fire extinguisher

[John K Jordan]

Just a quick note about CO2. Don't use it on a wood stove. The thermal shock is likely to seriously crack a cast iron stove and allow any remaining fire to spread.

CO2 is apparently good for destroring murder hornets colonies. Don’t try this yourself.

[Lon Crosby]

First, the prerequisite for effective use of a fire extinguisher is 1) training and 2) experience. In the old days (anyway), all hospital personnel had to be recertified annually in the use of fire extinguishes. Everyone did a biomass fire and a petroleum fire. No exceptions and no exemptions. So light some contained fires and put them out, and then let your significant other, kids and grandkids do the same.

Second, there are better solutions for many situations beyond CO2 and water. Adding an emulsifier/detergent to a water based extinguisher fundamentally improves the extinguisher's ability to put out fires and your lack of experience. There are several solutions available approved by the Forest Service such as ColdFire. Freeze protection for water based extinguishers can either be a salt solution or propylene glycol. One freeze protected formula for a 2.5 gallon pressurized "water" extinguisher is 1 gallon plus 1 quart of distilled water, 1 gallon of low freeze point RV antifreeze (essentially full strength propylene glycol) and 1 quart of ColdFire. This mixture will work on field fires, engine fires (oil, diesel, ethanol, etc.), hot bearings - and it is non-toxic. Used to put out fires in alcohol fueled race cars including spraying it directly on people. The only question is safety around 120/240 volt electrical. So look at the data and watch the videos.

[Brice Rogers]

The smaller extinguishers, like the 2.5# 1A:10B:C (nine second dishcharge), the 5# 3A:40B:C (14 second discharge time), are of limited use in anything but a small fire on the stove or the like. Go big and don't have confidence in the small ones. Also, on a dry chemical extinguisher, once you pull the pin and spray, it has to either be discarded or refilled. The dry chemical in valve will cause it to lose the propellent over time.

A 10 # C02 extinguisher has a 9 second discharge time, and the 15# has a 15 second discharge time. Perhaps long enough if you know what you're doing, but not much good if you don't know what you're doing. Once you start, you keep spraying until it is empty.

Going big is best. In my shop I keep a 2.5 gallon water-type extinguisher (they put in anti-freeze in cold climates). It isn't the biggest but it has a 50 second discharge time and sprays 25 or 30 feet. It is good for amateurs (like me). You can pick them up on ebay for under $50. I've got a half dozen around my house.

I'm not trying to debate the different types of extinguishers. But bigger is definitely better.

BTW, I went to an all-day fire school. I used a few dry-chemical, a whole bunch of 20# C02 extinguishers, water extinguishers and was lead man on a three person high pressure water hose going into a burning (metal -- ha ha) building with full gear. It actually was a fun course. I came home with soot on my face and a smile.

Putting out a highly flammable liquid floating on a 10 x 10' tray filled with water was good practice with the C02 extinguisher. We had just enough C02 as to put it out ONCE. But if we stopped for a second to check progress, the whole thing re-flamed and we didn't have enough C02 left. My own advice is that if someone uses an extinguisher that they aim it at the base of the flames, swing it from side to side and keep spraying until there is nothing left.

A voice or "mantra" that came to me as I was fighting an out-of-control brush fire by myself (it was a really scary situation but it was like someone talking in my ear) was: if you have fought the fire for 20 seconds and are not making much of a difference, you've got to change your method of attack. What you're doing isn't working. In my case, I had to change my method of attack and THEN I made a difference.

Just my own opinions....

[Jon Endres]

I teach fire safety at my workplace and was a volunteer FF for 10 years, but the best piece of advice (maybe more of an anecdote) regarding fire extinguishers came from someone outside the fire service. I was told to go look at the fire extinguishers hanging on the walls in the big box stores (HD, Lowes) and compare them to the ones on the shelf for sale. Almost always, the ones they have on hand for firefighting are quality brands like Amerex, Badger or Buckeye. These are heavy, all-metal, rechargeable units that are tested and certified at least annually. The ones on the shelf are usually el-cheapo plastic units, or metal with plastic valves and parts, and they're OK for a single use if they actually work. I purchased Amerex extinguishers, 5# ABC for the house and 10# ABC for the garage, and I'm trying to get my hands on a large water extinguisher for the shop (they occasionally show up used) because I can refill it myself. What's your peace of mind worth? $100 for a high-quality extinguisher is cheap insurance.

[Aaron Woods]

This year marks 29 years in the fire service so I know a little about fire extinguishers.

With the time change I changed each smoke alarm battery and got me thinking about fire extinguishers.

-Noticed home owners models that are refillable. Is this something worth looking into or is it not cost effective?
-Is it worth my time to check with a local fire extinguisher co or just buy from the big box stores?
-Want at least one for the house and each garage. Anyone put one in their car/suv and maybe a Zero Turn mower?
-Any other tips I should know?
-Why is the white Kitchen fire extinguisher only B and C and the Red fire extinguisher is A and B and C and is a little cheaper?

First of all, good job taking care of your smoke detectors. Yes they do give false alarms, but they are effective and have saved many lives.

There is a significant cost difference between refillable and non-refillable. Is the cost worth it in a home is debatable.
The refillable are better built and more durable, which could be important in a high traffic area and why this is usually what you see in a commercial setting where the public may bump or otherwise fiddle with extinguishers. Other advantages are they can be refilled, and repaired so if some knucklehead discharges it, knocks it off the wall and breaks off the gauge or handle, steals the hose etc it is cost effective to the company because the service that maintains their extinguishers can probably put it back into service for less than the price of a new disposable.
In a home this is usually not an issue, but better built is always nice piece of mind. Technically fire extinguishers have to be hydrotested (or replaced if disposable) every 6-12 years (varies by type), but many homeowners don't bother. Personally I have a mix, I have a couple of refillable 10lb ABC extinguishers placed at strategic locations (2nd floor top of the stairs, kitchen door and by the shop door) and a couple of smaller disposables which being smaller are easier to have more easily accessible. I also keep an ABC and a 2-1/2 gallon pressurized water extinguisher, and the garden hose handy when I'm welding. Since a fire when welding is most likely grass or wood the garden hose will be most effective, but the water can gives me some mobility in case something weird happens (flaming squirrel?).

You can probably buy 2-3 disposables for the price of one refillable at the 2.5 to 5lb size, these are the most common home sizes. At the 10lb and larger size you are looking at much less savings, I don't know maybe 20-30% vs buying a refillable model, still if you buy 3 extinguishers that could be a difference of $60-100. The "weight" class is weight of the agent, not the whole extinguisher. A 5lb ABC probably weighs in at 8-9lbs.
Weight is another consideration, a bigger extinguisher can put out more fire but it weighs more, this is why most people go with 2-1/2 to 5lb extinguishers in the home. Not everybody can handle a fire extinguisher weighing 15-30lbs+ effectively, think about who might need it, children, small adults, elderly or disabled people. Key locations in the house should be hazard areas, garage, kitchen, and depending on layout consider one where it is accessible to the bedrooms. Despite the name the true intent of a fire extinguisher is to maintain an exit path, not extinguish a fire. A fire on the stove, or trash can yes, half of your garage on fire, no. An extinguisher on a vehicle is worth having, it can easily be the difference between a few hundred dollars damage from a fire under the hood to total loss of the vehicle and contents. One of my more memorable car fires was caused by a squirrel storing acorns under the exhaust manifold. The burning acorns burned through the fuel lines, the passenger compartment was well involved by the time we arrived, a fire extinguisher might have made all the difference. We did at least save the groceries in the trunk so not a total loss.

There is a Class K extinguisher which is actually a foam solution specifically designed for oil and grease fires which are common in kitchens (K for kitchen) but often marked as BC in the home. These extinguishers are often white, but not sure if they have to be. In commercial settings they are usually chrome, like pressurized water extinguishers. Dry chemical extinguishers are extremely messy when discharged, so another benefit of the K extinguishers is the mess is more localized. Beyond that Dry chem BC extinguishers may be cheaper or more effective depending on which specific chemical formulation (the most basic BC agent is essentially just highly refined baking soda) on flammable liquids for a similar amount of agent compared to ABC. ABC being a better all around extinguisher, but if the code just says BC is required that could be a cost savings, or at say something like fueling area the BC extinguisher might be more effective for the size.

I've heard that for the smaller "home" style extinguisher, that they should be shaken every once in a while to keep the stuff inside from settling into a lump. Any truth to that?

Thanks.

This is actually true, and not just in the home. It is common practice during a building inspection to shake the extinguisher, turn it over and give it a couple whacks with the heal of a hand. The powder can settle over time and become a big clump. Don't go whaling on it with a hammer but checking the gauge and giving it a shake every month is not a bad habit. During fire extinguisher training it is common to get old extinguishers to use. I have seen quite a few where all that came out was dusty air because the agent was all clumped at the bottom. To be fair I bet a lot of those extinguishers spent every bit of 12 years hanging on a wall without any attention. This is particularly an issue in vehicles as years of road vibration can help pack it all down.

Is there a reason I WOULD NOT want an ABC extinguisher in the Kitchen vs the Kitchen extinguisher that is only BC?

As I mentioned above dry chemical (which includes all ABC extinguishers) is very messy when discharged. It is a very fine powder that gets everywhere. Years ago a local police station accidently discharged a fire extinguisher and unfortunately it went straight into the HVAC system and then throughout the whole building. It cost more than $10,000 to get the building cleaned.

First, the prerequisite for effective use of a fire extinguisher is 1) training and 2) experience. In the old days (anyway), all hospital personnel had to be recertified annually in the use of fire extinguishes. Everyone did a biomass fire and a petroleum fire. No exceptions and no exemptions. So light some contained fires and put them out, and then let your significant other, kids and grandkids do the same.

Second, there are better solutions for many situations beyond CO2 and water. Adding an emulsifier/detergent to a water based extinguisher fundamentally improves the extinguisher's ability to put out fires and your lack of experience. There are several solutions available approved by the Forest Service such as ColdFire. Freeze protection for water based extinguishers can either be a salt solution or propylene glycol. One freeze protected formula for a 2.5 gallon pressurized "water" extinguisher is 1 gallon plus 1 quart of distilled water, 1 gallon of low freeze point RV antifreeze (essentially full strength propylene glycol) and 1 quart of ColdFire. This mixture will work on field fires, engine fires (oil, diesel, ethanol, etc.), hot bearings - and it is non-toxic. Used to put out fires in alcohol fueled race cars including spraying it directly on people. The only question is safety around 120/240 volt electrical. So look at the data and watch the videos.

Class A foam is effective at making water "wetter" and is essentially highly concentrated dish soap. It breaks the surface tension of water allowing it to better soak in to wood, paper, grasses etc. "Wet water" was an early brand name and dish soap has been used as the budget version for decades. Some of these other additives like Coldfire do work, but they are often snake oil as far as the claims. It is rare to see a fire department use them, too expensive for too little improvement. Class A foam on the other hand has become wide spread particularly where wildfires are common.

I teach fire safety at my workplace and was a volunteer FF for 10 years, but the best piece of advice (maybe more of an anecdote) regarding fire extinguishers came from someone outside the fire service. I was told to go look at the fire extinguishers hanging on the walls in the big box stores (HD, Lowes) and compare them to the ones on the shelf for sale. Almost always, the ones they have on hand for firefighting are quality brands like Amerex, Badger or Buckeye. These are heavy, all-metal, rechargeable units that are tested and certified at least annually. The ones on the shelf are usually el-cheapo plastic units, or metal with plastic valves and parts, and they're OK for a single use if they actually work. I purchased Amerex extinguishers, 5# ABC for the house and 10# ABC for the garage, and I'm trying to get my hands on a large water extinguisher for the shop (they occasionally show up used) because I can refill it myself. What's your peace of mind worth? $100 for a high-quality extinguisher is cheap insurance.

If they are not subject to abuse the cheepos are fine. If you can afford better I'm not going to dissuade you from buying them, I have done so myself. However if somebody can buy one good one and hope it is where they need vs buying 2 or 3 to keep around the house or to replace one after their kids discharge one great. Hopefully a fire extinguisher will never be needed at all, so once should be enough.

The water cans are great where your main hazard is ordinary combustibles (wood, cloth, paper etc), I'm sorry to see them fall out of use as they were relatively cheap, easily refilled, work well and also make great squirt guns. I have one I keep handy when I'm welding (I have to weld outside), great piece of mind in case a hot spark finds some dry grass, stray saw dust, wood scraps etc. I always try to make sure the area is clear, but those sparks can get pretty frisky.


Training is huge, so much better if you have used a fire extinguisher before you need it for real. A lot of fire extinguisher companies put on this kind of training so worth asking around the local area.