| So what's the best option for tackling electrical based | | | | maximum level of fire fighting capacity. |
| fires? Well the trusty old CO2 fire extinguisher is the | | | | Now let's get down to the technical side of how a |
| only model that is recommended for a fire that | | | | CO2 fire extinguisher actually works. Within the body |
| involves electrical equipment. This is due to the fact | | | | of the extinguisher there is carbon dioxide (CO2) gas |
| the carbon dioxide gas is non-conductive and that | | | | stored under pressure which results in it turning into a |
| once it has been discharged does not produce or | | | | liquid. As you operate the extinguisher the gas is |
| leave any kind of residue as would happen if a | | | | released under pressure into the horn which as it |
| powder or foam model was deployed. Another great | | | | diffuses and expands turns back into a gas form. |
| use of the CO2 extinguisher is on Class B fires that | | | | This action cools the surrounding air extremely quickly |
| involve flammable liquids, making this quite a versatile | | | | which is why you should not hold the actual horn as |
| product. | | | | you could receive a freeze burn. Some models have |
| It is very easy to recognise a CO2 extinguisher as | | | | frost free horns attached but if in doubt still do not |
| they are colour coded red with a black panel for fast | | | | hold the horn. |
| identification in the event of a fire related emergency. | | | | It is best to stand around 3 feet from the fire and |
| On the smaller 1kg and 2kg models they have a horn | | | | no more than 8 feet for the CO2 gas to be most |
| instead of a hose, with the larger 5kg extinguishers | | | | effective. Any close and you could easily cause the |
| having a hose with a horn attached at the end. | | | | burning materials to be blown around as the pressure |
| You can buy much larger CO2 models in the 9kg to | | | | is very high when the CO2 is released. |
| 45kg size range for use on industrial premises or at | | | | The gas disperses the oxygen from the fire and thus |
| places such as airfields or large computer server | | | | starves the fire and so causes it to go out. This is |
| rooms. Due to the extreme weight these products | | | | how all extinguishers work generally. They remove |
| tend to come on wheeled bases for easy | | | | one of the fire elements and as such the fire cannot |
| manoeuvring. | | | | burn. |
| So what can't a CO2 extinguisher be used on? Well | | | | The majority of CO2 extinguishers have aluminum |
| any fire involving Class D materials such as flammable | | | | bodies to keep the weight down as the body needs |
| metals ARE A NO GO FOR TWO MAIN REASONS. | | | | to be strong and thick because of the high pressure |
| Firstly The CO2 comes out under high pressure and | | | | gas inside. Some marine models have steel bodies as |
| can blow the metals around causing a fire to spread | | | | do a lot of foreign imports into the UK. |
| and secondly, the CO2 gas reacts with several | | | | You may notice that unlike other extinguishers there |
| volatile metals as does the extinguishing agents with | | | | is not a pressure gauge on the body. This is because |
| a few of the other types of fire extinguishers. They | | | | the gas is condensed inside the cylinder and so the |
| are also not suitable for use on Class A fires involving | | | | only way to see if it has leaked or is empty is by |
| materials such as paper, wood or cloth as again the | | | | weighing it. The gross weight should be stamped on |
| high pressure jet can spread the burning material | | | | the body of the fire extinguisher so to check if it is |
| around and so spread the fire instead of containing | | | | full simply remove the swivel horn and weigh the |
| and extinguishing it. | | | | cylinder body. Now compare the two weights and if |
| The big advantage of this type of extinguisher is the | | | | they match it is full. If not then it is empty or has |
| fact it is perfectly safe to use on electrical equipment | | | | been used. |
| and will not damage the items or leave any harmful | | | | It can be expensive to refill a CO2 extinguisher and |
| residue after. If you go to any office or work place | | | | have a company come out to inspect it so more |
| where sensitive electrical equipment such as | | | | often than not it is much cheaper to just buy a new |
| computers are present you will virtually always see a | | | | one and have your local authority at sites such as |
| CO2 model. They are often combined with foam, | | | | waste dumps recycle the old one. Do not just throw |
| water or water additive extinguishers to offer the | | | | them away as this is bad for the environment. |