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How to pick the right fire extinguisher for your farm shop

There is more than one type of fire extinguisher. 
Find out which type is best to keep your farm shop safe

fire extinguisher

In any typical farm workshop there are always flammable materials inside, such as liquids like oil and gasoline or greasy rags and ordinary wood and paper. In the same space is a variety of potential ignition sources, a welder or grinder that can throw sparks, the electrical systems of vehicles or machines stored inside, even gas-flame torches.

The risk of fire is very real, and more than a few farm shops have burned to the ground. The best way to ensure yours doesn’t go up in smoke is to start by having a fire extinguisher on hand. But there is more than one type and not all work on every type of fire. Here’s a look at your extinguisher options.

First of all, fires are classified by the type of material burning. Class A fires are fuelled by ordinary materials, like paper, wood or some plastics. Class B fires involve combustible fluids like gasoline and oils. And Class C fires are electrical.

There is also a Class D fire, which describes burning metals, like magnesium. But it’s unlikely the average farm shop will ever experience one of those.

Class A, B and C fires, however, are high on the probability list. So every workshop should have extinguishers that can cope with all three. An ordinary dry chemical extinguisher will handle that job, just look for an ABC rating, which will be displayed on its body.

Dry chemical extinguishers smother a fire with a powdery, non-toxic agent that can leave you with a big mess to clean up afterward. But at least you’ll still have a shop that needs cleaning. And if you spray dry chemical into the engine bay of a vehicle to suppress a fire, you may find you have to remove and clean the carb (if it’s an older machine) along with other components to try and get rid of residual chemical.

fire extinguisher
x photo: Scott Garvey

An alternative to the dry chemical type is a carbon dioxide (Co2) extinguisher. The Co2 displaces oxygen in a small area, putting the fire out that way. A benefit to this type is it does not leave a big residue mess, making it ideal for engine bay flare ups. A disadvantage is it is not rated for Class A fires. The high-pressure gas cloud it creates can scatter burning material, actually spreading a Class A fire.

If you need to extinguish your own burning clothes or a coworker’s, the dry chemical extinguisher is better suited for that. Co2 will work, but it can also cause frostbite to skin, adding to injuries. And because it displaces oxygen it can cause suffocation if you surround yourself with it. You really don’t want to pass out in the middle of fighting a blaze.

There are also still Halon extinguishers on the market, which use Halon 1301 or Halon 1211 gas. These gasses have been identified as long-lasting ozone depleting agents, but manufacturers are allowed to use existing stocks in new extinguishers. They work in a manner similar to C02, stopping the chemical reaction involved in a fire.

It’s best to avoid buying cheaper, small, plastic-bodied extinguishers, opt instead for a five or 10 pound steel-bodied, rechargeable types. These good-quality extinguishers also have a pressure gauge that will clearly indicate if they are still serviceable.

Where to put them

Mounting ABC extinguishers at eye level near exits is a good idea. That way in the event of a fire your escape route and path to an extinguisher location are the same, so making a fight or flight choice won’t involve going away from an exit — and safety — to find an extinguisher. If the fire is of a size that you can tackle it with an extinguisher, you’ll still have your escape route at your back if things get out of hand.

If you have a designated repair area in your shop where you could experience a Class B or C fire, placing a Co2 extinguisher near there will provide quick access to deal with small flare ups without leaving that dry chemical mess I mentioned earlier. You’ll still need ABC extinguishers near the exits to fall back on, though.

But it’s important to remember this: if the fire is large and flames are already lapping at the ceiling or the building is rapidly filling with smoke, getting out is probably your only sensible alternative.

After successfully suppressing a workshop fire, keep a close eye on things for quite a while in case of a flare up. And if you can safely move the problem material outside, do it. If fire flares up again, at least your shop won’t be at risk.

And when using an extinguisher, discharge the contents fully to ensure a blaze is out. Once activated, an extinguisher won’t hold pressure over the long term any more, anyway. It will need to go to a service facility to be refilled.

According to Leonard Sharman, senior media advisor for Cooperators Insurance, having extinguishers in your shop won’t guarantee you an insurance discount. But, he suggests, demonstrating you’re prepared for fire in your shop may result in an underwriter offering you a discounted premium. “It is a factor that the underwriter takes into account when reviewing the policy,” he said in an email.

About the author


Scott Garvey

Scott Garvey is a freelance writer and video producer. He is also the former machinery editor at Grainews.



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