A [[fire]] capsule is a device used to extinguish a [[fire]]. This device is a component of [[fire extinguishers | fire extinguishers]] portable manually and according to the type of fire, different compounds such as water, powder and gas, carbon dioxide gas and bioresal are pressed on the fire. [Http: // nfpa .com.co / en / Iranian Fire Alarm Systems Reference]
Fire extinguishers are solid metal cylinders filled with [water] or a suffocating substance such as carbon dioxide, and when you press the [lever] on top of these cylinders, the material It comes out of the capsule with a lot of pressure. In these capsules, a tube connects the pressure vessel of the capsule to the upper part of the capsule and a spring valve blocks the connection between the tube and the outlet. At the top of the [[cylinder]], there is another small cylinder that is filled with a compressed gas such as carbon dioxide, and a valve stops the release of carbon dioxide.
To use the fire extinguisher, the [[toggle]] capsule must be pulled out and its lever depressed. This lever pushes a bar to push the spring valve down and open the outlet. The compressed gas is released by pressure and is discharged from the tank to the outlet with considerable force.
It should be aimed directly at the target fuel and all over the fuel. The capsule is made in different sizes and different gases.
Types: co2 – powder and gas – halogen – water and…
Each of them has a special application.
== Features ==
=== Shutdown weight ===
The weight of manual extinguishers varies from 1 kg to 14 kg or 14 liters so that one can easily carry it. Larger types of this device are placed on wheels due to their heavy weight, and sometimes some of them are fixed in a certain place, which is no longer called a manual word, and are known as wheeled fire extinguishers.
Depending on the capacity and type of materials inside, various types of manual fire extinguishers can be used in small and different fires.
=== Types of fire extinguishing materials ===
Due to the different applications of extinguishers and on the other hand due to the different materials of combustion, extinguishing materials are also different. There are five types of extinguishers with different uses in the following extinguishers:
1- WATER FIRE EEXTINGUISHER
2- POWDER FIRE EEXTINGUISHER
3- CARBON DIOXIDE FIRE EEXTINGUISHER
4- EEXTINGUISHER FOAM FIRE floor extinguishers
5- HALOGENATED FIRE EEXTINGUISHER
=== pressure ===
In the past, sand buckets or cans containing powder were used to extinguish fires, so that there was no pressure agent to empty the material and one had to spray it on the fire by hand, but today to throw extinguishing materials from pressure agents that Inside the cylinders are used which are the following factors:
1- Inert gas pressure such as N2 into the cylinder
2- CO2 gas pressure inside the cartridge
==== How the extinguishing cylinders work ====
Extinguishers work in two ways, directly and inversely, although the inverting method is related to older extinguishers of soda acid or chemical foam.
A) “Inverted method”:
In this method, in order for the extinguishing agent to come out of the extinguisher, it must be turned upside down (upside down), otherwise the extinguishing agent will not come out and only its pressure agent will be discharged. There is a folding knob at the bottom of the cylinder to identify this type of extinguisher.
B) “Direct method”:
In this type of extinguishers, there is no need to overturn the extinguisher and the device must be used directly. Note that if we overturn the extinguisher whose function is direct, its pressure factor will come out of the NOZZLE nozzle, and if we keep the extinguisher of the inverted type direct, the same operation will be performed.
=== Throwing power ===
In order to be able to spray the extinguishing material on the fire at a suitable distance from the fire, the extinguisher must have a throwing power, which is usually at least 2 meters and at most 7 meters.
Discharge percentage: The percentage of discharge of extinguishing agents is normal under normal conditions and full charge of the device. This percentage is 95% for water, foam, carbon dioxide and halogen extinguishers and 85% for powder extinguishers.
Discharge time: This time in extinguishers varies according to the extinguishing agents and their weight or volume. The minimum discharge time is 8 seconds and the maximum is 60 seconds.
== Pressure test on extinguishers ==
To ensure sufficient pressure inside the extinguisher, the following tests are usually performed: a) Weighing: Separate the cartridge from the extinguisher and weigh it. If more than 10% of the weight of the gas contained is reduced, it must be recharged. . B) Barometer: Extinguishers that work with compressed air, the pressure inside the cylinder is shown by the barometer on it. C) Testing of solutions: Extinguishers whose pressure is supplied by the production of gas due to the chemical reaction of two substances, the production of gas is measured by combining some of the chemicals in the cylinder and calculate the amount of gas produced. .
Corrosion protection of the extinguisher cylinder body: The danger that exists in extinguishers is that the thickness of the cartridge body is weakened due to rust and corrosion of the metal from inside or outside. To prevent rust, the body of the cartridge is usually protected in the following way. A) Use of stainless metal b) Cover the inside and outside with a stainless material c) Pull the plastic cover from inside the body or on the cartridge
Body test: Extinguishers are tested during body construction to ensure their resistance to pressure. A) Mechanical leak test b) Test for minimum body thickness c) Disassembly test (d) Operation pressure test (Operating pressure is the maximum pressure that the extinguishing body normally withstands and its value is approximately Is half the pressure at which the body is tested)
== Common tests ==
All extinguishers must be tested by the consumer or manufacturer. A) Monthly visit: This visit is done once a month to three months according to the weather conditions of each region, in which case the extinguisher is in appearance and in terms of the health of the seal, being in place, the pressure does not decrease , The health of the nozzle and non-impact is checked.
B) Annual inspection: To ensure the performance of extinguishing materials inside the extinguisher on fire, some of them should be used in training and educational fires and then charge the extinguisher and prepare it for use.
C) Testing the body against pressure: According to the standard or the recommendation of the manufacturer, every few years (usually 2 years) the body of the extinguisher against pressure is tested for hydrostatic resistance.
== Types of Extinguishers ==
=== Blue Extinguishers ===
These types of fire extinguishers are of two types: Pressurized water extinguishers This group of manual fire extinguishers usually have a capacity of 9 liters or more of pure water and are used for group A fires. One of the problems with this type of extinguisher is that it can be used in areas where the temperature is less than 4 degrees Celsius (40 degrees Fahrenheit) due to freezing water. To solve this problem, manufacturers use special antifreeze solution in these areas, which can be used even at -40 degrees Celsius.
The throwing power of this type of extinguisher is 7 meters according to the British standard, but in the American standard, its throwing power is set at 10 to 12 meters. This type of extinguisher can be used intermittently. Its continuous discharge time is 60 seconds according to the British standard and 55 seconds according to the American standard. The pressure required to evacuate the compressed air inside the extinguisher is provided.
(This type of shut-off has 10 bar or 150 PSI pressure during full charge)
Because the body of this type of cylinder is under constant pressure, it must have a resistance of 40 atmospheres (PSI600). There is usually a barometer on the output cap of this type of extinguisher. This barometer is usually used for two purposes:
1) Specifies the pressure inside the cylinder. 2) Since the cylinder does not have a safety valve, if the pressure inside the extinguishing cylinder increases for any reason and exceeds the normal level, the pressure gauge will collapse and the cylinder pressure will be discharged. The outlet valve of this type of extinguisher is usually lever and to prevent it from draining, a pin with a round head is placed under the lever, which is called a toggle. In order to use these extinguishers, the toggle must first be pulled out, then, being in a suitable position in relation to the fire, the extinguisher must be taken with one hand and the nozzle with the other hand, and then the contents of the extinguisher must be poured on the fire by pressing the relevant lever.
Visit the extinguisher once a month to ensure the performance of this type of extinguisher. During the visit, observe the internal pressure of the cylinder through a barometer and make sure that the device is safe in terms of impact, the valve and the pump are safe, as well as the hose is safe. If possible, use it once a year in a training fire and recharge it. Every two years, the extinguisher body must be hydrostatically tested at a certain pressure (24 bar / 300 to 350 PSI) to ensure that it is intact.
=== Water and gas extinguishers ===
This type of extinguisher is similar to a pressurized water extinguisher, ie it contains water cylinder or antifreeze solution and it is empty. In both types of extinguishers, the inside of the cylinder is generally covered with a thin layer of plastic or stainless steel to prevent rusting. The difference between these two types of extinguishers is in the type of pressure factor. To provide the required pressure in this type of extinguisher, pressurized CO2 gas is used in a small cylinder called a cartridge. Water and gas extinguishers are generally uncontrollable, meaning that the gas stored in the cartridge is irreversible when released. The discharge rate of both types of shut-off is 95% at full charge. There is a type of extinguisher that has a shower-like nozzle that sends water out in the form of fog. The English standard sets the throwing power of this type of extinguisher at 4 meters.
To ensure the performance of this type of extinguisher, visit the extinguisher once a month by carefully opening the lid and taking the cartridge out of the cylinder, then weighing it, if more than 10% of the weight of the gas that It says on the cartridge, if it is low, it must be recharged. Then thoroughly inspect the body, cup, impact bar, needle, washer and exit.
The extinguishing cylinder should be tested every 2 to 5 years to ensure its safety.
=== Powder Extinguishers ===
[[File: Fire extinguisher powder.svg | Fingers | 150 px | View from a fire extinguisher]]
Extinguishing powder is a mixture of some chemicals used to extinguish fires. In the past, fire extinguishing powder was used to fill a number of cans or containers in various forms with powder and put them in appropriate places, and when people started a fire, they opened the lids of the cans and sprinkled the powder on the fire. Over time, powder extinguishers were designed and built to spray powder on fire.
Types of extinguishing powders: 1- Chemical powder that is used to extinguish non-metallic fires of class A, B and C. 2- Dry powder that is used to extinguish fire of Class D metals.
==== Chemical powder ====
Chemical powder itself is divided into two groups: a) Ordinary chemical powder based on sodium bicarbonate, potassium bicarbonate, potassium urea carbonate and potassium chloride and is suitable for fire extinguishing classes B and C. B) Multipurpose chemical powder that is suitable for fire extinguishing classes B and C and is based on ammonium phosphate.
==== Dry powder ====
Dry powder, which is suitable for extinguishing fires of flammable metals such as sodium, magnesium, aluminum, etc., is of several types: 1) Type S – is a combination of sodium chloride, potassium chloride and barium chloride, which after pouring on the fire a shell It creates a thick on the fire and extinguishes the fire. 2) Type C – is a combination of dried mud, graphite, sodium chloride and dried animal blood. There is another type of extinguisher based on sodium chloride plus thermoplastic.
===== Comparison of compounds used in extinguishing powder =====
Potassium compounds have been shown to have stronger quenching power than sodium compounds. For example, potassium bicarbonate is more capable of extinguishing fires than sodium bicarbonate. But the stability of potassium compounds is lower than that of sodium compounds due to their tendency to absorb moisture and also the possibility of their decomposition. For this reason, potassium bicarbonate is less commonly used in fire extinguishers due to its instability and tendency to clump. Research has shown that alkali metal salts, including potassium salts in combination with gluconic acid, can play an important role in the chemical powder formulations of fire extinguishers, either alone or in combination with small amounts of anti-clogging and anti-moisture absorbing agents, or Used in combination with other dry chemical powders such as sodium bicarbonate, ammonium phosphate and ammonium sulfate. These gluconate compounds are stable and do not absorb moisture and also have excellent extinguishing properties.
Pressure factor: In emptying powder extinguishers, there are generally two methods for discharging powder extinguishers. 1) Powder and air extinguishers 2) Powder and gas extinguishers
=== Powder and air extinguishers ===
The volume of the powder cylinder and the rest is dry air or nitrogen and at the time of charging its pressure is 10 times (150 PSI). Because the powder is constantly pressed inside the extinguisher, it is more likely to clump; Therefore, from time to time it is necessary to turn the extinguisher upside down and put it back in place. There is often a sphygmomanometer on this extinguisher that shows the pressure inside the cylinder. This extinguisher is controllable and is available in different weights from 0.5 kg to 14 kg (1 to 30 lbs). The discharge time depends on the weight of the contents, from 8 seconds to 14 seconds, and the discharge rate is at least 85% at the time of charging. The firing power of this extinguisher is 6 meters and it is used for fires of different classes.
Visit the extinguisher once a month and during this visit observe the pressure inside the cylinder from the pressure gauge and then visit the body and the seal. If possible, use a fire extinguisher once a year in a training fire.
=== Powder and gas extinguishers ===
These types of extinguishers are divided into two groups. A) Cartridge inside b) Cartridge outside
==== Cartridge inside ====
The pressure factor in this type of extinguishers is CO2 gas, which is located inside a small cylinder, which is located under the lid and inside the extinguishing cylinder. Push and push out.
==== Cartridge out ====
In this type, the CO2 gas content is located outside the cylinder and the gas outlet of the cartridge is connected to the extinguishing body, the function of which is both pulses and levers. Cartridges located outside the body have a function valve and the cartridge gas is discharged if necessary. In cartridge powder extinguishers, if gas enters the cylinder in any case and a small amount of powder is consumed, it can not be trusted for later use; Therefore, you must drain the gas inside the cylinder and then open the lid and replace the cartridge. To drain the gas from inside the cylinder, it is enough to turn the extinguisher upside down and press the lever to get all the gas out.
How to work with powder and gas extinguisher Cartridge outside: Place the extinguisher on the ground near the fire, release the toggle, then pull the rubber tube out of the clamp and hold it together with the handle without exposing your body or head or face. Install the safety shut-off valve path Open the throttle valve. (Tap on tap type). Then take the nozzle with one hand and the extinguisher with the other hand and sprinkle the powder on the fire by pressing the nozzle lever.
How to work with powder and gas extinguisher inside the cartridge: In this type, the cartridge extinguisher is placed inside the cylinder body and under the cap. When you pull out the toggle, press the lever to allow gas to enter the cylinder body from inside the cartridge, then grab the nozzle with one hand and press the lever with the other hand to spray the powder on the fire.
Periodic tests of powder and gas extinguishers: Once a month, open the cylinder lid to make sure that the powder does not clump. Make sure the cylinder outlet is also open and the rubber tube is intact. Weigh the cartridge to make sure it is charged. Recharge if more than 10% of the gas weight inside is reduced. If possible, use a fire extinguisher once a year and recharge. (Each cartridge is filled with 110 grams of CO2 gas)
=== CO2 gas extinguisher ===
[[File: Fire extinguisher CO2 b.svg | Fingers | 150 px | View from a fire extinguisher]]
From ancient times the gas has been used as a fire retardant in fixed automatic devices. CO2 gas has the following properties:
It is a non-flammable gas, odorless, neutral, non-toxic, does not cause corruption, is not a conductor of electricity, its weight is one and a half times that of air, and therefore, when extinguished, it somehow covers the surface of the fire and replaces oxygen, resulting in extinguishing action. It is done well.
The volume of the extinguishing cylinder contains CO2 gas, which is liquefied at a pressure of about 55-60 atmospheres (900-800 PSI) and is placed in the cylinder. There is empty space to expand the gas, because the extinguisher body has to withstand a lot of pressure, so it is made in one piece and without seams and welds. If it is made of steel, its total weight is increased, but if it is made of aluminum, its weight will be relatively less. Manual versions of this extinguisher are manufactured with capacities of 1 to 6 kg (12-2 lbs). In most capacities, it is designed and used in the form of wheeled or fixed automatic devices. Because CO2 gas has no effect on the consumption area, it is mostly used in closed areas and to extinguish Class B and C fires, electrical devices, computer devices, and electrical appliances in general.
These extinguishers are usually controllable, the CO2 extinguisher nozzle is in the form of a funnel or horn, and the reason is that it prevents the gas from speeding up as it exits, allowing it to expand, and also preventing loud noise. It should be noted that one pound of liquefied petroleum gas (CO2) will be produced if 8 cubic feet of gas is released. Although carbon dioxide is not toxic, when used indoors in large quantities, it reduces the amount of oxygen in the air, and anyone in the area will be deprived of oxygen as a result of suffocation.
If for any reason the internal pressure of the cylinder increases, the safety valve inside which there is a ruptured disc will operate and all the gas in the cylinder will be drained. The resistance of this disk is about 180 atmospheres (2700 PSI), so the CO2 extinguishing cylinder should not be placed in direct sunlight or in the vicinity of heating devices. The body of this type of extinguisher must be able to withstand a pressure of 450 atmospheres (7000 PSI).
To work with this type of extinguisher, first grab the handle and pull out the pin, then press the lever and pour the gas on the fire. Care should be taken that the organs do not come into contact with the discharge tube as this part may cause burns at the site of contact due to the extreme cold.
The valve mechanism of this extinguisher must be such that it opens and closes quickly, otherwise the gas turns to ice and blocks the outlet, so valves with a very small outlet are used in this device. The discharge rate of this extinguisher is 95% and its maximum throw is 2 meters. The discharge time of this extinguisher is a maximum of 20 seconds.
Periodic tests: Once every six months, make sure the device is intact, including rust, impact, nozzle and pipe damage, and valve safety. The extinguisher is then weighed and recharged if more than 10% of the gas weight inside the cylinder is reduced.
=== Halogen Extinguishers (B. C. F) ===
Although halogenated materials are acceptable and known as fire extinguishers, their use has been restricted due to damage to the ozone layer, although some fire extinguishers may still be used in some facilities. .
In order to make extinguishing materials in these extinguishers, two materials called [[methane]] CH4 and ethane C2H6 are used as basic materials, but halogenated materials replace hydrogen of these compounds and the obtained materials are not flammable and about 4 to 5 times more than The air is heavier and quickly covers the fire and prevents oxygen from reaching the fire. On the other hand, it interferes with the reactions of the fuel chains, resulting in a fire-fighting action. These materials are liquid and gaseous in the environment as long as they are inside the cylinder or closed containers.
These extinguishers can be used in most fires, especially in fires of electrical appliances as well as delicate electrical devices. This extinguisher can be used for fires that are on the same level as solids and flammable liquids.
Pressure factor: In these extinguishers, it is obtained in three ways: 1) air pressure or nitrogen 2) gas pressure inside the cartridge 3) internal pressure of the material itself
Types of halogen extinguishers 1) Type of ceiling that operates automatically. 2) The type of bolting or glass that fires by throwing on fire. 3) in a cylindrical shape
The ceiling type of these extinguishers is made in capacities of 3-9-12 kg and operates automatically. This type of extinguisher is usually installed in suitable places on the ceiling. The outlet of the liquid is closed with a small glass containing chemicals, which is connected to the outlet on one side and to the lower one on the other side, completely blocking the outlet of the liquid.
When a fire occurs in a place, the heat from the fire reaches the glass containing the chemicals, which is a kind of alcohol, and the material inside the glass expands. And covers the fire and suffocates the fire.
Glass There are chemicals in different colors, each of which breaks the glass at a certain temperature; Therefore, according to the need, the necessary type can be selected and used. Type of bowling In these devices, halogenated material is placed in bowling glass with a capacity of about 1200 grams of halogenated material. In case of fire, it is thrown into the fire, which turns into a gas due to breaking the bottle of halogenated material, and the fire is extinguished.
The cylindrical type of this type of extinguisher can be used both manually and automatically. If there is a fire in the place where the above extinguisher is mounted on the wall, if no one is there or does not notice, and also the heat reaches the bubble of the glass containing the chemical, the glass will be broken and the exit of halo liquid will be opened.
=== Foam Extinguishers ===
The floor used for firefighting is a liquid that is thrown on the flammable material to quickly cover the fire and prevent flammable gas from rising from the material and by covering the surface of the flammable material to prevent oxygen oxygen from reaching the fire. Does. Its specific gravity is less than the specific gravity of flammable liquids, so it floats on its surface and does not go down. These types of extinguishers have become obsolete in recent years due to their problems. (The throwing power of floor extinguishers is about 5 meters and the ratio of its combination with water is 1 to 8, ie 1 liter of foam is added for every 8 liters of water, and the capacity of this type of extinguishers is usually 9 liters)
== Identify the type of extinguishers ==
Here are some signs and specifications provided by the manufacturers or other methods that may be helpful in this regard:
A) Standard: The standard institute usually requires the manufacturer to write the necessary information on the body, therefore on the body of extinguishers, information such as the type of extinguishing material, capacity, uses and how to work with it is written on a label or in the form of a drawing. Draws are installed on the extinguisher.
B) Letters: It may not be possible for all users to read foreign texts, so some letters representing a group of flammable materials may be used and the extinguisher may be used to extinguish the fire.
Letter A This letter is usually written on the body of a fire extinguisher that is suitable for burning solids such as wood, paper, fabric and cardboard.
The letters A.B. These letters are usually on the body of a fire extinguisher used to burn ordinary solids such as the above and liquids such as oil and gasoline. . . It is appropriate to be written.
The letters A .B.C These letters are usually used on the extinguisher body, the powder of which is suitable for the three groups of burning solids and liquids mentioned above, in addition to electrical appliances.
B.C letters These letters are usually written on the body of the extinguisher, which is suitable for burning liquids and electrical appliances.
C) Identification from the parts of the device 1) CO2 gas extinguisher has a one-piece body, seamless and funnel-shaped nozzle. 2) The water-containing extinguisher has a nozzle with a small diameter. 3) The extinguisher containing the mechanical foam has a nozzle with vent holes. 4) Extinguishers containing powder have a normal nozzle.
D) Identify the type of extinguisher by the color of the cylinder body 1) Extinguisher containing water in red 2) Extinguisher containing powder in blue 3) Extinguisher containing CO2 in black 4) Extinguisher containing halogen in green 5) Extinguisher containing foam in color Yellow or cream color
Type of extinguisher of solids Flammable liquids Flammable gases Electrical appliances Flammable metals Water ++ – – – – Floor + + + – – – Chemical powder + + + + + – Dry powder – + + + – CO2 – + + + + – Halogenated materials – + + + –
== Determine the appropriate place to install the extinguisher ==
1) To be installed at a maximum height of 1.5 meters above the ground. If the weight of the extinguisher is more than 18 kg, it should be installed at a maximum height of 1 meter above the ground. 2) be located near inputs and outputs. 3) The access route is short and free of cumbersome and annoying equipment. 4) be installed in a place that minimizes the possibility of physical damage to it. 5) Do not place the cylinder outdoors in direct sunlight or snow and rain. 6) Care should be taken to install the extinguisher at a distance away from hazardous materials. 7) When the extinguisher is installed on the wall, special fasteners must be used. 8) Distribute evenly.
== Select the type of extinguishing capsule ==
The most important thing about fire extinguishers is to know that each fire extinguisher is suitable for extinguishing a certain type of fire; Therefore, you must first prepare a suitable extinguisher based on the type of material that may be affected by the fire. [Http://fire-training-college.nfpa.com.co/en/ Iran School of Fire Science and Technology]
== Classification and application ==
=== Target letter ===
Depending on the type of fire, the purpose of the fire in the international system (except the United States) is as follows:
{| class = wikitable
| –
! Target !! A word of expression
| – align = center
| Ordinary solids || A
| – align = center
| Liquids || B
| – align = center
| Electricity || C
| – align = center
| Reactive metals || D
| – align = center
| – Oils || K
|}
