Keeping at least one fire extinguisher in your home is not a bad idea. What many people don't know is that there are different types of fire extinguishers for different types of fires. This is critical knowledge given that some types of fire extinguishers can actually exacerbate fires they are not designed to fight. Take the CO2 extinguisher. It gets a lot of press, but do you need one for your home?
In most cases, no. CO2 fire extinguishers are most frequently recommended for offices, retail shops, schools, hospitals, etc. Their main purpose is to extinguish electrical fires. However, CO2 extinguishers are effective against Class B fires involving flammable liquids. Herein lies the confusion.
Different Fire Classes
Fires are categorised under different classes to make it easier to understand how to fight them. Note that classifications may differ from one country to the next. In the UK for example, there are six classes:
- Class A – involving ordinary combustibles like paper, wood, and textiles.
- Class B – involving flammable liquids with ignition temperatures of less than 100°C.
- Class C – involving flammable gases.
- Class D – involving solid and powdered metals.
- Electrical – involving electrical appliances, wiring, switchboards, etc.
- Class F – involving high-temperature cooking oil and fats.
The confusion surrounding CO2 fire extinguishers and residential use is based on the fact that cooking oil is a flammable liquid. Yet cooking oils and fats have a much higher combustion temperature. That makes them more difficult to extinguish. A CO2 extinguisher is likely to be ineffective against a cooking oil fire. In fact, it might even exacerbate it.
On the other hand, Class F fire extinguishers have been developed specifically to fight kitchen fires. They are wet chemical extinguishers by definition, relying on chemicals that cool the fire, extinguish it, and then seal the fuel so reignition cannot occur.
More About CO2 Fire Extinguishers
Understanding how CO2 fire extinguishers work makes clear why they are largely ineffective for residential kitchen fires. The first thing to understand is that a CO2 extinguisher expels carbon dioxide. That means it is expelling a gas rather than a wet chemical or foam.
A CO2 extinguisher deals with fire by quickly replacing oxygen with carbon dioxide. Remember that fire is fed by oxygen. Remove oxygen from the equation and the fire cannot continue burning. This is the very strategy behind using a CO2 extinguisher.
The challenge CO2 extinguishers pose in residential environments is the nature in which they work. The gas inside is highly pressurized, thereby creating a forceful blast of CO2 when the extinguisher's handle is depressed. Opening one of these extinguishers on a residential kitchen fire is problematic for two reasons. First, the CO2 is unlikely to extinguish the fire. Second, the high-pressure blast could force the fire across the room where it ignites other combustible materials.
If your only concern about a fire at home relates to the kitchen, a CO2 fire extinguisher is not a good choice. Get one specifically designed for kitchen fires. In the absence of such a fire extinguisher, you can always smother a kitchen fire with baking soda or salt.
Electrical Fires at Home
Although CO2 fire extinguishers are not appropriate for kitchen fires, you may still want one at home if you are concerned about electrical fires. For example, you might run a home-based business that requires a full range of computer equipment and office electronics. Maybe your home office is outfitted with:
- desktop computers
- a printer and fax machine
- a copy machine
- electronic devices specific to your industry.
A home office packed with electronics does pose a higher risk of fire than one with no electronics at all. Although this is no reason to live in fear of fire, you might want to keep a CO2 extinguisher in your office just to be safe. Having the capacity to quickly put out an electrical fire could mean the difference between saving your office and losing it.
CO2 Extinguishers for DIYers
Another valid reason for having a CO2 fire extinguisher at home is doing a lot of DIY work. You might be the kind of hobbyist who has a full workshop at home. You are looking at a space with table saws, band saws, lathes, and all sorts of power equipment. You might be in the same boat as the person with the home office.
The more work you do in your home workshop, the greater the chances of a small flight starting. Again, this is no reason for panic. But placing a CO2 fire extinguisher in an easily accessible location could prevent a small workshop fire from becoming a major disaster.
To summarise, most people do not need a CO2 fire extinguisher at home. CO2 fire extinguishers should never be used to combat kitchen fires sparked by cooking oil and fats. If homeowners are concerned about electrical fires or fires caused by flammable liquids (like paint thinner) a CO2 extinguisher is appropriate for such limited uses.
