Portable Extinguishers onboard Ship
Usually, there are four types of portable fire extinguishers onboard are commonly seen. Such as soda acid extinguisher, Foam, Dry powder and carbon dioxide extinguisher.
Portable Soda acid Fire Extinguishers Onboard
It is one of the portable fire extinguishers onboard ship. The soda acid has sodium bicarbonate solution in its container. Also, there is a plunger arrangement on the screw on the cap of the extinguisher. And it is covered with a safety guard. Also, we can see the sulphuric acid in a glass container. This glass cylinder will breakdown when the plunger is stuck in it. And then the sodium bicarbonate and the acid will mix together.
And this reaction will cause the production of carbon dioxide gas. Also, this gas will exert pressure on the liquid above it and push it out. Also, it will come out through the nozzle. We can fix this extinguisher in the accommodation space. And the soda acid extinguisher commonly used to put off the class A fire.
Portable Chemical Foam Fire Extinguishers Onboard:
It is one of the portable fire extinguishers onboard ship. The foam extinguisher has sodium bicarbonate solution in its container. Also, there will be aluminium sulphate is filled in a polythene container inside. This container is covered with a cap with a plunger. We can release the cap and unlock the foam extinguisher by turning the plunger. At that time, both the liquid will mix together. Because of this reaction, the carbon dioxide will form. Also, this will exert pressure and push out the foam.
Mechanical Foam Extinguisher:
It is one of the portable fire extinguishers onboard ship. This mechanical foam extinguisher has water filled in its container. Also, as we said earlier, there will be a cylinder inside. That cylinder is filled with carbon dioxide and a solution of foam. The main container will occupy with a plunger arrangement. And also a safety guard is present. At this time we press the plunger, then the carbon dioxide gas will release. And the foam and water will mix together.
The nozzle in it is a special kind of nozzle. When the mixture of the water and foam goes through the nozzle, then the special nozzle will produce the foam. The foam extinguishers will be in the area which has high possibilities of fire. The foam extinguishers will usually use to put off the class B fire.
Related Article: Fire Fighting Procedures Onboard Ship.
Carbon dioxide Extinguisher:
In the carbon dioxide extinguisher, we use the high pressure to the carbon dioxide gas to store it in a liquid state. There will be a tube at the centre line and this will help to discharge the carbon dioxide. We can release the carbon dioxide out by means of two way. One id by bursting the disc by the plunger or by triggering the valve while we discharging the carbon dioxide. Then the liquid will convert automatically when the pressure will reduce
After the conversion, the gas will go through the hose followed by a discharge horn. The carbon dioxide extinguisher will use to put off the class B and class C fire. Also, carbon dioxide extinguishers will be in machinery spaces. Also, it will use to put off the fire caused by electric equipment. And we should not use in the accommodation space.
Dry Powder Extinguisher:
The dry powder extinguisher will fill with a bicarbonate powder in its container. There is a cylinder with carbon dioxide filled is fitted below the plunger arrangement at the centre line. When we push the plunger, then the carbon dioxide will exert pressure on the powder.
And this causes the powder to get out through the nozzle. We can use the dry powder extinguisher to put off the fire in all the classes. And another thing is it will not cool the area since it has no cooling effect. The location of the dry powder extinguisher will be near the electrical equipment.
Maintenance of the Portable Extinguishers:
As we know the portable extinguishers are building with very high pressure. So we should check it regularly. In the case of the foam extinguisher and soda acid extinguisher, it should test for the first time to 25 bar. And after that with an interval of four years, it should check with 20 bar pressure. About the carbon dioxide extinguisher, it should test to 207 bar for the first time. And then interval of ten years 2 times after that 5-year interval. And the dry powder extinguisher should text to 35 bar with an interval of 4 years
Also, all the extinguishers should test based on their discharge mechanisms. Such as soda acid and dry powder extinguisher should test with 20% of discharge every year. And in case of the foam extinguisher, it should check with 50% discharge every year. Also, check regularly for leakage. The carbon dioxide extinguishers must check regularly for detection of any leakage.
The plunger of the extinguisher should check regularly for the free movement. Also, make the vent holes very clean and put grease in the caps. Keep the extinguisher in a good and clean manner. It’s all about safety.
Conclusion: Hereby we discussed the working, construction and the functions of each portable fire extinguishers. comment on your opinions as well as queries below.
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