbreaks within their vicinity before they actually consume things. However, you can’t tell whether your fire alarm systems is operational or not by merely looking at them. This is precisely because, just like other electronic devices, test of time often seem to compromise the system’s operation and efficiency. As such, it is quite important that you service your fire alarm system from time to time. In this article, we will be discussing in details exactly how to service fire alarm systems, including the guidelines and safety measures to be observed if you want to be fully health and safety compliance.

Standards and Guidelines to Abide by when Servicing your Fire Alarm Systems

It is really important to go through these guidelines in order to avoid being in conflict with the manufacturer especially if the warranty is still valid. In addition, knowing these guidelines will save you from inconveniences that many people experience with their insurance companies.

To start with, note that most of the fire alarm system makers recommend for at least a annual test and inspection immediately after installation and acceptance. Of course there are guidelines that are set by the local authorities that are also to be adhered to.

Therefore, regardless of where you are based, be sure to comply with all the laws as required by all concerned parties.

Where to start the servicing

It will greatly help for you to find out the exact system’s age and history. This will possibly help you to determine the next step that you must take. Usually, systems under 5 years old require little effort to maintain. This is primarily because they are still new and haven’t actually been in operation for that long. Most problems associated with new fire alarm systems are always as a result of marginal installation such as improper grounding or other environmental factors such as voltage transients. With periodic testing and inspection, these minor problems can be done away with so easily.

Systems between five to ten years may have a few issues that may need somewhat specialized attention. In addition to environmental factors, systems this old may experience breakdown associated with rather harsh but somewhat normal environment. In addition, they may be facing breakdown caused by temperature, humidity and voltage fluctuations.

For systems that are between ten and fifteen years old, close attention is actually needed given that many components are likely to be malfunctioning. However, note that with frequent servicing, these systems still have the ability to operate effectively and efficiently.

Finally, systems that are approaching 20 years and over may be beyond their industrial life expectancy but still if maintained properly can work accordingly. However, they require true experts, professionals with knowledge in old fire system alarms.

Steps to Follow

Generally, fire system maintenance and servicing activities can be done in five simple steps which are:

1. Testing and calibrating alarm sensors; flame and smoke detectors, according to the manufacturer’s specifications. To do this, you will actually need some background knowledge in different sensors’ functionality. Including their testing requirements, re-installation requirements and failure modes.

2. Simulate inputs and test all the attenuators. Note that you will need specific knowledge of the system being tested.

3. Set Sensitivity – you will need understanding of any particular system, their specific application and precise fire detection theory.

4. Coordinate with the fire department within your location to test your input with their system.

5. Finally, check the battery in case of any possible corrosion and/or expiration date so that you take appropriate action, if required to take one by the situation at hand.

The steps discussed in this article are sufficient enough to provide you with some background knowledge in fire alarm systems operation and technicality. Categorically note that the knowledge is quite relevant given that you are required to pay a lot of attention to every detail since this is basically a matter of life and death. Once you are done with servicing your home fire alarm system, thoroughly inspect to ensure that nothing is out of place or broken for that matter.


Fire alarm maintenance and fire alarm service is actually not a onetime thing. It is something that is recurring and one that needs to be repeated from time to time. In addition, on a very serious note, knowledge and sometimes certification in fire alarm system maintenance may be required for you to actually perform servicing on any fire alarm system. To be on a safer side, make sure that you are in compliance with all laws governing fire within your region; also revisit your insurance policy before attempting anything to the fire alarm system.

Why Should I have my Fire Extinguishers Serviced

There is no doubt that fires are one of the most dangerous threats in any environment. For a fire to erupt only three things are needed: fuel, heat source and oxygen. Fuel represents any flammable material, a heat source enables that material to become combustible and finally oxygen allows the combustion to take place. In everyday life, a huge number of items are flammable, while many of those are highly flammable, meaning that they can catch fire and spread it quickly.

The same is true for heat sources which include heating apparatus like stoves and heaters, but also things like cigarettes, candles and other everyday things that can start a fire. Here are things that do not produce heat by design, like for example, a faulty power extension cord. But, the same item can still produce a very serious source of sparks and heat which will then spread a flame further. When these three factors combine, extremely serious danger presents itself in any surroundings, both in private and professional lives.

Because of these facts, fires are a calamity that is ever-present in everyday life. Many try to find adequate protection through smoke alarms. Although these are effective at alarming residents of a space about a threat, they are not equipped to combat an open flame in any way. That is the reason why everyone should have access to fire extinguishers, which are proven to have the capability to subdue even serious fire outbursts if they are used correctly. But, for this to be possible, the same fire extinguishers need to be serviced correctly. Here are the reasons why fire extinguishers service is a crucial element for any emergency occasion involving a fire.

In every scenario that involves a fire, the first reaction should always be the safe and expedient evacuation of all residents and occupants of a building or a home. But, when this is achieved, those who have adequate training with fire extinguishers should proceed to, without risking their life of wellbeing, try to slow down or completely extinguished a fire. For this to be successful, the fire extinguishers service needs to be properly addressed beforehand.

A service of a fire extinguisher includes a detail checkup and inspection. In this process, certified technicians inspect the device and determine that it has everything need to function properly. A modern fire extinguisher, also called dry chemical extinguisher actually present a tanks filled with an extinguishing material which can be either a dry powder or a form of foam. In the tanks is also present a compressed gas (usually nitrogen) which is activated when an extinguisher is needed. The gas expands in the tank and puts it under pressure, mixing with the main extinguishing material. When the user activates the tank, it shoots out the mixture from a nozzle. It comes out in an expanding stream because of the pressure, and its content is used to smother the fire out, denying it the crucial element of oxygen for continuing to burn.

Because of this design, it is necessary to check the state of the compressed gas in a fire extinguisher. A fire extinguishers service, which is mandatory and regulated by law, makes sure that any depleted gas capsules are replaced. In other case, if the capsule is lacking the gas, the activation of an extinguisher will not lead to rapid pressure buildup in the tank, which will not allow the extinguishing material to be used effectively. In the worst cases scenario, the gas will produce such low pressure level that the extinguisher will not work at all. Because of this, the process of recharging is very important for a solid fire protection that includes fire extinguishers.

Additional tasks which are included in a fire extinguishers service cover the inspection of the outer casing. This part of the fire extinguisher is also important because the entire tank is under pressure, meaning it is a pressurized vessel. Because of this, if it is damaged, corroded or inadequately sealed, it needs to be replaced immediately, or it might cause an explosion that can produce serious injuries. Fire extinguishers service also includes valve and cylinder assembly and installation that produce a higher level of resistance to both corrosion and rough use.

All this clearly shows that it is very useful to regularly check any fire extinguishers. Simply put an investment in fire extinguisher maintenance service today might mean saved lives and property tomorrow and ensure that you are fully fire safety compliance.